Focus

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Geomatica® Focus User Guide Version 10.1

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Geomatica® FocusUser Guide

Version 10.1

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© 2007 PCI Geomatics Enterprises Inc.®. All rights reserved.

COPYRIGHT NOTICESoftware copyrighted © by PCI Geomatics, 50 West Wilmot St., Suite 200, Richmond Hill,ON CANADA L4B 1M5 Telephone number: (905) 764-0614

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Canadian GovernmentUse, duplication, or disclosure by the Government is subject to restrictions as set forth inDSS 9400-18 "General Conditions - Short Form - Licensed Software".

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PCI, PCI Geomatics, PCI and design (logo), Geomatica, Committed to GeoIntelligenceSolutions, GeoGateway, FLY!, OrthoEngine, RADARSOFT, EASI/PACE, ImageWorks,GCPWorks, PCI Author, PCI Visual Modeler, and SPANS are registered trademarks of PCIGeomatics Enterprises, Inc.

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All other trademarks and registered trademarks are the property of their respective owners.

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Table of ContentsUsing the Focus online help ................................................................................................................................................................ 23

Using technical references ........................................................................................................................................................... 23Using the GDB formats reference ................................................................................................................................................ 23

Working with Focus .............................................................................................................................................................................. 25Opening a file ................................................................................................................................................................................. 25Adding data to a project ................................................................................................................................................................ 26Using the Add Layer wizard .......................................................................................................................................................... 26Understanding the Focus control pane ....................................................................................................................................... 27Using the Maps and Files trees .................................................................................................................................................... 28

Changing the layer priority........................................................................................................................................................ 28Viewing layer properties............................................................................................................................................................ 28Viewing auxiliary data............................................................................................................................................................... 28Adding image channels............................................................................................................................................................. 29

Combining layers ...........................................................................................................................................................................30About the Combined Layer dialog box...................................................................................................................................... 30About the Select Layer dialog box............................................................................................................................................ 31

Working with project files ............................................................................................................................................................. 31Saving a project........................................................................................................................................................................ 31

Using the Layer Manager .............................................................................................................................................................. 31Changing layer properties......................................................................................................................................................... 32Using the Zoom Scale Active feature........................................................................................................................................ 33

About rotated rasters .....................................................................................................................................................................34Managing data properties ............................................................................................................................................................. 35About the Map Properties dialog box .......................................................................................................................................... 35

General tab............................................................................................................................................................................... 35Page Setup tab......................................................................................................................................................................... 36Default RST tab........................................................................................................................................................................ 37

About the Area Properties dialog box ..........................................................................................................................................37General tab ..................................................................................................................................................................................... 37Layout tab .......................................................................................................................................................................................38Projection/Extents tab ................................................................................................................................................................... 38Using a math model with images ................................................................................................................................................. 40Using the math model for georeferencing ...................................................................................................................................41

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About the Math Model Area Properties dialog box .....................................................................................................................42General tab............................................................................................................................................................................... 42Layout tab................................................................................................................................................................................. 42Projection/Extents tab............................................................................................................................................................... 43

About the RGB Layer Properties dialog box ............................................................................................................................... 44General tab............................................................................................................................................................................... 44Source Images tab.................................................................................................................................................................... 45Source LUTs tab....................................................................................................................................................................... 46Display tab................................................................................................................................................................................ 46

Display within Zoom Scale tab ..................................................................................................................................................... 47About the Grayscale Layer Properties dialog box..................................................................................................................... 47General tab............................................................................................................................................................................... 48Source Images tab.................................................................................................................................................................... 48Source LUTs tab....................................................................................................................................................................... 48Display tab................................................................................................................................................................................ 49Display within Zoom Scale tab.................................................................................................................................................. 49Labels tab................................................................................................................................................................................. 50

About the PCT Layer Properties dialog box ................................................................................................................................50General tab............................................................................................................................................................................... 50Source Image tab...................................................................................................................................................................... 50Display tab................................................................................................................................................................................ 51Display within Zoom Scale tab.................................................................................................................................................. 51Labels tab................................................................................................................................................................................. 51

About the Bitmap Layer Properties dialog box ...........................................................................................................................52General tab............................................................................................................................................................................... 52Source Images tab.................................................................................................................................................................... 52Display tab................................................................................................................................................................................ 53Display within Zoom Scale tab.................................................................................................................................................. 53

About the Vector Layer Properties dialog box ............................................................................................................................53General tab............................................................................................................................................................................... 53Display within Zoom Scale tab.................................................................................................................................................. 54Labels tab................................................................................................................................................................................. 54

About the Thematic Layer Properties dialog box ....................................................................................................................... 54General tab............................................................................................................................................................................... 54Display tab ................................................................................................................................................................................ 55Display within Zoom Scale tab.................................................................................................................................................. 55Labels tab................................................................................................................................................................................. 55

About the RST Properties dialog box .......................................................................................................................................... 55About the Modify dialog box...................................................................................................................................................... 56

About the Symbol Properties dialog box .....................................................................................................................................56Using the File Properties dialog box ............................................................................................................................................57

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About the Bitmap Properties dialog box ..................................................................................................................................... 57General tab............................................................................................................................................................................... 57History tab................................................................................................................................................................................. 57MetaData tab............................................................................................................................................................................ 57

About the File Properties dialog box ........................................................................................................................................... 58General tab............................................................................................................................................................................... 58History tab................................................................................................................................................................................. 59MetaData tab............................................................................................................................................................................ 59Projection tab............................................................................................................................................................................ 59

About the Ground Control Points dialog box ..............................................................................................................................61General tab............................................................................................................................................................................... 61History tab................................................................................................................................................................................. 61MetaData tab............................................................................................................................................................................ 62

About the Look-up Table Properties dialog box ......................................................................................................................... 62General tab............................................................................................................................................................................... 62History tab................................................................................................................................................................................. 63MetaData tab............................................................................................................................................................................ 63

About the Orbit Properties dialog box ......................................................................................................................................... 63General tab............................................................................................................................................................................... 63History tab................................................................................................................................................................................. 64MetaData tab............................................................................................................................................................................ 64

About the Pseudo-color table properties .................................................................................................................................... 64General tab............................................................................................................................................................................... 64History tab................................................................................................................................................................................. 65MetaData tab............................................................................................................................................................................ 65

About the Raster Properties dialog box ...................................................................................................................................... 65General tab............................................................................................................................................................................... 65History tab................................................................................................................................................................................. 66MetaData tab............................................................................................................................................................................ 66

About the Signatures Properties dialog box ............................................................................................................................... 67General tab............................................................................................................................................................................... 67History tab................................................................................................................................................................................. 67MetaData tab............................................................................................................................................................................ 67

About the Text Properties dialog box .......................................................................................................................................... 68General tab............................................................................................................................................................................... 68History tab................................................................................................................................................................................. 68MetaData tab............................................................................................................................................................................ 68

About the Vector Properties dialog box ...................................................................................................................................... 69General tab............................................................................................................................................................................... 69History tab................................................................................................................................................................................. 70MetaData tab............................................................................................................................................................................ 70

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Projection tab............................................................................................................................................................................ 70About the Other Projections dialog box.................................................................................................................................... 71

Color mapping and image profiles ............................................................................................................................................... 71About the RGB Mapping dialog box.......................................................................................................................................... 71Creating an image profile.......................................................................................................................................................... 72About the Profile Table dialog box............................................................................................................................................ 72About the Profile Options dialog box......................................................................................................................................... 74About the Profile Graph dialog box........................................................................................................................................... 74About the Graph Controls dialog box........................................................................................................................................ 76Using the graph controls........................................................................................................................................................... 77Exporting profiles...................................................................................................................................................................... 78Printing your graph without showing the mensuration bars...................................................................................................... 78

Using the View tools ...................................................................................................................................................................... 78Using the Zoom window............................................................................................................................................................ 78Using a Clone view................................................................................................................................................................... 78Chaining clone views................................................................................................................................................................ 79Zooming using the Overview window....................................................................................................................................... 79

Creating named regions ................................................................................................................................................................ 79Removing named regions......................................................................................................................................................... 80Creating named regions using coordinates.............................................................................................................................. 80

Panning an image .......................................................................................................................................................................... 80Zooming an image with zoom tools.......................................................................................................................................... 81Viewing a 1:1 image resolution................................................................................................................................................. 81

Using a layout grid .........................................................................................................................................................................81Grid spacing.............................................................................................................................................................................. 81Index spacing............................................................................................................................................................................ 82

Visualizing your data ..................................................................................................................................................................... 82Enhancing images.................................................................................................................................................................... 82Using the Attribute Manager..................................................................................................................................................... 83

Importing XML metadata using the METAIN algorithm .............................................................................................................. 83Opening an image data set ........................................................................................................................................................... 84Viewing global metadata ............................................................................................................................................................... 84Viewing band-specific metadata ...................................................................................................................................................85Enabling and disabling panes ...................................................................................................................................................... 85

Changing the units for the cursor position................................................................................................................................ 85Using the Visualization tools ........................................................................................................................................................ 85About the Visualization Tools dialog box ....................................................................................................................................86

Using the Flicker tool................................................................................................................................................................ 86Using the Swipe tool................................................................................................................................................................. 86Using the Blend tool.................................................................................................................................................................. 87Using the Loop tool................................................................................................................................................................... 88

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Using the Cycle tool.................................................................................................................................................................. 89Using the Band Cycling tool...................................................................................................................................................... 90

Opening the Thumbnails viewer ...................................................................................................................................................92About the Thumbnails viewer.................................................................................................................................................... 92Using the Thumbnails viewer.................................................................................................................................................... 94

Selecting grayscale and RGB layers ............................................................................................................................................95Visualizing data with the 3-D data cube .......................................................................................................................................95

About the 3-D data cube controls............................................................................................................................................. 96About the Select PCT Layer dialog box.................................................................................................................................... 98

Selecting colors ............................................................................................................................................................................. 99Color palettes............................................................................................................................................................................ 99

Color models .................................................................................................................................................................................. 99Setting options and preferences ................................................................................................................................................ 101

General interface.................................................................................................................................................................... 101Warnings................................................................................................................................................................................. 102Layers..................................................................................................................................................................................... 103Default representation............................................................................................................................................................. 103

Vector editing ............................................................................................................................................................................... 104Memory cache .............................................................................................................................................................................. 105

Optimizing the Undo/Redo options......................................................................................................................................... 106Optimizing the tiling cache...................................................................................................................................................... 106Setting the total cache limit..................................................................................................................................................... 107Setting the vector read cache................................................................................................................................................. 107

Overview window .........................................................................................................................................................................107Zoom window ............................................................................................................................................................................... 107Layer Manager ..............................................................................................................................................................................107Open GL settings ......................................................................................................................................................................... 108Setting shape and color preferences ......................................................................................................................................... 108

Modifying a selected line......................................................................................................................................................... 108Modifying a selected polygon.................................................................................................................................................. 109Applying preferences to selected text..................................................................................................................................... 109

Changing the style for hatches ...................................................................................................................................................109Changing the raster color........................................................................................................................................................ 110Changing the raster size......................................................................................................................................................... 110

Setting up a digitizing tablet using Wintab ................................................................................................................................110Setting up a digitizing tablet using a driver............................................................................................................................. 110Testing the digitizing tablet connection................................................................................................................................... 111Assigning text actions and modifiers....................................................................................................................................... 111

Setting up a GPS receiver ........................................................................................................................................................... 111Testing the GPS connection................................................................................................................................................... 112

Measurement tools ...................................................................................................................................................................... 112

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Changing display options ........................................................................................................................................................... 112About the Display Options dialog box..................................................................................................................................... 113

Customizing the Focus toolbars ................................................................................................................................................ 113About the Toolbar Configuration dialog box............................................................................................................................ 113

Supported layer types .........................................................................................................................................................................115Focus and raster layers ...............................................................................................................................................................115Metadata ........................................................................................................................................................................................116Segment organization ..................................................................................................................................................................116Topological layers ........................................................................................................................................................................120

Arc layers................................................................................................................................................................................ 120Node layers:............................................................................................................................................................................ 120Area layers.............................................................................................................................................................................. 120Representation Style Tables (RST)........................................................................................................................................ 121

Importing, linking, and translating data .....................................................................................................................................121Importing files to the PCIDSK format...................................................................................................................................... 122Building raster overviews........................................................................................................................................................ 123Deleting raster overviews........................................................................................................................................................ 123Linking PCIDSK and other databases.................................................................................................................................... 123Translating file formats............................................................................................................................................................ 124

Importing and converting ASCII files ......................................................................................................................................... 125Using the Import ASCII Table/Points wizard........................................................................................................................... 125Formating fixed width files...................................................................................................................................................... 126

Opening data from a remote data source .................................................................................................................................. 126Using undefined image data ....................................................................................................................................................... 127Image metadata support ..............................................................................................................................................................129Working with projections ............................................................................................................................................................ 129

Understanding PCIDSK projection definition.......................................................................................................................... 130Supported projections............................................................................................................................................................. 130Defining a new projection........................................................................................................................................................ 131Defining datums and ellipsoids............................................................................................................................................... 133

Reprojecting files .........................................................................................................................................................................134About the Reproject dialog box............................................................................................................................................... 134Reprojection bounds............................................................................................................................................................... 135Selectable layers and reprojection.......................................................................................................................................... 136Setting reprojection bounds.................................................................................................................................................... 137Specifying a coordinate system.............................................................................................................................................. 137

Selecting an ellipsoidal earth model .......................................................................................................................................... 137Selecting the earth model....................................................................................................................................................... 138

Selecting the SPCS coordinate system ..................................................................................................................................... 138Selecting a different coordinate system.................................................................................................................................. 138

Maximum bounds and resampling methods ............................................................................................................................. 138

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Selecting database layers for reprojection ................................................................................................................................139Organizing and editing layers .....................................................................................................................................................139

Adding and removing imagery................................................................................................................................................ 140Creating a new raster layer..................................................................................................................................................... 141Creating a new bitmap layer................................................................................................................................................... 141Creating a new vector layer.................................................................................................................................................... 141

Setting vector layer attributes .................................................................................................................................................... 142Setting vector layer properties ................................................................................................................................................... 142Transferring layers .......................................................................................................................................................................143Working with data tools ...............................................................................................................................................................144Changing data formats ................................................................................................................................................................ 144

About the Bitmap Save As dialog box..................................................................................................................................... 144About the Vector Save As dialog box..................................................................................................................................... 145Selecting GDB format options................................................................................................................................................. 145About the Grayscale Save As dialog box................................................................................................................................ 146About the Output Layer Properties dialog box........................................................................................................................ 147About the PCT Output Layer Properties dialog box................................................................................................................ 147About the RST Save As dialog box......................................................................................................................................... 147About the RGB Save As dialog box........................................................................................................................................ 148About the PCT Save As dialog box......................................................................................................................................... 149About the LUT Save As dialog box......................................................................................................................................... 150

Opening the Clipping/Subsetting panel .....................................................................................................................................151Clipping and subsetting images.............................................................................................................................................. 152Defining the clip region with user-entered coordinates ........................................................................................................... 153Defining the clip region by selecting a file............................................................................................................................... 153Defining the clip region by selecting a layer............................................................................................................................ 154Defining the clip region by selecting a named region............................................................................................................. 154Defining the clip region by selecting a script subset file.......................................................................................................... 154Creating the text file for the Script Subset File method........................................................................................................... 155Defining the clip region using the Zoom tools......................................................................................................................... 158Creating multiple subset tiles.................................................................................................................................................. 158Selecting a clip region............................................................................................................................................................. 158

Opening the Data Merge wizard ..................................................................................................................................................159Choosing an input layer.......................................................................................................................................................... 159Naming the output file............................................................................................................................................................. 159Setting up output layers.......................................................................................................................................................... 160

Data Merge wizard - Set Bitmap Parameters dialog box .......................................................................................................... 161Data Merge wizard - Set Image Parameters dialog box......................................................................................................... 161

Opening the Algorithm Librarian ....................................................................................................................................................... 163About the Algorithm Librarian dialog box ................................................................................................................................. 163Algorithm licensing ......................................................................................................................................................................163

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Algorithm categories ................................................................................................................................................................... 164Algorithm sub-categories........................................................................................................................................................ 164

Finding an algorithm ....................................................................................................................................................................166Using the Find Algorithm utility............................................................................................................................................... 166Searching for an algorithm by category.................................................................................................................................. 167

Creating user-defined categories ............................................................................................................................................... 167Adding algorithms to the user defined folder.......................................................................................................................... 168

Using an algorithm .......................................................................................................................................................................168About module control panels.................................................................................................................................................. 169

Finding help topics for all algorithms ........................................................................................................................................ 170Finding help from the Algorithm Librarian dialog box.............................................................................................................. 170Finding help from a Module Control Panel.............................................................................................................................. 170

Working with an algorithm MCP ................................................................................................................................................. 170Working with an example ............................................................................................................................................................ 171Using the ASP algorithm ............................................................................................................................................................. 171

Setting up the input port.......................................................................................................................................................... 171Setting up output ports............................................................................................................................................................ 171Setting up input parameters.................................................................................................................................................... 172Running the ASP algorithm..................................................................................................................................................... 172

Viewing the results ...................................................................................................................................................................... 172Understanding the results ...........................................................................................................................................................173Adding functions to the algorithm library ................................................................................................................................. 173

Starting a classification session ........................................................................................................................................................175Unsupervised classification ........................................................................................................................................................175

Configuring a new classification session................................................................................................................................ 175Initializing unsupervised classification.................................................................................................................................... 176Reading a classification report................................................................................................................................................ 176

Supervised classification ............................................................................................................................................................177The supervised classification process.................................................................................................................................... 177Initializing a supervised classification..................................................................................................................................... 178Specifying the reference image.............................................................................................................................................. 178

Specifying the input channels .................................................................................................................................................... 179Training sites and ground cover ................................................................................................................................................ 180Drawing a class training site .......................................................................................................................................................180

Making corrections.................................................................................................................................................................. 181About the Erase Settings dialog box....................................................................................................................................... 181

Changing training site colors ..................................................................................................................................................... 181Importing training sites ............................................................................................................................................................... 181

Importing vectors.................................................................................................................................................................... 182Opening the Import Bitmaps dialog box ....................................................................................................................................183

About the Import Bitmaps dialog box...................................................................................................................................... 183

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Importing a specified bitmap as its training site...................................................................................................................... 183Importing signatures from the training site editor ....................................................................................................................183Filling polygons using the Raster Seeding function ................................................................................................................ 184About the Raster Seeding dialog box ........................................................................................................................................ 184Filling a polygon ...........................................................................................................................................................................185Merging classes ........................................................................................................................................................................... 185Analyzing training sites ...............................................................................................................................................................185Testing signature separability .................................................................................................................................................... 186Testing separability with a scatter plot ......................................................................................................................................186Creating a scatter plot ................................................................................................................................................................. 187

Adjusting scatter plot threshold values................................................................................................................................... 187Altering the view range for the X and Y axes ............................................................................................................................ 187

Exporting the scatter plot file................................................................................................................................................... 187Displaying the color scale legend........................................................................................................................................... 187Printing the scatter plot........................................................................................................................................................... 188

Previewing the classification ...................................................................................................................................................... 188Setting the Maximum Likelihood classification preview.......................................................................................................... 188Removing the preview classification from the metalayer........................................................................................................ 188Creating a separability report.................................................................................................................................................. 188Saving the separability report to an existing file ......................................................................................................................189

Running a supervised classification ..........................................................................................................................................189Testing accuracy with signature statistics............................................................................................................................... 189Viewing signature statistics..................................................................................................................................................... 190Viewing a matrix report........................................................................................................................................................... 190Comparing signature statistics................................................................................................................................................ 190Saving the signature statistics report...................................................................................................................................... 190

Post-classification editing ...........................................................................................................................................................191Improving classification results............................................................................................................................................... 191Initialize post-classification editing.......................................................................................................................................... 191Setting up a bitmap mask....................................................................................................................................................... 191Opening a bitmap mask.......................................................................................................................................................... 192Saving a bitmap mask............................................................................................................................................................. 192Masking an image area........................................................................................................................................................... 192

Opening an aggregation session ............................................................................................................................................... 192Opening the Aggregate dialog box in an unsupervised session............................................................................................. 193Setting up an aggregation....................................................................................................................................................... 193Setting up a new aggregate class........................................................................................................................................... 193Creating an aggregate from a set of input classes................................................................................................................. 195Changing the input and output channel assignments............................................................................................................. 195Assigning a new PCT to the current session.......................................................................................................................... 195Generating a PCT................................................................................................................................................................... 196

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Importing a PCT...................................................................................................................................................................... 196Saving the aggregate session................................................................................................................................................. 196Starting an aggregate session................................................................................................................................................ 196Importing other classes........................................................................................................................................................... 197

Setting up for class labelling ...................................................................................................................................................... 197About the Class Labelling dialog box...................................................................................................................................... 198Initializing classes from a classification channel..................................................................................................................... 199Initializing classes from a text file............................................................................................................................................ 199Launching the Accuracy Assessment dialog box.................................................................................................................... 200

Using the Accuracy Assessment dialog box ............................................................................................................................ 200Selecting a classified image.................................................................................................................................................... 201Selecting a reference image................................................................................................................................................... 201Generating a random sample................................................................................................................................................. 201Assigning a reference class to a sample................................................................................................................................ 202Opening samples from a vector segment............................................................................................................................... 202Launching the Accuracy Report dialog box............................................................................................................................ 202Producing a random sample report......................................................................................................................................... 203Producing an error report........................................................................................................................................................ 203Producing an accuracy statistics report.................................................................................................................................. 203Saving an accuracy report...................................................................................................................................................... 203

Information tools .................................................................................................................................................................................205Opening the Information report .................................................................................................................................................. 205Viewing information for a selected vector .................................................................................................................................205Viewing information for vectors under the cursor ....................................................................................................................205Showing information for raster data .......................................................................................................................................... 206Displaying the attributes from a chart ....................................................................................................................................... 206Specifying the units of measurement ........................................................................................................................................ 206

Selecting a Measure tool........................................................................................................................................................ 206Measuring a line...................................................................................................................................................................... 207Measuring a polygon............................................................................................................................................................... 207Measuring a rectangle or ellipse............................................................................................................................................. 207Reading the Measure tool report............................................................................................................................................ 208

Viewing histograms and statistics ............................................................................................................................................. 208Viewing a histogram................................................................................................................................................................ 208Viewing histogram statistics.................................................................................................................................................... 209Viewing Mask contents........................................................................................................................................................... 209Viewing histograms under a bitmap mask.............................................................................................................................. 210Zooming into and out of a histogram...................................................................................................................................... 210Printing a histogram................................................................................................................................................................ 210Exporting a histogram............................................................................................................................................................. 210

Working with numeric values ..................................................................................................................................................... 211

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Opening the Numeric Values dialog box................................................................................................................................. 211Exporting the numeric values to a text file.............................................................................................................................. 212Change a color channel DN value.......................................................................................................................................... 212Interpreting the values............................................................................................................................................................ 212

Making an image profile .............................................................................................................................................................. 212Using the mensuration bars.................................................................................................................................................... 214Selecting vector profiles.......................................................................................................................................................... 214

Using the spectra extraction tools ............................................................................................................................................. 214Extracting spectra from a region of interest............................................................................................................................ 215About the Spectra Extraction Configuration dialog box.......................................................................................................... 215Configuring a hyperspectral metalayer................................................................................................................................... 215About the Spectra Extraction dialog box................................................................................................................................. 216

Region menu ................................................................................................................................................................................ 216Edit menu................................................................................................................................................................................ 217Tools menu............................................................................................................................................................................. 217Spectra extraction table.......................................................................................................................................................... 217About the Import Vectors dialog box....................................................................................................................................... 218About the Import Bitmaps dialog box...................................................................................................................................... 219

Merging a spectra channel ..........................................................................................................................................................220Saving a spectral extraction.................................................................................................................................................... 220

Plotting spectra ............................................................................................................................................................................221About the Spectra Plotting dialog box .......................................................................................................................................221

Radiometric quantity vs. wavelength graph............................................................................................................................ 221Displayed spectra................................................................................................................................................................... 222Graph options......................................................................................................................................................................... 224Plotting ranges........................................................................................................................................................................ 224Report..................................................................................................................................................................................... 225Selecting a spectra library....................................................................................................................................................... 225Changing the graph options.................................................................................................................................................... 226Saving a spectra plot.............................................................................................................................................................. 226

Opening the DEM Editing dialog box ......................................................................................................................................... 227Editing a DEM......................................................................................................................................................................... 227Opening an existing mask....................................................................................................................................................... 227Creating a mask...................................................................................................................................................................... 228Replacing the elevation values under a mask ........................................................................................................................ 228Filtering and interpolating DEM values................................................................................................................................... 229

Applying tool strategies for common situations in digital elevation models ........................................................................ 230Adjusting pixel values for a lake.............................................................................................................................................. 230Adjusting the pixel values for multiple lakes........................................................................................................................... 230Compensating for forests and urban areas............................................................................................................................. 230Neutralizing cloud-covered areas........................................................................................................................................... 231

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Removing noise from a DEM.................................................................................................................................................. 231Selecting the DEM layer......................................................................................................................................................... 231

Viewing the scatter plot for a layer .............................................................................................................................................232Changing the input channel for the X and Y axes: ..................................................................................................................233Using the Scatter Plot dialog box............................................................................................................................................ 233Zooming into and out of a scatter plot..................................................................................................................................... 234

Using the graph controls .............................................................................................................................................................234Changing the x and y view ranges.......................................................................................................................................... 234Exporting a profile................................................................................................................................................................... 235Working with legend and color controls.................................................................................................................................. 235

Interpreting a profile table ...........................................................................................................................................................235Changing the color of a channel ................................................................................................................................................ 236Changing the profile vector color ...............................................................................................................................................236About the Change Color dialog box ...........................................................................................................................................237Printing without the mensuration bars showing .......................................................................................................................237Using the profile statistics .......................................................................................................................................................... 238Controlling the cursor ................................................................................................................................................................. 238Opening the GPS tool .................................................................................................................................................................. 239

Using the GPS tool................................................................................................................................................................. 239Updating the cursor position using the GPS receiver............................................................................................................. 239Inputting vector point data using the GPS receiver................................................................................................................. 239Inputting vector line or polygon data using the GPS receiver................................................................................................. 240

Using the ADAPT algorithm ........................................................................................................................................................ 240Converting RGB to pseudo-color............................................................................................................................................ 241Converting RGB to pseudo-color............................................................................................................................................ 241Opening the PCT Editing dialog box....................................................................................................................................... 241Adjusting the pseudo-color for single values.......................................................................................................................... 241Editing a value........................................................................................................................................................................ 241Selecting a basic color value.................................................................................................................................................. 242

Customizing range-based pseudo-color tables ........................................................................................................................ 242Using standard mode.............................................................................................................................................................. 242Keeping the original color values............................................................................................................................................ 242Selecting colors within the range............................................................................................................................................ 242Applying pseudo colors to pixel values in a raster.................................................................................................................. 243

Opening the Raster Editing dialog box ......................................................................................................................................243Specifying a value ........................................................................................................................................................................244Changing a default enhancement ...............................................................................................................................................244Applying a linear enhancement .................................................................................................................................................. 244

Zooming an image feature with an enhancement................................................................................................................... 245Adjusting toolbar enhancements............................................................................................................................................. 246Applying the Tail Trim option.................................................................................................................................................. 246

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Adjusting the amount of Tail Trim........................................................................................................................................... 246Decreasing the image contrast............................................................................................................................................... 247Decreasing the image brightness........................................................................................................................................... 247Enhancing images from the shortcut menu............................................................................................................................ 247

Opening the LUT editor ............................................................................................................................................................... 247Displaying a histogram in the LUT Editor................................................................................................................................ 248Moving an entire histogram..................................................................................................................................................... 248Using the LUT tools................................................................................................................................................................ 248Using the LUT enhancement options...................................................................................................................................... 248Trace-editing a LUT histogram............................................................................................................................................... 249Comparing custom enhancements......................................................................................................................................... 249Applying a new look-up table to the corresponding image plane............................................................................................ 249

Working with spatial filters ......................................................................................................................................................... 250Opening the Filter dialog box.................................................................................................................................................. 250Filtering under a mask............................................................................................................................................................ 251Using low-pass filters.............................................................................................................................................................. 251Applying a gamma filter.......................................................................................................................................................... 253Using high-pass filters............................................................................................................................................................. 254Creating custom filters............................................................................................................................................................ 256Saving a filtered image to a new file....................................................................................................................................... 257

Scaling images .............................................................................................................................................................................257Scaling output data using Save As......................................................................................................................................... 258Available scaling methods...................................................................................................................................................... 258Scaling output data................................................................................................................................................................. 259

Fusing image data ........................................................................................................................................................................260Running the FUSE algorithm.................................................................................................................................................. 260Running IHS and RGB............................................................................................................................................................ 263Using the PANSHARP algorithm............................................................................................................................................ 263

Using the raster calculator ..........................................................................................................................................................265About the raster calculator ......................................................................................................................................................... 265

Expression.............................................................................................................................................................................. 266Edit.......................................................................................................................................................................................... 266View........................................................................................................................................................................................ 267Raster Calculator toolbar........................................................................................................................................................ 267Expression.............................................................................................................................................................................. 267Calculator keys....................................................................................................................................................................... 268Output parameters.................................................................................................................................................................. 268Using the Raster Calculator to set output parameters............................................................................................................ 269

Opening the EASI Modeling dialog box ..................................................................................................................................... 269About the EASI Modeling dialog box...................................................................................................................................... 270Adding image and bitmap layers to a .pix file......................................................................................................................... 271

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Using simple image models.................................................................................................................................................... 271Understanding the basic modeling logic................................................................................................................................. 272Adding a bitmap layer to irvine.pix.......................................................................................................................................... 273Image layer variables.............................................................................................................................................................. 274

Creating an EASI bitmap mask ................................................................................................................................................... 276Understanding atmospheric correction ............................................................................................................................................ 283

Preparing data ..............................................................................................................................................................................283Transfer data to PCIDSK........................................................................................................................................................ 283Reprojecting data.................................................................................................................................................................... 284Assembling data into a file...................................................................................................................................................... 285

Opening the Atmospheric Correction Configuration dialog box ............................................................................................ 285Setting up atmospheric correction parameters....................................................................................................................... 286

About aerosol types .....................................................................................................................................................................287About standard atmospheres ..................................................................................................................................................... 287Opening the elevation information setup dialog box ............................................................................................................... 288

Calculating slope, aspect, sky view, and shadow................................................................................................................... 289Opening the band setup dialog box ........................................................................................................................................... 289

Matching band numbers to channel numbers......................................................................................................................... 290Opening the Solar Calculations dialog box ...............................................................................................................................290

About Solar Zenith and Azimuth............................................................................................................................................. 290Calculating the solar zenith and azimuth................................................................................................................................ 290

About visibility ............................................................................................................................................................................. 291About adjacency..................................................................................................................................................................... 291Determining the offset to surface temperature value.............................................................................................................. 291

Editing an existing calibration file to create a new file .............................................................................................................292Opening the Define Haze and Cloud dialog box ....................................................................................................................... 293

Automatically creating a mask................................................................................................................................................ 293Importing the masks from a file............................................................................................................................................... 294

Editing the Cloud mask ............................................................................................................................................................... 294Editing the Haze mask ................................................................................................................................................................. 294Editing the Visibility layer ........................................................................................................................................................... 294Opening the Run Atmospheric Correction dialog box ............................................................................................................. 294

Running the correction............................................................................................................................................................ 295Deriving additional data from the corrected imagery.............................................................................................................. 295

Opening the Leaf Area Index Model dialog box ........................................................................................................................ 296Selecting the equation for calculating the Leaf Area Index..................................................................................................... 297

Changing the values for the fraction of photosynthetically active radiation (FPAR) equation ............................................297Opening the Advanced Option dialog box ................................................................................................................................ 297

Setting the parameters............................................................................................................................................................ 298Setting the thresholds for the reference pixels .........................................................................................................................299Opening the Empirical BRDF Correction dialog box ................................................................................................................299

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Selecting the BRDF equation.................................................................................................................................................. 300Understanding vector layer types ..................................................................................................................................................... 301

Unstructured vector layers ......................................................................................................................................................... 301About topological layers ............................................................................................................................................................. 301Thematic rasters .......................................................................................................................................................................... 302Understanding vector editing in a math model area ................................................................................................................ 302Adding a new vector layer ...........................................................................................................................................................303Adding points to an active layer .................................................................................................................................................303Adding a line or a polygon to an active layer ............................................................................................................................303Adding a rectangle or ellipse to an active layer ........................................................................................................................304Tracing a line on an active layer .................................................................................................................................................304Digitizing 3-D vectors .................................................................................................................................................................. 304Performing tasks in the Attribute Manager ............................................................................................................................... 304About the Preferences dialog box ..............................................................................................................................................305Controlling the Attribute Manager cursor ..................................................................................................................................305Setting a selected record statistics display .............................................................................................................................. 306Creating an unconnected table ...................................................................................................................................................306Restricting the layer so you cannot add shapes to it ...............................................................................................................306Viewing records ........................................................................................................................................................................... 307Opening a file saved as an attribute ...........................................................................................................................................307Selecting and clearing records and fields ................................................................................................................................. 307Understanding vector layer type default fields ......................................................................................................................... 307Adding records to the Attribute Manager .................................................................................................................................. 309Adding new fields ........................................................................................................................................................................ 309Setting the field definitions ......................................................................................................................................................... 309Changing an existing field to a geometry field ......................................................................................................................... 310Adding all appropriate geometry fields ..................................................................................................................................... 311Updating the geometry ................................................................................................................................................................ 311Using find and replace in the Attribute Manager ...................................................................................................................... 311Creating a relational database .................................................................................................................................................... 312Selecting all records that match a value in the current cell .....................................................................................................312Selecting all records that do not match a value in a selected field .........................................................................................313Making a query by example ........................................................................................................................................................ 313Limiting the query to selected records ...................................................................................................................................... 314Using the compute function ........................................................................................................................................................314Opening the Aggregate Attributes dialog box .......................................................................................................................... 315Performing a calculation ............................................................................................................................................................. 315Opening the Area Neighbors dialog box ................................................................................................................................... 315Reporting bordering areas .......................................................................................................................................................... 315Creating a chart from the Attribute Manager .............................................................................................................................316Opening the Z-value Transfer dialog box .................................................................................................................................. 317

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Transferring Z-values from the vertices to a field .....................................................................................................................317Transferring Z-values from a field to the vertices .....................................................................................................................318Exporting layer attributes to a file .............................................................................................................................................. 318Exporting the attributes to a text file ..........................................................................................................................................318Opening GeoRasters from the Attribute Manager .................................................................................................................... 319Dissolving a boundary .................................................................................................................................................................319Adding function fields to output layers ..................................................................................................................................... 320Working with shapes ................................................................................................................................................................... 320Selecting a single shape ............................................................................................................................................................. 321Selecting shapes within or partially within a circle .................................................................................................................. 321Selecting shapes within or partially within a polygon ..............................................................................................................321Grouping shapes ..........................................................................................................................................................................321Ungrouping shapes ..................................................................................................................................................................... 321Attaching shapes ......................................................................................................................................................................... 322Separating shapes ....................................................................................................................................................................... 322Creating buffers ........................................................................................................................................................................... 322Creating buffers - step 1 ..............................................................................................................................................................322Creating buffers - step 2 ..............................................................................................................................................................323Editing vectors using the vector editing tools .......................................................................................................................... 323About the Vector Editing tool bar ...............................................................................................................................................324Selecting a shape .........................................................................................................................................................................325Moving a vertex ............................................................................................................................................................................325Moving several vertices together while maintaining their form .............................................................................................. 325Reversing vector direction ..........................................................................................................................................................326Adding vertices ............................................................................................................................................................................ 326Connecting lines .......................................................................................................................................................................... 326Connecting polygons .................................................................................................................................................................. 326Cutting a line ................................................................................................................................................................................ 326Cutting a polygon .........................................................................................................................................................................327Extending a line ............................................................................................................................................................................327Merging segmented lines ............................................................................................................................................................ 327Changing a line into a polygon ...................................................................................................................................................327Flipping a shape to its mirror image .......................................................................................................................................... 327Spinning a shape free hand ........................................................................................................................................................ 328Spinning the shape precisely ..................................................................................................................................................... 328Separating overlapping shapes ..................................................................................................................................................328Moving the cursor to the start vertex .........................................................................................................................................328Moving the cursor to the end vertex: ......................................................................................................................................... 329Moving the cursor along vertices ...............................................................................................................................................329Moving the cursor to a vertex ..................................................................................................................................................... 329Displaying vertices ...................................................................................................................................................................... 329

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Adding and removing: vertices .................................................................................................................................................. 329Switching between coordinate systems .................................................................................................................................... 330Selecting vectors using spatial query tools .............................................................................................................................. 330Including an original selection in a spatial query ..................................................................................................................... 330Selecting fully contained shapes ............................................................................................................................................... 330Selecting partially contained shapes ......................................................................................................................................... 330Selecting all shapes within a specified distance ...................................................................................................................... 331Selecting all shapes fully within a distance .............................................................................................................................. 331Selecting intersecting shapes .................................................................................................................................................... 331About the Overlay wizard ............................................................................................................................................................ 331Combining layers with a spatial overlay ....................................................................................................................................332Using a statistical overlay ...........................................................................................................................................................333Adding attributes to the statistical overlay output ................................................................................................................... 333Using a suitability overlay ...........................................................................................................................................................334Understanding weights in the suitability overlay ..................................................................................................................... 336Viewing data as a chart ............................................................................................................................................................... 337About chart types .........................................................................................................................................................................337Creating a chart from the layer ................................................................................................................................................... 339Defining the data to chart ............................................................................................................................................................340About Series In .............................................................................................................................................................................340Designing the chart surround .....................................................................................................................................................341About the category field .............................................................................................................................................................. 342Resetting the chart to defaults ................................................................................................................................................... 343Using the Chart Viewer ................................................................................................................................................................343Designing the chart legend ......................................................................................................................................................... 345Opening the X-axis or Y-axis Properties dialog box .................................................................................................................345Customizing the axis heading .................................................................................................................................................... 346Customizing the axis tick labels .................................................................................................................................................346Opening the X-axis or Y-axis Properties dialog box .................................................................................................................346Displaying grid lines along the axis ........................................................................................................................................... 347Displaying ticks ............................................................................................................................................................................347Opening the Title or Subtitle Properties dialog box ................................................................................................................. 347Customizing the title or subtitle of the chart .............................................................................................................................347Opening the data labels properties ............................................................................................................................................ 347Customizing the data labels ........................................................................................................................................................348Saving a chart ...............................................................................................................................................................................348Opening and deleting a chart ......................................................................................................................................................348Digitizing vectors with peripheral devices ................................................................................................................................ 349Registering a digitizing tablet ..................................................................................................................................................... 349Importing and exporting tablet registration .............................................................................................................................. 350Using a digitizing tablet ...............................................................................................................................................................350

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Using the GPS tool .......................................................................................................................................................................351Inputting vector point data using a GPS receiver .....................................................................................................................351Inputting vector line or polygon data using the GPS receiver ................................................................................................ 352Understanding representation ....................................................................................................................................................352Types of representation style tables ..........................................................................................................................................353Generating an indirect representation style table .................................................................................................................... 354Editing the representation styles ............................................................................................................................................... 354Selecting a style ...........................................................................................................................................................................354Changing style appearance ........................................................................................................................................................ 355Changing style parts ....................................................................................................................................................................355Using an attribute as part of the style ........................................................................................................................................355Opening the Set Style Attribute dialog box ............................................................................................................................... 356Setting the style attribute ............................................................................................................................................................ 356Selecting a symbol .......................................................................................................................................................................356Labelling shapes ..........................................................................................................................................................................356Managing the labels .....................................................................................................................................................................356Adding labels to a layer ...............................................................................................................................................................357Setting label representation ........................................................................................................................................................357Changing labels ........................................................................................................................................................................... 357Defining the design and layout for labels ..................................................................................................................................358Defining which attribute to use for the label ............................................................................................................................. 358Setting the position for point layer labels ................................................................................................................................. 359Setting the position for line layer labels .................................................................................................................................... 359Setting the position for polygon and raster layer labels ..........................................................................................................360Designing a symbol ..................................................................................................................................................................... 360Understanding the symbol working area ...................................................................................................................................360Creating a symbol ........................................................................................................................................................................361Creating a multi-part symbol ...................................................................................................................................................... 361Selecting a symbol from the symbol file ................................................................................................................................... 362Setting symbol representation ................................................................................................................................................... 362Editing the symbol RST ...............................................................................................................................................................362About the symbol file Save As dialog box .................................................................................................................................362

Saving a project file ............................................................................................................................................................................ 365Renaming a map .......................................................................................................................................................................... 365Starting a new map ...................................................................................................................................................................... 365Working with map properties ......................................................................................................................................................365Changing the paper size by dragging a resize handle ............................................................................................................. 365Changing the paper size from the Map Properties dialog box ................................................................................................ 366Working with areas ...................................................................................................................................................................... 366Scaling an area .............................................................................................................................................................................367Rescaling an area .........................................................................................................................................................................367

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Setting area properties ................................................................................................................................................................ 368Setting area properties ................................................................................................................................................................ 368Opening the Math Model Area Properties dialog box ...............................................................................................................369Setting Math Model Area properties ...........................................................................................................................................370Working with surrounds ..............................................................................................................................................................371Creating a surround .....................................................................................................................................................................371Setting a default surround element ............................................................................................................................................372Setting a default quick style ........................................................................................................................................................372Setting surround element properties ......................................................................................................................................... 372About neatlines ............................................................................................................................................................................ 372Setting the position of a neatline in relation to an area ........................................................................................................... 372Setting specific extents for a neatline ........................................................................................................................................373About borders .............................................................................................................................................................................. 373Changing border style and proximity to neatline ..................................................................................................................... 374About grids ...................................................................................................................................................................................374Changing grid pacing and proximity to neatline .......................................................................................................................375Changing the style and layout of the grid ................................................................................................................................. 376Changing the location and style of the grid headings ............................................................................................................. 377Changing the location and style of the grid labels ................................................................................................................... 377About legends .............................................................................................................................................................................. 379Setting the number of columns and designing a border for a legend .................................................................................... 380Adding a title to the legend ......................................................................................................................................................... 380Adding styles to a legend ............................................................................................................................................................381Organizing sections in a legend ................................................................................................................................................. 382Creating a design for sections in a legend ................................................................................................................................383Customizing a section layout ..................................................................................................................................................... 384Organizing legend columns ........................................................................................................................................................ 384Adding a picture to a map ........................................................................................................................................................... 385About north arrows ......................................................................................................................................................................386Setting the angle and style for a true North arrow ....................................................................................................................386Adjusting the position of a north arrow label ............................................................................................................................387Setting the angle and style for the magnetic north arrow ........................................................................................................387Setting the angle and style for the grid north arrow .................................................................................................................388About scale bars .......................................................................................................................................................................... 388Determining the style and position of the title for the scale bar ............................................................................................. 389Selecting a scale bar type ........................................................................................................................................................... 390Setting the divisions for the scale bar ....................................................................................................................................... 390Labeling a scale bar with a unit of measurement and setting a zero tick .............................................................................. 391Setting subdivisions for a scale bar ...........................................................................................................................................392Specifying which divisions to subdivide ................................................................................................................................... 392Designing a Line and Tick scale bar .......................................................................................................................................... 393

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Designing a single, double, or triple scale bar ..........................................................................................................................393Adding a map title to an area ...................................................................................................................................................... 394Adding text to a surround ........................................................................................................................................................... 395Setting the updating behavior .................................................................................................................................................... 395Setting the offset (not available for neatline, border, and grid) ...............................................................................................396Setting a grid starting point ........................................................................................................................................................ 396Selecting an existing quick style ................................................................................................................................................397Removing a custom quick style from the list ............................................................................................................................397Creating a custom quick style .................................................................................................................................................... 397Creating an index for a project, you must provide ................................................................................................................... 397Adding a default index to a map .................................................................................................................................................398Indexation properties ...................................................................................................................................................................398Setting general parameters for an index ................................................................................................................................... 398Adding or change the index title ................................................................................................................................................ 399Opening an indexation parameter file ........................................................................................................................................399Setting up an index ...................................................................................................................................................................... 400Setting the spacing for rows and columns ................................................................................................................................400Setting the count for rows and columns ................................................................................................................................... 400Setting headings for rows and columns ....................................................................................................................................401Setting a RepCode for a grid heading ........................................................................................................................................401Setting a RepCode for grid lines ................................................................................................................................................ 401Filtering an index ......................................................................................................................................................................... 401Making a word exclusion list ...................................................................................................................................................... 401Generating an index list .............................................................................................................................................................. 402Using the Verification Mode option ............................................................................................................................................402Setting advanced indexation properties ....................................................................................................................................402The prefixes list follows a set of rules ....................................................................................................................................... 403Creating or editing a prefixes list ............................................................................................................................................... 403Using the Swap Prefixes option ................................................................................................................................................. 404Saving an indexation file ............................................................................................................................................................. 404Adding text to an index ............................................................................................................................................................... 404Setting the text color ................................................................................................................................................................... 404Setting the text style .................................................................................................................................................................... 404Using the New Text tool .............................................................................................................................................................. 404Printing a map .............................................................................................................................................................................. 404Selecting printer options .............................................................................................................................................................405Selecting page layout options .................................................................................................................................................... 405Printing color separations ...........................................................................................................................................................405Opening the Export Map dialog box ...........................................................................................................................................407Exporting a map or chart as an Adobe Illustrator file .............................................................................................................. 408Exporting a map or chart as a JPEG .......................................................................................................................................... 408

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Exporting a map or chart to a JPEG 2000 file ........................................................................................................................... 409Exporting a map or chart to PCIDSK ..........................................................................................................................................409Exporting a map or chart to TIFF ................................................................................................................................................409Exporting a map or chart to BMP ............................................................................................................................................... 410Exporting a map or chart to an HP RTL file ...............................................................................................................................410Exporting a map or chart to EMF ................................................................................................................................................411Viewing overlapping layers from a Web mapping service .......................................................................................................411

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Chapter 1Using the Focus online helpThe Focus HTML online Help system provides basic Helptopics for using Focus and online references for theFocus tools and processes you will need to use when youdo your work. Geomatica Help includes a technicalreference library for background information andextensive online list of data formats you can use with themany PCI GeoGateway features in Focus. You can alsocontact PCI or visit the PCI Geomatics Corporate Website for more specific help and support.

Using technical referencesThe Geomatica online Help system includes TechnicalReferences you can access from Focus online Help.

Technical references are available for:

GeoGateway formats:

Provides information on working with large files, thePCIDSK file structure, and supported file formats.

Projection Reference:

Provides a complete list of projections supported by

Focus and the other Geomatica applications.

Advanced Hyperspectral:

Contains detailed technical information on hyperspectraldata and how you can use it with Focus and the otherGeomatica applications. For information on using theFocus hyperspectral visualization tools, see the FocusOnline Help and the Focus User Guide.

Using the GDB formats referenceGeoGateway (GDB) is a technology allowing programs touniformly access data in many different geomatics fileformats without having to translate them before you usean application. GeoGateway lets you access imagery,vectors, attributes, projections and auxiliary information.All important data types, and access approaches from thegeneric GeoGateway Data Model are implemented withinthe GeoGateway library.

Not all file formats support all data types, or accessapproaches. Only PCIDSK, the format on which theGeoGateway Data was modelled, supports all possibledata types. Many formats have limitations that may effectyour productivity when using Focus and other Geomaticaapplications.

The GDB Formats reference topics describe each format,including any limitations. The complete list of DGBformats is included in the Geomatica online Help systemunder the Supported File Formats topic. You can open aHelp screen for a specific format from the main

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Supported File Formats screen by clicking the name ofthe format in the supported formats list.

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Chapter 2Working with FocusLike all PCI Geomatics products, Focus is designed towork with dozens of data formats through GeoGatewayand to take advantage of the PCIDSK file format. Thereare several instances when you should change your datato PCIDSK so you can take advantage of all of thefeatures offered in Geomatica.

You should convert your data files to PCIDSK formatwhen:

• The original format does not support auxiliaryinformation, such as georeferencing, look-up tables,pseudo-colour tables, and vectors.

• The original format cannot be updated.• You want to use your files in PACE or XPACE

programs.

Geomatica also contains a certified implementation of theNITF standard enabling you to view, to format, and toexport digital imagery and imagery-related products;Geomatica is, however, not NITF certified.

Opening a file

You can open files in Focus from the File menu, from thetoolbar, or from shortcut menus in the Focus control pane

under both the Files tab and the Maps tab. You canchoose files from the File Selector dialog box, which is astandard Windows panel that also allows you to choosefrom data types in the GeoGateway file list (GDBformats). For more information on the File Selector dialogbox, see "Common Utilities" in the Geomatica onlineHelp.

The following image shows the main Focus interface:

When you open data files, they are listed in the Files treein the control pane and all files and layers are available.For more information about elements in the Focus

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interface, see Understanding the Focus control pane onpage 27 .

1. From the File menu, click Open.

You can also right-click in the Maps control paneand click Open.

2. In the File Selector dialog box, locate and selectyour data files.

3. Click Open.

The image data opens in the view pane. The firstthree image channels are automatically selected.The file components are listed in the Maps andFiles control panes. If the file you opened does nothave raster data, the first vector layer opens in anew map.

Note: For colour images, TM Bands 1, 2, and 3representing the red, green, and blue (RGB) imagechannels, are listed in the Maps tree under New Area.

When you open an image containing a math modelsegment, you can choose to use the a georeferencing ormath model. For more information, see Using a mathmodel with images on page 40 .

Adding data to a project

You can add data to a project in several ways. Themethod you use may depend on your objectives. You canuse the Files menu to add as many new files to a projectas you want in the same way as you would any other

Windows-based application. Focus also provides an AddLayer Wizard to make adding data easier, see Using theAdd Layer wizard on page 26 .

You can also add files to open data. For example, youcan add new vectors to an Area already in use or you cancreate a new empty layer and add new data to it bydragging data from another Area or from a differentdatabase using the Add Layer Wizard.

When you add more data to a project, it is automaticallyadded to the Focus Maps tree in an active Area.

1. In the Maps tree, right-click a Map and click NewArea.

2. Drag the data you want to move into the new Area.3. Save the project.

You can also add files from the Files tree to theMaps tree from an open database.

Using the Add Layer wizard

When you want to add layers from otherGeoGateway-supported data sets, you can add vector,RGB, grayscale, pseudo-color, and bitmap layers to aproject with the Add Layer Wizard. The Add Layer Wizardhelps you locate the exact layers you want and guidesyou through the process of adding the layer types youspecify.

When you move to the next step in the wizard, thecommands shown in the lower part of the dialog boxchange according to the data type you are adding. When

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you use the Add Layer Wizard, you do not need to havean active Area in the Maps tree; the Wizard creates anew layer automatically.

1. In the Maps tree, right-click the area where youwant to add a layer and click Add.

You can also click Add from the Layer menu.

2. From the Add Layer Wizard, choose a layer typeoption and click Next.

3. From the Files available list, select the data filecontaining the raster channels you want to use.

If the raster file you want to use is not listed, clickBrowse, navigate to the file you want, and click OK.

When you have selected a file in the Files availablelist, only channels of the specified type are listed inthe The following vector segments are availablelist. For example, only bitmap channels are listed ifyou have selected bitmaps as the layer type youwant to add.

4. From the The following vector segments areavailable list, select the channel you want to use inyour layer.

5. Click Finish.

Understanding the Focus controlpaneWhen you begin a work session, a Map, Area, and layerare automatically listed in the Maps tree using default filenames and paths. By default, new Map layers arelabelled Unnamed Map. Both the Map and layer levels

show the name and path of the file you have opened. TheArea level is named New Area by default. You canrename each level and each layer as needed. You caninclude files of almost any format in your project. In somecases, you may need to convert your file formats to thePCIDSK.

Maps

Are the element at the top of the hierarchy. This is theworkspace that holds all of the data for your work, suchas the image, surrounds, and indexes. You can havemore than one map in a project. The Map represents theextents of the print page for your project. You can adjustthe map size to control the size of your printed output oradjust the size and position of the image relative to thecanvas.

Areas

Hold the file boundaries for either image or vector layers.You can include several layers and segments for ageographical region and you can have many areas in aMap. Each Area has a unique georeference system.When an image or vector layer is added to an area, it isautomatically scaled and georeferenced to that Area.

Layers

Hold the data displayed in the view pane. Layers arecomposed of segments and can be rearranged in theMaps tree to change the image in the view pane. You canchange the order of layers by dragging them up or downthe Maps tree. When you move a layer, you also move

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the segments within it.

Segments

Are all of the components that make up a layer, such asrasters, vectors, bitmaps, and look-up tables (LUT).

The files, listed in the Maps tree, are a hierarchy ofelements that make up a project. Maps tree elementshave common properties that you can control from theMaps and Files tree, menu bars, and shortcut menus.

Using the Maps and Files treesYou can create, select, read, and write both image andauxiliary information to the items listed in the Maps andFiles trees. The control pane uses the GeoGatewaylibrary to access both image and auxiliary informationwithin your data files. GeoGateway makes it possible foryou to interchange different file types, includingthird-party file formats. To access a file, select it in theFiles tree.

Changing the layer priority

The Maps tree lists the areas, layers, channels, andsegments that make up the image in the view pane. TheMaps tree components are stored in your systemmemory. You can hide an item in the Maps tree bydisabling the check box to the left of the item. You canalso change the priority of a layer by dragging it up ordown the Maps tree. Layer priority can cause one layer tomask another in the view pane. If you cannot see a layer

that should be visible, check the layer priority.

1. In the Maps tree, click an Area layer.2. Drag the layer up or down the Maps tree.

A black line shows the layer position.

You can move an entire area, including associatedcomponents, in the same way.

Viewing layer properties

You can view the properties for any Map, Area, or layer.For more information about properties, see the following:

• Managing data properties on page 35• Using the File Properties dialog box on page 57

1. In the Maps tree, click a Map icon.2. From the View menu, click Properties.

For information on working with layers, see Using theLayer Manager on page 31 .

Viewing auxiliary data

The figure below shows some of the contents of a .pixfile, grouped by data type, in the Files tree. You can showor hide the vector and bitmap segments, listed in theFiles tree, in the view pane.

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The Files tree lists data saved to your hard disk

Like the PCIDSK format, Focus keeps image channelsand auxiliary data segments in the same place. The datalisted in the Files tree is stored in the source file on yoursystem hard disk.

Some of the data types, listed in the Files tree, are notviewable as image components. The same list cancontain other auxiliary data types such as LUTs,pseudo-color tables (PCT), and signatures. You can usethe Focus software tools and dialog boxes to work withthese data types.

Adding image channels

You can add 8-bit, 16-bit signed, 16-bit unsigned, or32-bit real image channels to a selected PCIDSK file. Bitdepth (also called pixel depth) refers to the range ofnumeric values stored in image layer data. The range ofnumbers each pixel can store increases with bit depth.

About the Add Image Channels dialog box

The Add Image Channels dialog box opens when youright-click an unlocked file in the Files tree and lets youset the following attributes:

Supported bit depths are:

• 8-bit: 0 to 255• 16-bit signed; -32,768 to + 32,786• 16-bit unsigned: 0 to 65,535• 32-bit real: approximately +/-1.2E-38 to 3.4E+38

Channel Types:

Lists the supported image pixel depths.

Existing:

Displays the number of image channels for each pixeldepth in the selected file.

Channels to Add:

Lets you specify the number of image channels of eachtype that you want to add to the source file.

When your source PCIDSK file channels are arranged aseither band sequential or file interleaved, new channelsare added to the end of the file. When your files are pixelinterleaved, the new channels are added in groups ofpixel depth. Pixel depth groups are ordered by size.

For example, when you add 8-bit channels to an existingpixel interleaved file with 16-bit unsigned channels, the8-bit channels are listed first. Existing 16-bit unsignedchannels are renumbered as subsequent channels.

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Combining layers

A combined vector layer amalgamates several vectorlayers into one. For example, one vector layer coveringthe eastern US can be combined with another layercovering the western US to produce a virtual single layerfor all of the US. When you combine layers, data is notduplicated, it is linked. The combined layer does not storedata but acts as a pointer to the source data.

You can combine vector layers from your current datafiles and from other source files with a two-part processto locate and choose the data you want to combine.

1. With at least two PCIDSK files open in the controlpane, click the Files tab.

2. In the Files tree, right-click the file folder icon andclick New and then click Combined Vector Layer.

3. In the Combined Layer dialog box, click Browse.4. From the Select Layer dialog box, select a file from

the File list box.5. Select an available layer from the Layers available

list.6. Click OK.

The layers and common columns are listed in theCombined Layer dialog box.

The Layer list shows two or more entries that youcan combine.

The Common attributes list identifies the columns(fields/attributes) that will make up the combinedlayer doesn't require any action. Only columns that

are present in all layers of your inputs are listed.

7. In the Combined Layer dialog box, select a layerand click OK.

A new layer is added under the files listed in the Filestree. You can view the new layer and see the combineddata in the view pane. You can also open the AttributeManager to see all of the combined shapes. Layerscommon to both input layers are listed twice.

For more information, see the following:• About the Combined Layer dialog box on page 30• About the Select Layer dialog box on page 31

About the Combined Layer dialog box

The Combined Layer dialog box provides a list of layersand common columns in separate windows that allow youto combine layers.

Layer List:

Shows the layers you have chosen from the Select Layerdialog box.

Browse:

Opens the Select Layer dialog box, allowing you tochoose layers and source files. (See About the SelectLayer dialog box on page 31 )

Remove:

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Removes a selected layer from the Layer list.

Common Columns List:

Shows columns that are common to layers in the Layerlist.

About the Select Layer dialog box

The Select Layer dialog box lets you choose the filescontaining the layers you want to combine.

File List:

Shows the files currently in a project from which you canselect layers.

Layer List:

Shows the layers within selected files in the Files list.

Working with project filesFocus project files (.gpr files) provide a way for you toorganize data for complex projects in one large file. A.gpr file not only stores Maps, Areas, and layers, but alsoincludes all path information to data, viewing preferences,such as the last zoom level you worked at, and allassociated Map elements. A .gpr file can also includemultiple Maps, Areas, and all associated layers.

Files included in a project are listed in the Files tree in thecontrol pane. All files and layers are available for use in a

project at any time. You can use any of the Focusviewing and editing options when working with .gpr files.You can also manage RGB and grayscale layers withinproject files with shortcut menus in the Maps and Filespanes.

When you right-click an object in the Files tree, a shortcutmenu lists the available commands for working with thatdata type. For example, right-clicking a file folder iconopens a shortcut menu listing several commands formanaging files. Right-clicking an RGB or grayscale layeropens a shortcut menu listing commands for managingthe layers as a data file and for adjusting attributes,statistical properties, and overviews for that layer.

Saving a project

When you work with multiple files, you can save yourwork as a project using the file name of your original datafiles or save your project under a new file name.

1. From the File menu, click Save Project or SaveProject As.

2. In the File Selector dialog box, navigate to thefolder where you want to store the project file.

3. Type a name for the project in the File name box.4. Click Save.

To save your project while you are working on it,click File and then click Save Project.

Using the Layer Manager

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The Layer Manager lists layer properties in a table formatthat shows properties for each object in the map and thehierarchical structure of Maps, Areas, and layers. Forsurrounds, the Layer Manager only displays the surroundelements. This tool is useful when you are trying tomanage a large combination of data layers, rasters, andvectors when making a map. Using the Layer Manger,you can control the vector layer hierarchy to ensure thatone project layer does not cover another.

• In the Layers menu, click Layer Manager.

Changing layer properties

In the Layer Manager table, object names are listed inrows. Object properties are listed in the table columns.Like the Maps and Files trees, icons are shown besideeach object in the Name column. Properties in the LayerManager show the state of layers in the current project.They can be changed according to the editable items forthe specific layers you are using.

Changes in the Layer Manager are automatically shownin the Maps tree. A layer must be open and the Map mustbe active to make changes. The check box indicatesactive layers and maps. The following lists the LayerManager table columns and explains the property cellsyou use to show, edit, open, and active properties forlayers.

Name:

You can edit this column and change the names of yourlayers.

Layer Visible:

Checked cells are visible layers. When the check box isdisabled, the layer is not visible.

Legend Items Visible:

Checked cells are Legend items that are visible. They aresimilar to the Layer Visible column but only apply tolayers in the legend.

Read Only:

Checked layers are read-only. When a layer is read-only,a red x will appear beside the layer under the Maps tab.

Layer Priority:

Cell numbers show the layer priority. A layer that isassigned a higher priority will be displayed on top of alayer with a lower priority. (See Changing the layerpriority on page 28 )

Zoom Scale Active:

Checked layers can be assigned zoom scale values.

Min Zoom Scale:

Minimum zoom scale value. As map scales go, thisparameter, X, is considered to be 1: X.

Max Zoom Scale:

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Maximum scale zoom value. As map scales go, thisparameter, X, is considered to be1: X.

Selectable:

Objects are selectable

Transparency Active:

Checked cells can be assigned a transparency value.When this check box is enabled, the values in theTransparency Value columns are active and the resultsare shown in Focus.

Transparency Value:

The pixel value entered here will become transparent,allowing you to see imagery under it. To properly assigntransparent values to a three-channel RGB image, usethe following format: R10G20B100. In this example, pixelvalue 10 will become transparent for the red band, 20 forthe green band, and 100 for the blue band. For grayscaleimages, you need only specify a singe value. Forexample: 10. The pixel value of 10 would becometransparent in your grayscale image.

Opacity Active:

When this check box is enabled, the values in theOpacity% column become active and the results areshown in Focus.

Opacity%:

Sets the opacity level. For example, 100% opacity showsthe entire image. Layers beneath cannot be seen. With asetting of 0%, none of the image is shown. You can seeall of an image beneath the layer.

View No Data Value:

Shows Null values.

No Data Color:

When there are #No Data# values in your working file,The No Data Color column lets you assign a color forviewing your No-Data pixels.

Using the Zoom Scale Active feature

When image data is opened, it is viewed at a specificscale (for example, 1:150000). The Zoom Scale functionlets you specify the resolution for activating specificlayers of imagery. When the current viewing resolution isin between the minimum and maximum values that youhave set for a layer, the image becomes visible. Whenthe current viewing resolution is outside the minimum andmaximum range you have set, the layer is not visible.

The Zoom Scale tool is useful when looking at bothhigh-resolution and low-resolution imagery of the samearea. For example, if you have a 30m Landsat image, a10m SPOT image and 1m aerial photo, all covering thesame area, you can view the Landsat image in Focus,but the aerial photo cannot be used because its pixelsare too small to render an accurate image. When you arezoomed into a ground feature using the aerial photo, the

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Landsat and SPOT scenes cannot be used because theirpixels are too large.

Using the Zoom Scale function you can set the zoomscale to deactivate the Landsat image when you arezoomed into the aerial photo, or deactivate the aerialphoto when you zoomed out looking at the Landsatscene. The following table shows the settings to use forthe example above.

Table 1.

Image Min Zoom Scale Max ZoomScale

Landsat (30m) 1:10 000 1:50 000

Spot (10m) 1:50 001 1:75 000

Aerial Photo (1m) 1:75 001 1:120 000

About rotated rastersMost raster (image) formats consist of a rectangular gridof pixels. However, some formats support raster rotation,which can display the raster as spun in a particularposition, usually so North is at the top of the viewer.Currently, PIX, GeoTIFF, MrSID and JPEG2000 canstore rotations internally. TIFF (with .tfw), JPEG (with.jpw), BIP (with .biw), BIL (with .blw) and NITF (with .niw)support rotations via their associated world file. Otherformats may support rotations via a PCI Geomatics .poxfile.

When you open a raster that contains a rotation, you willbe prompted to choose whether you want the raster todisplay as a rectangular grid (Raster Up) aligned with theArea or with the rotation from the file (North Up).

With the North Up option, the rotated raster opens as anyother raster. In the Focus view pane the raster mayappear turned in the Area since it has been corrected soNorth is at the top of the viewer.

A rotated raster as North Up

With the Raster Up option, the Area is rotated tocounteract the effect of the rotation in the file so the firstpixel in the data is in the top left corner of the Area. In theFocus view pane the raster appears squared to the Area.

A rotated raster as Raster Up

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When you create a map with a rotated Area (Raster Up),two surround elements are affected: Grid and NorthArrow. You cannot create a grid in a rotated Area. Whenyou create a North Arrow in a rotated Area, the NorthArrow will be rotated by the amount set in the Areaproperties.

Managing data properties

Properties are applied to data elements you have addedto your work and file elements that are saved to your harddisk. New and saved elements are listed under the Mapstree. Files, saved to disk, are listed under the Files tree.(See Using the File Properties dialog box on page 57 )

Properties are also applied to metadata files such aslook-up tables, pseudo-color tables, ground controlpoints, and signatures. When you are working with eitherproject files or .pix files, you can use the properties tocarry out basic operations like renaming and removingdata.

Properties dialog boxes have tabs with layer-specificsettings that you can adjust for the data type you areworking with. Properties dialog boxes always showinformation specific to the file and the file type you havechosen. Information and inputs vary depending on thetype of layer you have chosen.

1. In the control pane, click the Maps tab and select alayer.

2. From the View menu, click Properties.

You can also right-click a layer and clickProperties, or you can double-click a layer.

About the Map Properties dialog boxThe Map properties dialog box allows you to changeseveral attributes for your Map. You can re-name maps,review file information, and a select paper size andorientation for your map. You can also choose aRepresentation Style Table (RST).

(See General tab on page 35 )

General tab

Under the General tab, you can change genericinformation about your Map and read other fileinformation. (See Working with map properties on page 365)

Description:

Lets you change the file name or description appearing in

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the Maps tree.

File Name:

Reports the name of the Map file for the properties youare viewing.

Created:

Reports the date the file was created.

(See Page Setup tab on page 36 )

Page Setup tabUnder the Page Setup tab you can make page selectionsthat change the Map page orientation and size. You cansee your changes in the view pane from the Map viewmode. Your changes also affect the way your page isprinted. For more information, see the following:

• Changing the paper size by dragging a resizehandle on page 365

• Printing a map on page 404

Orientation:

Lets you select the way your Map appears on paper.Choose either the Portrait or the Landscape option.

Portrait:

Orients the map vertically

Landscape:

Orients the map horizontally

Paper Size:

Allows you to choose from a list of standard paper sizesor lets you create a custom size.

You can choose from the following paper sizeoptions:

• US Letter• US Legal• A0• A1• A2• A3 Tabloid• A4 Tabloid• A4 Letter• A5 Letter• B1 (ISO)• B4 (ISO)• B5 Letter• B 11" X 17"• C 17" X 22"• D 22" X 34"• E 34" X 44"• Custom

Width:

The Width box shows the dimensions of the standardpaper size you have chosen or allows you to enter acustom paper width of your own.

Height:

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The Height box shows the dimensions of the standardpaper size you have chosen, or allows you to enter acustom paper height of your own.

(See Default RST tab on page 37 )

Default RST tab

Under the Default RST tab you can select aRepresentation Style Table to use as the default for yourmap. RSTs that are associated with the map are listed inthe window. You can browse to locate and add an RST toyour map. (See Understanding representation on page 352)

About the Area Properties dialog boxThe Area properties dialog box allows you to changeseveral attributes for an Area. You can re-name maps,review file information, and change the Area scale,layout, and projection. You can also choose a new earthmodel for the Area projection. (See Setting Math ModelArea properties on page 370 )

Changing the values on the Area properties dialog boxdoes not change the data in the file on disk, it changesthe properties of the Area only.

(See General tab on page 37 )

General tabUnder the General tab you can change generic

information about your Area and preview the position ofyour area in relation to your map.

Description:

The Description box lets you change the Area name ordescription appearing in the Maps tree.

Show Outline:

The Show Outline option outlines the Area in the viewpane.

Scale:

The Scale box allows you to change the scale of yourArea to several standard scales or to a custom scale.

You can choose from the following scale options:

• 1:20000• 1:50000• 1:100000• 1:1000000• Custom

When you choose Custom from the scale list, you enteryour custom scale in the scale box.

Preview:

The Preview area allows you to see the scale andorientation of your Area relative to your map.

(See Layout tab on page 38 )

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Layout tabThe Layout tab lets you change the Area representation,position, and size. You can also view position and sizechanges in a preview window.

Representation:

Lets you change the Area scale factor and the Areapriority.

Scale Factor:

Changes the Area scale factor. (See Scaling an area onpage 367 )

Priority:

Changes the Area priority relative to other Areas in yourproject or file. (See Changing the layer priority on page28 )

Position:

Allows you to move your Area relative to the Map and toselect a unit of measure for your Area.

Left:

Allows you to change the Area position left or right.

Bottom:

Allows you to change the Area position up or down.

Size:

Allows you to control the width and height of your Area.

Width:

Changes the width of the Area.

Height:

Changes the height of the Area.

Automatic resize:

Resizes your Area automatically.

Preview:

Allows you to see the position and width and heightchanges for your Area relative to your map.

(See Projection/Extents tab on page 38 )

Projection/Extents tab

The Projection/Extents tab allows you to change thedefinition of the Area#s projection, change the bounds ofthe Area, and rotate the Area. Changing the projection'sdefinition does not change the projection of the Area. Tochange the projection, see Reprojecting files on page 134 .

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Coordinate System:

The Coordinate Systems list displays the coordinatesystem for your area.

The available coordinate systems are

• Pixel• UTM• Long/Lat• Meter• Foot• SPCS• Other

Earth Model:

The Earth Model button opens the Earth Model dialogbox, where you can choose from a list of data andellipsoids to define a coordinate system for an area.

More:

The More button opens projection definition dialog boxes,where you can select a projection definition for the Area.The More button is active if you select UTM, SPCS, orOther from the Coordinate System box. A differentprojection panel opens under different conditions.

Table 2.

This Projection Opens this panel

UTM Zone and Row

SPCS State Plane Zone

This Projection Opens this panel

Other Set the ProjectionDefinition

Bounds:

The Bounds box allows you to show the boundingcoordinates of you file in either geocoded (Eastings andNorthings) or geographic (latitude and longitude) units forUTM, SPCS and Other coordinate systems. Boundingcoordinates are not shown with the Pixel option. Long/Latdisplays the bounding coordinates in geographic unitsonly. Meter and Foot displays the bounding coordinatesin geocoded units only.

Upper left:

The Upper Left boxes show the X, Y coordinates for theupper left corner of the Area. Values are in the units ofthe selected coordinate system.

Lower Right:

The Lower Right boxes indicate the X, Y coordinates forthe lower right corner of the Area. Values are in the unitsof selected coordinate system.

Rotation:

The Rotation boxes indicate the amount the Area isrotated to display a rotated raster so the first pixel in thedata is in the top left corner. For more information, seeAbout rotated rasters on page 34 .

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Visual Clipping:

The visual clipping section lets you choose a clip regionfrom a list of clips that fall within your Area.

Define Clip Region:

The Define Clip Region button opens the Define ClipRegion dialog box.

Enable:

The Enable option is available after you have chosen aclip region from the Define Clip Region dialog box.

The Define Clip Region Panel:

Allows you to choose a clip region from a list of data thatfalls within the area.(See Opening theClipping/Subsetting panel on page 151 )

1. Right-click New Area and click Properties.2. In the Area Properties dialog box, click the

Projection/Extents tab.3. Click Define Clip Region.4. From the Define Clip Region dialog box, choose

the layer that you want to use to define the extentsof the clip region from the Clipping Layer list box.

5. Click OK.6. From the Visual Clipping area of the Area

Properties dialog box, enable the Enable checkbox.

7. Click OK.

Using a math model with images

A math model is a mathematical relationship used tocorrelate the pixels of an image to correct locations onthe ground accounting for known distortions. Differentsensors require different math models to correct thedistortions.

Math models can come from a number of sources.QuickBird, Ikonos, and OrbView imagery can come with atext file that contains rational function coefficients calledImage Geometry Model (IGM) or Rapid PositioningCapability (RPC), which Focus uses to define a RationalFunctions math model. You can build a math model inOrthoEngine and export it as a segment in the filecontaining a raw image. Geomatica also containsalgorithms that can build math models. These algorithmscan be run in Modeler, EASI, or in the AlgorithmLibrarian:

• SATMODEL: to compute Toutin's Model, which is arigorous satellite math model.

• RSMODEL: to compute the ASAR andRADARSAT-specific math model.

• RFMODEL to compute the Rational Functions mathmodel.

• AVMODEL: to compute the math model for AVHRRimagery.

• OEMODEL: to compute any model from anOrthoEngine project file.

When you open an image containing a math modelsegment, you can choose to use the file georeferencingor math model. When you choose file georeferencing, the

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image opens in a layer in an Area using thegeoreferencing saved in the file or pixel-basedgeoreferencing if no georeferencing is available. Whenyou choose the math model, the image is displayed as alayer and the Area is changed to a Math Model Area. Inthe Math Model Area the image is displayed withoutcorrection in the viewer, but accurate ground coordinatesare calculated for each pixel using the pixel and linecoordinates, the math model, and the digital elevationmodel (DEM), or an approximate elevation value that youprovide.

The advantage of using the math model is that you candisplay geocoded coordinates, overlay geocoded vectors,and digitize geocoded three-dimensional vectors on theraw image instead of going through the potentiallytime-consuming, labor-intensive process oforthorectifying or geometrically correcting the imagery.This process is also known as mono-restitution.

1. Open an image, see Opening a file on page 25 .2. If you want to use the georeferencing saved in the

file, click File.3. If you want to display the image using the math

model associated to the file, click Math Model.4. Click OK.

Using the math model forgeoreferencing

When a math model is used to set the georeferencing,the Area becomes a Math Model Area. In a Math ModelArea, the image is displayed without correction in theviewer; accurate ground coordinates are calculated for

each pixel using the pixel and line coordinates, the mathmodel, and the digital elevation model (DEM), or anapproximate elevation value that you provide. For moreinformation, see Using a math model with images onpage 40 .

1. In the Source of georeferencing list, select thesegment containing the math model that you wantto use in the Area.

The projection, bounds, upper-left coordinate,lower-right coordinate, and pixel sizes are displayedunder Georeferencing Information

2. To use a DEM as the source for your elevationvalues, click DEM.

In the File box, type the path and file name of theDEM or click Browse to select the file.

In the Layer list, select the layer that contains theDEM.

In the NoData (background) value box, type thevalue that represents the pixels that lie outside theDEM area so they are not mistaken for elevationvalues.

3. To use an estimate of the elevation instead of theDEM, click Approximate elevation.

In the Elevation value box, type the elevation valuethat you want to use. If you do not enter anelevation value, a value of 0 meters (Mean SeaLevel) is used by default.

4. In the Elevation reference box, select Mean Sea

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Level (MSL) if the elevation values were calculatedbased on the geoid; select Ellipsoid (ELL) if theelevation values were calculated based on anellipsoidal model of the Earth.

5. In the Elevation units box, select a measurementunit for the elevation values.

6. Click OK.

About the Math Model Area Propertiesdialog boxThe Math Model Area properties dialog box allows you toreview file information and change the scale and layout ofa Math Model Area. The georeferencing of the MathModel Area is based on a math model segmentassociated with a raw image rather than remainingpixel-based. For more information, see Setting MathModel Area properties on page 370 ).

(See General tab on page 37 )

General tab

Under the General tab, you can change genericinformation about your Math Model Area and preview theposition of your area in relation to your map.

Name:

The Name box lets you change the Math Model Areaname or description appearing in the Maps tree.

Show Outline:

The Show Outline option outlines the Math Model Area inthe view pane.

Scale:

The Scale box allows you to change the scale of a MathModel Area to several standard scales or to a customscale.

You can choose from the following scale options:

• 1:20000• 1:50000• 1:100000• 1:1000000• Custom

When you choose Custom from the scale list, you enteryour custom scale in the scale box.

Preview:

The Preview area allows you to see the scale andorientation of your Math Model Area relative to your map.

(See Layout tab on page 38 )

Layout tab

The Layout tab lets you change the Math Model Arearepresentation and position. You can also view positionchanges in a preview area.

Representation:

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Lets you change the Math Model Area scale factor andthe Math Model Area priority.

Scale Factor:

Changes the Math Model Area scale factor. (See Scalingan area on page 367 )

Priority:

Changes the Math Model Area priority relative to otherMath Model Areas in your project or file. (See Changingthe layer priority on page 28 )

Position:

Allows you to move your Math Model Area relative to theMap and to select a unit of measure for your Math ModelArea.

Left:

Allows you to change the Math Model Area position to theleft or right.

Bottom:

Allows you to change the Math Model Area position up ordown.

Size:

The Size section is always disabled in a Math Model

Area. The width and height of your Math Model Area aredetermined by the file.

Automatic Resize:

Automatically enlarges the extents of the Area toaccommodate the extents of the data.

Preview:

The Preview area allows you to see the position andwidth and height changes for your Math Model Arearelative to your map.

(See Projection/Extents tab on page 38 )

Projection/Extents tab

The Projection/Extents tab allows you to view the MathModel Area projection and select a clip of image data thatfalls within the area. It lists the file that contained themath model segment, the name of the segment, and thesource for the elevation values.

Projection

The coordinate system used in your Math Model Area isdisplayed.

Bounds

The Bounds list allows you to show the boundingcoordinates of your file in either geocoded (Eastings and

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Northings) or geographic (latitude and longitude) units forUTM, SPCS, and other coordinate systems.

Upper left

The Upper Left boxes show the X, Y coordinates for theupper-left corner of the file. Values are in the units of theselected coordinate system.

Lower Right

The Lower Right boxes indicate the X, Y coordinates forthe lower-right corner of the file. Values are in the units ofselected coordinate system.

Visual Clipping

The Visual Clipping section lets you choose a clip regionfrom a list of clips that fall within your Math Model Area.

Define Clip Region

The Define Clip Region button opens the Define ClipRegion dialog box, which allows you to choose a clipregion from a list of data that falls within the Math ModelArea. (See Selecting a clip region on page 158 )

Enable:

The Enable option is available after you have chosen aclip region from the Define Clip Region dialog box.

About the RGB Layer Properties

dialog boxThe RGB Layer Properties dialog box allows you tochange general properties, switch source images andlookup tables, adjust display properties, and set a zoomscale for your RGB layers.

(See General tab on page 44 )

General tab

Under the General tab, you can change generalinformation about your file and read other file information.

Description:

The Description box lets you change the file name ordescription appearing in the Maps tree.

Read Only:

The Read Only option lets you change the Read/Writeproperties of the RGB layer.

Visible:

The Visible option makes the RGB layer visible in theview pane.

Priority:

The Priority box changes the priority of the RGB layer inyour project or file. (See Changing the layer priority on

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page 28 )

Resample Method:

Allows you to select a resampling method for displayingthe raster in the Focus view pane. The resampling doesnot change the data itself, it is only used to determinehow to display the raster on your screen.

You can choose from the following resamplemethods:

• Nearest Neighbor• Bilinear Interpolation• Cubic Convolution

Layer Enhancement:

Reports enhancements associated with the RGB layer.(See Changing a default enhancement on page 244 )

(See Source Images tab on page 45 )

Source Images tab

Under the Source Images tab, you can select a new fileand a new image for the red, green, and blue channels.

RedImage:

Lets you select a new file and layer for the red imagechannel.

File:

Allows you to choose a different file from a list of files youhave open in Focus.

Layer:

Lets you to choose a layer from the file you chose fromthe RedImage File box.

GreenImage:

Lets you select a new file and layer for the green imagechannel.

File:

Allows you to choose a different file from a list of files youhave open.

Layer:

Lets you to choose a layer from the file you chose fromthe GreenImage File box.

BlueImage:

Lets you select a new file and layer for the blue imagechannel.

File:

Allows you to choose a different file from a list of files youhave open.

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Layer:

The layer list lets you to choose a layer from the file youchose from the BlueImage File box.

(See Source LUTs tab on page 46 )

Source LUTs tab

Under the Source LUTs tab, you can select a new fileand a new look up table for the red, green, and bluechannels.

RedLut:

Lets you select a new file and look up table for the redimage channel.

File:

Allows you to choose a different file from a list of openfiles.

Layer:

Lets you to choose a LUT from the file you chose fromthe RedLut File box.

GreenLut:

Lets you select a new file and look up table for the greenimage channel.

File:

The File list allows you to choose a different file from alist of files you have open in Focus.

Layer:

Lets you to choose a layer from the file you chose fromthe GreenLut File box.

BlueLut:

Lets you select a new file and look up table for the blueimage channel.

File:

Allows you to choose a different file from a list of files youhave open.

Layer:

Lets you to choose a layer from the file you chose fromthe BlueLut File box.

(See Display tab on page 46 )

Display tab

The Display tab has controls for changing thetransparency and opacity of the RGB layer and forviewing #No data# values when they are included in anRGB layer.

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Vector layers placed below a raster transparency in theMaps tree appear in the view pane but are not supportedfor printing.

Transparency:

Makes the Value boxes available.

Red Values:

Lets you enter a value or a range of values for redchannel transparency.

Green Values:

Lets you enter a value or a range of values for greenchannel transparency.

Blue Values:

Lets you enter a value or a range of values for bluechannel transparency.

Opacity:

Makes the Opacity slide control available for changingthe opacity of the RGB layer.

View 'No Data Value':

When an RGB layer contains 'no data' values, the View'No Data Value' option is available. When you choose theView 'No Data Value' option, you can select a color from

the color list for displaying them in the view pane.

(See Display within Zoom Scale tab on page 47 )

Display within Zoom Scale tabThe Display within Zoom Scale tab allows you to setindependent zoom limits for your RGB layer. When youzoom the view pane above the maximum scale or belowthe minimum scale, your RGB layer is no longer visible inthe view pane.

Minimum Scale:

Lets you enter a minimum zoom scale.

Maximum Scale:

Lets you enter a maximum zoom scale.

Current Zoom Scale:

Reports the current zoom scale for the RGB layer.

About the Grayscale Layer Properties dialogbox

The Grayscale Layer Properties dialog box allows you tochange general properties, switch source images andlookup tables, adjust display properties, and set a zoomscale for a grayscale layer.

(See General tab on page 48 )

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General tab

Under the General tab, you can change genericinformation about your file and read other file information.

Description:

Lets you change the file name or description for thegrayscale layer appearing in the Maps tree.

Read Only:

Lets you change the Read/Write properties of thegrayscale layer.

Visible:

Makes the grayscale layer visible in the view pane.

Priority:

Changes the priority of the grayscale layer in your projector file. (See Changing the layer priority on page 28 )

Resample Method:

Allows you to select a resampling method for displayingthe raster in the Focus view pane. The resampling doesnot change the data itself, it is only used to determinehow to display the raster on your screen.

You can choose from the following resamplemethods:

• Nearest Neighbor• Bilinear Interpolation• Cubic Convolution

Layer Enhancement:

Reports the enhancements associated with the grayscalelayer. (See Changing a default enhancement on page 244 )

(See Source Images tab on page 48 )

Source Images tab

Under the Source Images tab, you can select a new fileand a new image for the grayscale channels.

File:

Allows you to choose a different file from a list of files youhave open.

Layer:

Lets you to choose a layer from the file you chose fromthe grayscale file box.

(See Source LUTs tab on page 48 )

Source LUTs tab

Under the Source LUTs tab, you can select a new fileand a new look up table for the grayscale channel.

LUT:

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Lets you select a new file and look up table for thegrayscale layer.

File:

Allows you to choose a different file from a list of openfiles.

Layer:

Lets you to choose a LUT from the file you chose fromthe LUT file box.

(See Display tab on page 49 )

Display tab

The Display tab has controls for changing theTransparency and Opacity of the grayscale layer and forviewing #No data# values when they are included in agrayscale layer.

Vector layers placed below a raster transparency in theMaps tree appear in the view pane but are not supportedfor printing.

Transparency:

Makes the Value box available.

Values:

Lets you enter a value or a range of values for grayscale

channel transparency.

Opacity:

Makes the Opacity slide control available for changingthe opacity of the grayscale layer.

View 'No Data Value':

When a grayscale layer contains 'no data' values, theView 'No Data Value' option is available. When youchoose the View 'No Data Value' option, you can select acolor from the color list for displaying them in the viewpane.

(See Display within Zoom Scale tab on page 49 )

Display within Zoom Scale tab

The Display within Zoom Scale tab allows you to setindependent zoom limits for your grayscale layer. Whenyou zoom the view pane above the maximum scale orbelow the minimum scale, the grayscale layer is nolonger visible.

Minimum Scale:

Lets you enter a minimum zoom scale.

Maximum Scale:

Lets you enter a maximum zoom scale.

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Current Zoom Scale:

Reports the current zoom scale for the RGB layer.

Labels tab

The Label tab on the Properties dialog box for the layercontains the label files associated with the project. Formore information about labels see Managing the labelson page 356 .

About the PCT Layer Propertiesdialog boxThe PCT Layer Properties dialog box allows you tochange general properties, switch source images andpseudo-color tables, adjust display properties, and set azoom scale for the PCT layers.

(See General tab on page 50 )

General tab

Under the General tab, you can change genericinformation about your PCT layer and read other fileinformation.

Description:

Lets you change the file name or description for the PCTlayer appearing in the Maps tree.

Read Only:

Lets you change the Read/Write properties of the PCTlayer.

Visible:

Makes the PCT layer visible in the view pane.

Priority:

Changes the priority of the PCT layer in your project orfile. (See Changing the layer priority on page 28 )

(See Source Image tab on page 50 )

Source Image tab

The Source Image tab allows you to select a new PCTimage file and layer and a new pseudo-color table fileand layer.

PCTImage:

Lets you select a new file, layer, and PCT.

File:

Allows you to choose a different file from a list of files youhave open.

Layer:

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Lets you to choose a layer from the file you chose fromthe PCTImage file box.

PCT:

Lets you select a new pseudo-color table file and layer.

File:

Allows you to choose a different file from a list of files youhave open.

Layer:

Lets you choose a new pseudo-color table from the fileyou chose In the PCT file box.

(See Display tab on page 51 )

Display tab

The Display tab has controls for changing the Opacity ofthe PCT image layer and for viewing #No data# valueswhen they are included in a PCT image layer.

Opacity:

Makes the Opacity slide control available for changingthe opacity of the PCT image layer.

View 'No Data Value':

When a PCT image layer contains 'no data' values, the

View 'No Data Value' option is available. When youchoose the View 'No Data Value' option, you can select acolor from the color list for displaying them in the viewpane.

(See Display within Zoom Scale tab on page 51 )

Display within Zoom Scale tab

The Display within Zoom Scale tab allows you to setindependent zoom limits for your PCT layer. When youzoom the view pane above the maximum scale or belowthe minimum scale, your PCT layer is no longer visible inthe view pane.

Minimum Scale:

Lets you enter a minimum zoom scale.

Maximum Scale:

Lets you enter a maximum zoom scale.

Current Zoom Scale:

Reports the current zoom scale for the RGB layer.

Labels tab

The Label tab on the Properties dialog box for the layercontains the Label files associated with the project. Formore information about labels see Managing the labelson page 356 .

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About the Bitmap Layer Propertiesdialog boxThe Bitmap Layer Properties dialog box allows you tochange general properties, switch source files segmentnumbers and colors, adjust display properties, and set azoom scale for your bitmap layers.

(See General tab on page 52 )

General tab

Under the General tab, you can change genericinformation and read other file information about a bitmaplayer.

Description:

Lets you change the file name or description for thebitmap layer appearing in the Maps tree.

Read Only:

Lets you change the Read/Write properties of the bitmaplayer.

Visible:

Makes the bitmap layer visible in the view pane.

Priority:

Changes the priority of the bitmap layer in your project orfile. (See Changing the layer priority on page 28 )

(See Source Images tab on page 52 )

Source Images tab

Under the Source Images tab you can change yourbitmap layer source file and change your bitmap segmentand colors.

File:

Lets you choose a file from the list of open files.

Segment Number:

Lets you choose from the list of bitmap segmentsavailable in your open files.

Color:

Lets you change the color of the bitmap segment. Youcan choose from the following color options:

• Red• Blue• Cyan• Yellow• White• Black• More

The More option opens the Change Color dialog box,

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which lets you create a custom color.

(See Display tab on page 53 )

Display tab

The Display tab has controls for changing the Opacity ofthe bitmap segment.

Opacity:

Makes the opacity slide control available. You canchange the opacity of a bitmap segment when you wantto see data from another layer through the bitmap in theview pane.

(See Display within Zoom Scale tab on page 53 )

Display within Zoom Scale tab

The Display within Zoom Scale tab allows you to setindependent zoom limits for your bitmap segment. Whenyou zoom the view pane above the maximum scale orbelow the minimum scale, your bitmap segment is nolonger visible.

Minimum Scale:

Lets you enter a minimum zoom scale.

Maximum Scale:

Lets you enter a maximum zoom scale.

Current Zoom Scale:

Reports the current zoom scale for the bitmap segment.

About the Vector Layer Propertiesdialog boxThe Vector Layer Properties dialog box allows you tochange general properties, adjust display properties, seta zoom scale, and label vector layers. You can also addand remove metadata.

(See General tab on page 53 )

General tab

Under the General tab, you can change generic anddisplay information and read other file information about avector layer.

Generic:

Lets you change generic attributes of your vector layer.

Description:

Lets you change the layer file name or description of thevector layer shown in the Maps tree.

Read Only:

Makes the file read only. When you select this option you

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cannot save changes to the vector layer.

Visible:

Makes the vector layer visible in the view pane.

Selectable:

Allows you to select a vector in the view pane using theselection tools.

(See Display within Zoom Scale tab on page 54 )

Display within Zoom Scale tab

The Display within Zoom Scale tab allows you to setindependent zoom limits for your vector layer. When youzoom the view pane above the maximum scale or belowthe minimum scale, your vector layer is no longer visible.

Minimum Scale:

Lets you enter a minimum zoom scale.

Maximum Scale:

Lets you enter a maximum zoom scale.

Current Zoom Scale:

Reports the current zoom scale for the bitmap segment.

(See Labels tab on page 54 )

Labels tab

The Label tab on the Properties dialog box for the layercontains the label files associated with the project. Formore information about labels see Managing the labelson page 356 .

About the Thematic Layer Propertiesdialog boxThe Thematic Layer Properties dialog box allows you tochange general properties, adjust display properties, andset a zoom scale for the layers containing rasters with anRST.

(See General tab on page 50 )

General tab

Under the General tab, you can change genericinformation about your thematic layer and read other fileinformation.

Description:

Lets you change the file name or description for thethematic layer appearing in the Maps tree.

Read Only:

Lets you change the Read/Write properties of thethematic layer.

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Visible:

Makes the thematic layer visible in the view pane.

Selectable:

Allows you to select a thematic in the view pane using theselection tools.

Priority:

Changes the priority of the thematic layer in your projector file. (See Changing the layer priority on page 28 )

(See Display tab on page 51 )

Display tab

The Display tab has controls for changing the Opacity ofthe thematic image layer and for viewing #No data#values when they are included in a thematic image layer.

Opacity:

Makes the Opacity slide control available for changingthe opacity of the thematic image layer.

View 'No Data Value':

When a thematic image layer contains 'no data' values,the View 'No Data Value' option is available. When youchoose the View 'No Data Value' option, you can select acolor from the color list for displaying them in the view

pane.

(See Display within Zoom Scale tab on page 51 )

Display within Zoom Scale tab

The Display within Zoom Scale tab allows you to setindependent zoom limits for your thematic layer. Whenyou zoom the view pane above the maximum scale orbelow the minimum scale, your thematic layer is nolonger visible in the view pane.

Minimum Scale:

Lets you enter a minimum zoom scale.

Maximum Scale:

Lets you enter a maximum zoom scale.

Current Zoom Scale:

Reports the current zoom scale for the thematic layer.

Labels tab

The Label tab on the Properties dialog box for the layercontains the Label files associated with the project. Formore information about labels see Managing the labelson page 356 .

About the RST Properties dialog box

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The RST Properties dialog box lets you change severalaspect of an RST.

General Tab

Under the General tab, you can change the name of theRST file and change the current units of measure usedby the RST.

Description:

Lets you change the name of the RST.

Units:

Reports the units of measure used by the RST.

Modify:

Opens the Modify dialog box. (See About the Modifydialog box on page 56 )

File Information

The File information section shows the current path of theRST file and reports last date the file was modified.

File Name:

Reports the name and path of the RST.

About the Modify dialog box

From Ground To:

Lets you choose a different unit of measure, select astandard scale from a list, or create a custom scale.

Scale 1:

Lets you enter a custom scale when you choose Customfrom the From Ground To list.

About the Symbol Properties dialogboxThe Symbol Properties dialog box lets you change thedescription of a symbol file and view the symbol fileinformation.

General Tab

Under the General tab, you can change the name of thesymbol file and view the file information.

Description:

Lets you change the description of the symbol file.

File Information

The File information section shows the current path of thesymbol file and reports last date the file was modified.

File Name:

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Reports the name and path of the RST.

Using the File Properties dialog boxCharacteristics of the data files that are saved to a harddisk are listed under the Files tab in the control pane. Youcan access the file information through a file Propertiesdialog box, which shows similar information for all fileproperties. The available information may differdepending on the file type you are viewing.

You open a Properties dialog box for data items underthe Files tree the same way as items under the Mapstree. (See Managing data properties on page 35 )

About the Bitmap Properties dialogboxThe bitmap Properties dialog box allows you to view andchange several of the attributes for you bitmap files. Youcan review the file history, and add or remove metadata.

(See General tab on page 57 )

General tab

Description:

Lets you change the file name or description appearing inthe Files tree.

Type:

Reports the layer type.

Size on Disk:

Reports the size of the file on disk.

Creation Date:

Indicates when the layer was created.

Last Update:

Shows the last time the raster file was changed.

Raster Size:

Reports the size of the bitmap layer in pixels and lines.

(See History tab on page 57 )

History tab

The History tab allows you to review the processinghistory of the data as a list of algorithms that have beenapplied to the data contained in the image channel.

(See MetaData tab on page 57 )

MetaData tab

The MetaData tab provides a table for working withmetadata names and values associated with the Rasterfile.

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Name:

Shows the name of the metadata file.

Value:

Lets you enter a new value for the metadata file.

Add:

Lets you add records to the MetaData table.

Delete:

Lets you remove records from the MetaData table.

Delete All:

Lets you delete all of the MetaData records from thetable.

About the File Properties dialog boxThe Files Properties dialog box allows you to reviewgeneral file attributes, review the file processing history,manage file metadata, and view and change the fileprojection.

(See General tab on page 58 )

General tab

Description:

Allows you to enter detailed information about a file. Thedescription is shown in the Properties dialog box for thefile.

Type:

Reports the file format.

Size on disk:

Reports the disk size of the file.

Creation date:

Indicates when the file was first created.

Last updated:

Shows when the last edit was made to the file.

Raster Size:

If applicable, reports the size of the raster in pixels andlines.

Interleaving type:

Reports the type of interleaving used in the file.

The following interleave methods are reported:

BAND interleaved:

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Stores all data for one band together. Gives superiorperformance when bands are not accessed continuously.Not supported for files larger than 2 GB.

PIXEL interleaved:

Stores data for all bands at a particular pixel. May givebetter performance when all bands are accessed at thesame time.

FILE interleaved:

Similar to BAND interleaved, but image channel data isstored in external files, one file per band.

Tiled:

Files have image data organized in many square subimages. Tiling provides faster access when a sub-area isextracted for file viewing, and supports compressionformats.

Pathname:

Reports the full path and name of the file.

(See History tab on page 59 )

History tab

The History tab allows you to review the processinghistory of the data as a list of algorithms that have beenapplied to the data contained in the image channel.

(See MetaData tab on page 59 )

MetaData tab

The MetaData tab has a table that displays metadataassociated with the file.

Add:

Lets you add records to the MetaData table.

Delete:

Lets you remove records from the MetaData table.

Delete All:

Lets you delete all of the MetaData records from thetable.

(See Projection tab on page 59 )

Projection tab

The Projection tab allows you to view and change theprojection of your files.

Coordinate System:

Allows you to select a coordinate system for a file.

The available systems are:

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• Pixel• UTM• Long/Lat• Meter• Foot• SPCS• Other

Earth Model:

Opens the Earth Model dialog box, where you canchoose from a list of datum and ellipsoids to define yourcoordinate system.

More:

Opens the UTM, State Plane Zones, or the Projectiondefinition panel if you chose UTM, SPCS, or Other fromthe Coordinate System box.

UTM panel:

Lists the following choices depending on the type ofcoordinate system you chose:

Table 3.

This Projection Opens this panel

UTM Zone and Row

SPCS State Plane Zone

Other Set the ProjectionDefinition

Bounds:

Allows you to show the bounding coordinates of your filein either geocoded (Eastings and Northings) orgeographic (latitude and longitude) units for UTM, SPCS,and other coordinate systems. Bounding coordinates arenot shown for the Pixel option. Long/Lat displays thebounding coordinates in geographic units only. Meter andfoot displays the bounding coordinates in geocoded unitsonly.

Upper left:

The Upper Left boxes show the X, Y coordinates for theupper left corner of the file unless the file contains arotated raster. If the file contains a rotated raster, theUpper Left boxes indicate the coordinates of the first pixelin the file, which is not necessarily the upper left corner.For more information, see About rotated rasters on page34 . Values are in the units of the selected coordinatesystem.

Lower Right:

The Lower Right boxes show the X, Y coordinates for thelower right corner of the file unless the file contains arotated raster. If the file contains a rotated raster, theLower Right boxes indicate the coordinates of the lastpixel in the file, which is not necessarily the lower rightcorner. For more information, see About rotated rasterson page 34 . Values are in the units of the selectedcoordinate system.

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Rotation:

The Rotation boxes indicate the amount the data isrotated. For more information, see About rotated rasterson page 34 .

Pixel Size X:

Reports the horizontal pixel size in the units of theselected coordinate system.

Pixel Size Y:

Reports the vertical pixel size in the units of the selectedcoordinate system.

About the Ground Control Pointsdialog boxThe Vector Properties dialog box allows you to view theproperties and history of vector files. You can alsochange read/write attributes of the vector file, and add orremove metadata.

(See General tab on page 61 )

General tab

You can change information about your Ground ControlPoint (GCP) file and read other file information.

Description:

Lets you change the file name or description appearing inthe Files tree.

Type:

Reports layer type.

Size on disk:

Reports the disk size of the layer.

Creation date:

Reports when the layer was created.

Last updated:

Reports the last time the GCP file was changed.

Number of GCPs:

Reports the number of GCPs in the layer.

(See History tab on page 61 )

History tab

The History tab allows you to review the processinghistory of the data as a list of algorithms that have beenapplied to the data contained in the image channel.

(See MetaData tab on page 62 )

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MetaData tab

The MetaData tab provides a table for working withmetadata names and values associated with thepseudo-color table file.

Name:

The name column shows the name of the metadata file.

Value:

The value column lets you enter a new value for themetadata file.

Add:

Lets you add records to the MetaData table.

Delete:

Lets you remove records from the MetaData table.

Delete All:

Lets you delete all of the MetaData records from thetable.

About the Look-up Table Propertiesdialog boxThe Look-up Table Properties dialog box allows you to

change several of the attributes for look-up table (LUT)files. You can review the file history, and add or removemetadata.

(See General tab on page 62 )

General tab

The General tab allows you to change genericinformation about your file and read other file information.

Description:

Lets you change the file name or description appearing inthe Files tree.

Type:

Reports layer type.

Size on disk:

Reports the disk size of the layer.

Creation date:

Reports when the layer was created.

Last updated:

Reports the last time the LUT file was changed.

(See History tab on page 63 )

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History tab

The History tab allows you to review the processinghistory of the data as a list of algorithms that have beenapplied to the data contained in the table.

(See MetaData tab on page 63 )

MetaData tab

The MetaData tab provides a table for working withmetadata names and values associated with the Look-upTable (LUT) file.

Name:

The name column shows the name of the metadata file.

Value:

The value column lets you enter a new value for themetadata file.

Add:

Lets you add records to the MetaData table.

Delete:

Lets you remove records from the MetaData table.

Delete All:

Lets you delete all of the MetaData records from thetable.

About the Orbit Properties dialog boxThe Orbit Properties dialog box allows you to changeseveral orbit file attributes. You can change the name ofthe file, review the file history, and add or removemetadata.

(See General tab on page 63 )

General tab

Under the General tab, you can change the description ofan orbit file layer and read other file information.

Description:

Lets you change the file name or description appearing inthe Files tree.

Type:

Reports layer type.

Size on Disk:

Reports the size of the layer in bytes.

Creation date:

Reports the layer creation date.

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Last updated:

Reports the last date the file was changed.

(See History tab on page 64 )

History tab

The History tab allows you to review the processinghistory of the data as a list of algorithms that have beenapplied to the data contained in the image channel.

(See MetaData tab on page 64 )

MetaData tab

The MetaData tab provides a table for working withmetadata names and values associated with an orbit file.

Name:

The name column shows the name of the metadata file.

Value:

The value column lets you enter a new value for themetadata file.

Add:

Lets you add records to the MetaData table.

Delete:

Lets you remove records from the MetaData table.

Delete All:

Lets you delete all of the MetaData records from thetable.

About the Pseudo-color tablepropertiesThe Pseudo-color Table Properties dialog box allows youto change several of the attributes for you pseudo-colortable files. You can review the file history, and add orremove metadata.

(See General tab on page 64 )

General tab

You can change information about your file and readother file information.

Description:

Lets you change the file name or description appearing inthe Files tree.

Type:

Reports layer type.

Size on disk:

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Reports the disk size of the layer.

Creation date:

Reports when the layer was created.

Last updated:

Reports the last time the pseudo-color table file waschanged.

(See History tab on page 65 )

History tab

The History tab allows you to review the processinghistory of the data as a list of algorithms that have beenapplied to the data contained in the image channel.

(See MetaData tab on page 65 )

MetaData tab

The MetaData tab provides a table for working withmetadata names and values associated with thepseudo-color table file.

Name:

Shows the name of the metadata file.

Value:

Lets you enter a new value for the metadata file.

Add:

Lets you add records to the MetaData table.

Delete:

Lets you remove records from the MetaData table.

Delete All:

Lets you delete all of the MetaData records from thetable.

About the Raster Properties dialogboxThe Raster Properties dialog box allows you to changeseveral of the attributes for your Raster files. You cangive a raster file read-only status, review the file history,and add or remove metadata.

(See General tab on page 65 )

General tab

You can change generic information about your file andread other file information.

Description:

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Lets you change the file name or description appearing inthe Files tree.

Type:

Reports layer type.

Size on disk:

Reports the size of the layer in bytes.

Creation date:

Reports when the layer was created.

Last updated:

Reports the last time the raster file was changed.

Locking Status:

Gives the raster layer read only status. Read-only Rasterlayers appear in the Files Tree with a red #X# next to theraster icon.

Raster Size:

Reports the size of the raster layer in pixels and lines.

Data Type:

Reports the bit depth of the of the raster layer as one ofthe following data types:

• 8-bit unsigned• 16-bit signed• 16-bit unsigned• 32-bit real

Overviews:

Reports available overviews in the raster file.

(See History tab on page 66 )

History tab

The History tab allows you to review the processinghistory of the data as a list of algorithms that have beenapplied to the data contained in the image channel.

(See MetaData tab on page 66 )

MetaData tab

The MetaData tab provides a table for working withmetadata names and values associated with the Rasterfile.

Name:

Shows the name of the metadata file.

Value:

Lets you enter a new value for the metadata file.

Add:

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Lets you add records to the MetaData table.

Delete:

Lets you remove records from the MetaData table.

Delete All:

Lets you delete all of the MetaData records from thetable.

About the Signatures Propertiesdialog boxThe Signatures Properties dialog box allows you tochange several of the attributes for the pseudo-colortable files. You can review the file history, and add orremove metadata.

(See General tab on page 67 )

General tab

Under the General tab you can change information aboutyour file and read other file information.

Description:

Lets you change the file name or description appearing inthe Files tree.

Type:

Reports layer type.

Size on disk:

Reports the disk size of the layer.

Creation date:

Reports when the layer was created.

Last updated:

Reports the last time the Signatures file was changed.

(See History tab on page 67 )

History tab

The History tab allows you to review the processinghistory of the data as a list of algorithms that have beenapplied to the data contained in the image channel.

(See MetaData tab on page 67 )

MetaData tab

The MetaData tab provides a table for working withmetadata names and values associated with thepseudo-color table file.

Name:

Shows the name of the metadata file.

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Value:

Lets you enter a new value for the metadata file.

Add:

Lets you add records to the MetaData table.

Delete:

Lets you remove records from the MetaData table.

Delete All:

Lets you delete all of the MetaData records from thetable.

About the Text Properties dialog boxThe Text Properties dialog box allows you to changeseveral text file attributes. You can change the name ofthe file, review the file history, and add or removemetadata.

(See General tab on page 68 )

General tab

You can change the description of your file and readother file information.

Description:

Lets you change the file name or description appearing inthe Files tree.

Type:

Reports layer type.

Size on Disk:

Reports the size of the layer in bytes.

Creation date:

Reports the layer creation date.

Last updated:

Reports the last date the file was changed.

(See History tab on page 68 )

History tab

The History tab allows you to review the processinghistory of the data as a list of algorithms that have beenapplied to the data contained in the image channel.

(See MetaData tab on page 68 )

MetaData tab

The MetaData tab provides a table for working withmetadata names and values associated with a text file.

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Name:

Shows the name of the metadata file.

Value:

Lets you enter a new value for the metadata file.

Add:

Lets you add records to the MetaData table.

Delete:

Lets you remove records from the MetaData table.

Delete All:

Lets you delete all of the MetaData records from thetable.

About the Vector Properties dialogboxThe Vector Properties dialog box allows you to view theproperties and history of vector files. You can alsochange read/write attributes of the vector file, and add orremove metadata.

(See General tab on page 69 )

General tab

Description:

Lets you change the file description appearing in the Filestree.

Name:

Lets you change the name of the vector layer appearingin the Files tree.

Type:

Reports layer type.

Size on disk:

Reports the disk size of the layer.

Creation date:

Indicates when the vector file layer was created.

Last updated:

Shows the last time the vector file layer was changed.

Data Type:

Reports the type of vector data.

Shape Count:

Reports the number of shapes in the vector file layer.

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(See History tab on page 70 )

History tab

The History tab allows you to review the processinghistory of the data as a list of algorithms that have beenapplied to the data contained in the image channel.

(See MetaData tab on page 70 )

MetaData tab

The MetaData tab provides a table for working withmetadata names and values associated with the vectorfile.

Name:

Shows the name of the metadata file.

Value:

Lets you enter a new value for the metadata file.

Add:

Lets you add records to the MetaData table.

Delete:

Lets you remove records from the MetaData table.

Delete All:

Lets you delete all of the MetaData records from thetable.

(See Projection tab on page 70 )

Projection tab

The Projection tab allows you to change the vectorprojection and select an Earth model and a UTM zone forthe vector layer.

Projection:

Allows you to choose a different projection for the vectorfile layer.

You can choose the following projections from thelist box:

• Pixel• UTM - Opens the UTM Zones dialog box.• Lat/Long - Makes the Earth Model button available

and reports the current Datum and Ellipsoid.• Meter - Makes the Earth Model button available and

reports the current Datum and Ellipsoid.• Foot - Makes the Earth Model button available and

reports the current Datum and Ellipsoid.• SPCS - Makes the Earth Model button available,

reports the current Datum and Ellipsoid, and opensthe State Plane Zones dialog box.

• Other - Makes the Earth Model button available,reports the current Datum and Ellipsoid, and opensthe Other Projections dialog box. (See About theOther Projections dialog box on page 71 ).

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Earth Model:

Opens the Earth Model dialog box.

More:

Opens the State Plane dialog box.

About the Other Projections dialog box

The Other Projections dialog box lets you choose aprojection other than Pixel, UTM, Lat/Long, Meter, Foot,and SPCS. The Other Projections dialog box is availablewhen you choose Other from the projections list underthe Projection tab in any Properties dialog box. (SeeReprojecting files on page 134 )

Color mapping and image profilesFocus lets you map individual color elements andcombinations of red, green, and blue (RGB) colorelements to the channels in data with the RGB Mappingdialog box. You can also generate an image profile graphand a numeric table of profile values for your activeimages. The Profile Table and Profile Graph dialog boxesare used together when working with profiles and theyallow you to print and save information.

About the RGB Mapping dialog box

The RGB Mapping dialog box shows the color content ofred, green, and blue data in a multi-spectral data file

table. The RGB Mapping dialog box lets you change ormap the channel data to a color element and show thechanges in the view pane.

Target Map Layer:

Reports the source file that contains the image layerslisted in the RGB Mapping dialog box.

Red:

Lists the channels available for red mapping.

Green:

Lists the channels available for green mapping.

Blue:

Lists the channels available for blue mapping.

Image Layers:

Lists the data layers in the target Map layer that can bemapped to red, green, and blue color elements.

1. Select an image layer in the Maps tree.2. From the Layer menu, click RGB Mapper.3. Click in the Red, Green, and Blue columns next to

the image channel to which you want to apply thatfilter.

You can assign only one color to a channel. Theimage in the view pane changes according to thenew mapping.

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4. Click Close.

Note: Changing band combinations cancelsenhancements you have applied. To maintain anenhancement, you must enhance the image again.Remove an applied enhancement and then re-apply it.

Creating an image profile

Focus lets you generate a spectral plot and a table ofnumeric values across an overlaid vector that showsimage information related to the RGB input channels. Theresulting image profile gives a cross section of the pixelvalues under the vector. Focus automatically generates atable of pixel values for the vector. Pixel values in theprofile table are across three image planes. You can savethe table values as a text file and you can save and printthe profile graph.

Vector Profiles:

If a vector is not open, a line is automatically generatedand used to calculate the profile. You may want to createa vector profile under a specific area of your image orselect an existing vector for the profile. You can modifythe profile or draw a new one.

To create an automatic image profile:

1. With a raster file open, do one of the following:• Click Layer and then click Profile.• Right-click a raster layer in the Maps tree and

click Profile.

Focus automatically adds a new vector layer to theMaps tree and a new vector to the view pane tocalculate the vector profile. The Profile graph andtable also appear.

To create a new image profile:

1. With a raster file open, open a vector segment oradd a new vector layer and draw a vector using theVector Editing tools.

2. Select the image layer and click Layer and thenclick Profile.

You can also right-click a raster layer in the Mapstree and click Profile.

Focus automatically adds a new vector layer to theMaps tree and a new vector to the view pane tocalculate the vector profile. The Profile graph andtable also open.

To display the image profile of the vector from thevector layer, select the vector layer in the Map tree.

3. Click the Vector Editing button.4. Click the vector for which you want to make a

profile.

About the Profile Table dialog box

The Profile Table dialog box lists the RGB values, X/Ypositions, and scaled distances for each pixel included inthe overlaid vector segment. Pixels are incrementedautomatically and several statistical and graphical

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adjustments can be made.

Sample:

Reports an automatic increment for each pixel along thevector. Pixel 1 is the first pixel at the vector point of origin.

Channel 1:

Lists all of the pixel values for the color you have mappedto channel 1.

Channel 2:

Lists all of the pixel values for the color you have mappedto channel 2.

Channel 3:

Lists all of the pixel values for the color you have mappedto channel 3.

Pixel/Line:

Lists a pixel and line coordinate location for each pixelalong the vector.

X position:

Lists the X coordinate for each pixel along the vector.

Y position:

Lists the Y coordinate for each pixel along the vector.

Distance:

Lists the scale distance for each pixel relative to theimage scale. Distances are expressed in units ofmeasure corresponding to the image in the view pane.

Close:

Closes the Profile Table dialog box.

Graph:

Brings the Profile Graph dialog box to the front of yourdesktop.

Statistics:

Opens the Profile Statistics dialog box. (See below)

Save:

Opens the Save Table dialog box.

Options:

Opens the Profile Options dialog box. (See About theProfile Options dialog box on page 74 )

About the Profile Statistics Dialog Box:

The Profile Statistics dialog box is opened from the

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Profile Table dialog box and shows the statistics for eachchannel in a selected layer.

The following statistics are calculated automatically:

• Sample Min• Sample Max• Sample Avg• Weighted Avg

Statistics are a summary for the sample gray valuesalong the profile. The weighted average is the mostaccurate measure of central tendency among the samplepoints. The weight of a sample gray value is the ratio ofthe length of a sample interval over the total distance ofall the sample intervals.

About the Profile Options dialog box

The Profile options dialog box allows you to makechanges to the profile graph and the profile table. Youcan simultaneously change information reported in theProfile Table and Profile Graph dialog boxes. You openthe Profile Options dialog box with the Options button inthe Profile Table dialog box.

Color:

Reports the colors used to plot the channels in the ProfileGraph. Clicking in a Color column cell opens the LineColor dialog box.

Visible:

Reports the channels shown as plot lines in the ProfileGraph and as channel columns in the Profile Table.Enabling a Visible column cell shows the correspondingline and column in the Profile Graph and the Profile Tabledialog boxes.

Current Channel:

Lets you change the focus of the Profile Graph to thechannel you want.

Profile View:

Lets you choose between a graph showing grayscalevalues along either a georeferenced or a sample pointscale.

Georeferenced:

Switches the X axis of the graph to the linear scale viewof your image.

Sample Points:

Switches the X axis of the graph to the pixel number viewof the vector profile.

1. In the Profile Options dialog box, click a color chipfor the corresponding channel.

2. In the Color Panel dialog box, make any changes tothe basic color, color continuum, or intensity.

3. Click OK.

About the Profile Graph dialog box

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The Profile Graph dialog box lets you view the graphplotted from the information corresponding to the overlaidvector and the values listed in the Profile Table dialogbox. You can zoom in the graph to look at a segment ofthe plot.

Sample Profile of Selected Channels:

Contains the graph with a profile of the channels youhave chosen in the Visible column of the Profile Optionsdialog box. (See About the Profile Options dialog box onpage 74 )

The vector profile is interpreted from left to right;however, if the end points of the vector occupy the sameX position, the profile is interpreted from the top down.With closed shapes, the profile is interpreted in aclockwise direction from the start/end node.

Gray-value changes are shown as a function of distancealong the vector. The graph gives a profile of the imagelayer and the distance along the vector on the X axis.

Gray Values:

Shows the input channels plotted with the gray valuesalong the Y axis of the graph.

Sample Points:

When you choose the Sample Points option in the ProfileOptions panel, an 8-bit RGB image layer shows a rangealong the X axis of 0 to 255 and represents the 256possible gray-level values for each pixel of the red,

green, and blue input channels. Both 16-bit and 32-bitreal raster data can be graphed showing the 16-bit and32-bit range of values.

Distance:

When you choose the Georeferenced option in the ProfileOptions dialog box, the X axis is measured in meters andrepresents the distance between the end points of thevector. The range of the X axis depends on the length ofthe vector and the scale of the area or the grounddistance covered by the image.

Mensuration Bars:

Reports the position of the measuration bars in pixels orin scale distance along the vector, depending on theProfile View option, selected in the Profile Options dialogbox.

You can move the measuration bars on the graph bydragging the left side of the graph to the right.

Left Bar X:

Reports the X position of the left measuration bar.

Left Bar Y:

Reports the Y position of the left measuration bar.

Right Bar X:

Reports the X position of the right measuration bar.

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Right Bar Y:

Reports the Y position of the right measuration bar.

Difference X:

Reports the difference between the left and rightmeasuration bars along the X axis of the graph.

Difference Y:

Reports the difference between the left and rightmeasuration bars along the Y axis of the graph.

Close:

Closes the Profile Graph dialog box.

Show All:

Restores the graph to a full view after the graph has beenzoomed.

Graph Controls:

Opens the Graph Controls dialog box.

About the Graph Controls dialog box

The Graph Controls dialog box allows you to change theviewable range for both the X and Y axes, export the plotto a graphic file, change the background color for the plot,and print the plot.

X View Range:

Allows you to set the minimum and maximum ranges ofthe X axis of the profile graph.

Min:

Allows you to enter a minimum range for the X axis of theprofile graph.

Max:

Allows you to enter a maximum range for the X axis ofthe profile graph.

Y View Range:

Allows you to set the minimum and maximum ranges ofthe Y axis of the profile graph.

Min:

Allows you to enter a minimum range for the Y axis of theprofile graph.

Max:

Allows you to enter a maximum range for the Y axis ofthe profile graph.

Export:

Allows you to choose a file and a format for exporting

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your graph.

File:

Opens a File Selector dialog box, where you can choosea target file for exporting your graph.

File Format:

Lets you choose a file format for exporting your graph.

Options:

Lets you show a legend on your graph, lock the aspectratio of the X and Y axes, and change the backgroundcolor of the graph.

Show Legend:

Shows or hides the legend on the Profile Graph dialogbox. The legend is printed with the graph when thisoption is checked.

Fix Aspect Ratio:

Locks the aspect ratio of the X and Y axes of the graph.

Background:

Lets you change the background color of the graph.

Using the graph controls

The Graph Controls allow you to edit the X and Y axis ofa profile. You can also change the graph colors. You cancontrol the range with the Min. and Max arrows. The FixAspect Ratio option holds the X and Y axis to the originalrelationship.

The range varies depending on the ground distancecovered by the image and the length of the vector. Therange default value depends on the image bit depth (forexample, 8-bit, 16-bit, and so on).

At the bottom of the Profile Graph dialog box, click GraphControls. You can also right-click in the profile and clickGraph Controls.

Range Controls:

The range of the graph is controlled with the Min. andMax arrows. The Fix Aspect Ratio option holds the X andY-axis to the original relationship. To adjust the X and Yaxis independently, make sure this option is disabled.You can return to the original values by clicking Show Allat the bottom of the Profile Graph dialog box.

The range varies depending on the ground distancecovered by the image and the length of the vector.

You can also interactively draw a box on your vectorprofile graph to zoom into an area of interest on the graphby dragging a box around the area of the graph intowhich you want to zoom. You can zoom back out to theoriginal X and Y range by clicking Show All.

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Legend and Color Controls:

You can show he legend for the color channels byenabling the Show Legend check box.

• Select a color from the Background list.

Exporting profiles

To export your profile information, you can:

• Save your graph as a PCIDSK (.pix), TIFF (.tif),bitmap (.bmp), or PostScript (.ps) file through theGraph Controls dialog box.

• Print the profile graph by clicking Print at the bottomof the Graph Controls dialog box.

• Save your profile table to a text file through theProfile Table dialog box. This text file can beimported to any spreadsheet for editing or analysis.

You can change the file format before selecting theoutput file.

1. In the Export area of the Profile Graph dialog box,select a format from the Format list box.

2. Click File.3. In the File Selector dialog box, navigate to and

select a file.4. Click Save.5. In the Profile Graph dialog box, click Export.

Printing your graph without showing themensuration bars

1. From the Profile Table dialog box, click Options.

2. In the Profile Options dialog box, click the field withan X in the Current Channel column.

3. Click Close.4. In the Profile Table dialog box, click Graph.5. In the Profile Graph dialog box, click Graph

Controls.6. In the Graph Controls dialog box, click Print.7. In the Print dialog box, click OK.

Using the View toolsFocus offers several tools to view, create, and savecustom views of specific regions in your image data. Thissection covers the methods and tools for focusing onspecific parts of an image.

Using the Zoom window

The Zoom Window lets you see a linked copy of yourimage data in a separate viewer. You can zoom theimages independently, using one image to locatefeatures and the other to zoom in for a closer look. Youopen the Zoom Window from the View menu. When youclick the Lock command, you can move the cursor in theview pane without changing the image in the ZoomWindow.

Using a Clone view

You can use the Clone View feature for several tasks.For example, if you want to compare classified imageswith reference images or if you want to analysemulti-temporal imagery, you can use Clone View to openseveral independently enhanced versions of the same

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image to help discriminate certain features.

The clone view command opens a second window for thecurrent project. A copy of the project opens in the Mapsand Files trees in the view pane.

Clone views are independent of the source view showingin the original project window. Changes made to theproject are not reflected in the cloned window. Once aClone View is open, a new image can be opened in theproject window with no effect on the cloned view.

Chaining clone views

When you have an open Clone View, you can use theChained Window command to have the cursor position inthe Focus view pane automatically control the cursorposition in the Clone view, vice versa, or have bothcursors affect each other.

1. From the View menu of the project window, clickClone View.

2. If you want the cursor in the Focus view pane tofollow the cursor in the Clone view, click theChained Window button on the Focus toolbar.

3. If you want the cursor in the Clone view to follow thecursor in the Focus view pane, click the ChainedWindow button on the Clone view toolbar.

Zooming using the Overview window

If you have a very large image file open or if your imageis zoomed in, you can pan around the image in the view

pane. There are two ways to pan around images: you canclick the Pan button in the Focus toolbar or you can usethe bounding outline in the overview window. The extentsfor the overview window are based on the extents of alldata loaded in the main viewer regardless of what datatypes you set to be shown.

When you open image data in Focus, the overviewwindow shows a smaller version of the image in the viewpane. The overview window has a bounding outline thatyou can use to control the view in the view pane. You canclick the bounding outline to pan around the image in theview pane and you can resize the bounding outline tozoom the image in the view pane.

1. In the overview window, pointer to a corner of thebounding box.

2. Drag the bounding box to a new size.

Dragging the box in the overview window moves theimage in the view pane without changing the zoom level.

Creating named regions

You can create a custom view of your map or image withthe Named Regions tool. When you create a namedregion, the viewer can move to it in the view pane.

New named regions are defined by upper-left andlower-right corner coordinates. You can define theboundaries of a new region by using either the zoomtools on the Focus toolbar or by using the advancedfeatures of the Named Regions dialog box. You can save

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your named regions when you save the current project. Ifyou add, remove, or edit the name of a Map or Area inthe Maps tree, the information is updated in the NamedRegions tree.

The Named Regions dialog box has a tree similar to theone in the control pane. In the Named Regions tree, onlythe named regions are listed. New named regions areshown by either an Area-named regions icon or aMap-named regions icon.

1. In the Maps tree, choose an Area or a Map fordefining your named region.

2. Use any of the zoom tools, including the boundingoutline in the overview window, to define yourregion.

3. From the View menu, click Named Regions.4. In the Named Regions dialog box, click the +

button.5. Type a name of the selected region in the Named

Region 1 box.6. Click OK.

Removing named regions

1. From the View menu, click Named Regions.2. In the Named Regions dialog box, select a region.3. Click the - button.

You can also right-click a named region in the NamedRegions tree and click Remove.

You can define a named region using coordinateinformation and you can edit your coordinates. By default,

the advanced features show raster coordinates for theimage data open in the view pane. You can describe thebounds of your named region in Raster, Geocoded,Geographic, or MGRS units.

Creating named regions using coordinates

1. In the Named Regions dialog box, click Advanced.2. Select a reference system from the Bounds list

box.3. Type the coordinates of your named region in the

appropriate boxes, based on the selected referencesystem.

4. Click the + button.5. Type a name of the selected region in the Named

Region 1 box.6. Click OK.

Panning an image

There are many ways to visualize image data in the viewpane. This section covers all of the various methods andtools for looking at the parts of your image data that youwant.

Panning

When you have a very large image file open or whenyour image is zoomed in, you can pan around the imagein the view pane. There are two ways to pan aroundimages: you can click the Pan tool in the Focus toolbar oryou can use the bounding outline in the overview window.

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1. On the Focus toolbar, click the Pan button.2. Drag the image where you want to go.

You can also scroll an image using the standard scrollbars along the horizontal and vertical edges of the viewpane.

Zooming

You can zoom in or out to a particular location even whenyou have multiple images opened.

Zooming an image with zoom tools

1. In the view pane, click a location or feature in theimage.

2. On the Focus toolbar, click the Zoom In button.

The image is enlarged by a factor of 2.

To zoom out, click the Zoom Out button.

Viewing a 1:1 image resolution

1. In the view pane, click the image.2. On the Zoom toolbar, click the Zoom to 1:1 Image

Resolution button.

Note: When more than one image is open, the zoomtools apply to all images in the view pane.

Using a layout gridThe Layout Grid can use dots or lines to help you drawand lay out items in the view pane. You can align orposition any map element relative to the grid. There aregrid properties for Show Grid and Snap to Grid that canbe turned on or off. You cannot print a Layout Grid.

There are two options for displaying the grid: the firstoption shows the grid as dots; the second option showsthe grid as lines. The index for the grid is displayed as across or wider line. All map objects can snap to the grid.

• For areas, the handles of the bounding box areused for snapping. The closest handle to the cursorclick position snaps to a grid point.

• For Points, either text or symbols, the insertion pointsnaps to the grid point.

• For shapes, snapping is the same as snapping anarea.

A grid point is the intersection of a horizontal and avertical grid line. When the grid is displayed as dots, eachdot is placed at a grid line intersection point.

Grid spacing

The Grid Spacing section sets the spacing for both thedots and lines.

Horizontal:

The default spacing is 1.00 Millimetre

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Vertical:

The default spacing is 1.00 Millimetre.

The unit options for spacing are in standard paper units:millimetre, inch, point, and pica.

The Keep Equal option forces the grid spacing to beequal in both directions. You can disable the option if youwant different horizontal and vertical spacing. This optionis checked by default.

Index spacing

Index spacing is based on your grid spacing.

Horizontal:

Spacing for the index is in grid units. The default is 10.Every tenth dot or line is an index dot or line.

Vertical:

Spacing for the index grid is also in grid units. The defaultis 10. Every tenth dot or line is an index dot or line.

The Keep Equal option forces the index spacing to beequal in both directions. You can disable this option if youwant different horizontal and vertical spacing.

Show Grid:

Switches the grid off or on in the view pane. Enable this

option to show the grid.

Snap to Grid:

Switches the grid snapping behavior off or on. Enable thecheck box to make map elements snap to the grid.

1. From the View menu, click Layout Grid Setup.2. In the Layout Grid Setup dialog box, click either

the Dots or the Lines option.3. Select a color for your grid from the Color list.4. Select grid and index spacing by entering values in

the Grid Spacing and Index Spacing spin boxes.

If you want to display the grid in the view pane,enable the Show grid check box.

If you want new objects in the view pane to snap toyour grid, enable the Snap to grid check box.

5. Click OK.

Visualizing your dataFocus provides a set of active visualization tools that canautomate your work. The visualization tools are ideal forwork requiring change detection between imagesrecorded at different times. You can also use thevisualization tools to ensure accuracy in yourcartographic projects when you use imagery as abackground layer to update vector or bitmap data.

Enhancing images

Images can be processed at several levels, from

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standard enhancements that filter images to fullycustomized enhancements using look-up tables andhistograms. Unenhanced image files are often impossibleto understand visually when they are opened in an imageviewer. Enhancements make imagery clearer and easierto interpret. When you open an image file, it isautomatically enhanced in the view pane. You canchange the default enhancement. (See Changing adefault enhancement on page 244 )

Using the Attribute Manager

The Attribute Manager produces a table showing all pixelvalues for raster attributes. You can select vectors,search for segments, and locate records. You can alsoedit vector attribute records and fields. (See Performingtasks in the Attribute Manager on page 304 )

• From the Maps or Files tree, right-click a layer andclick Attribute Manager.

Importing XML metadata using theMETAIN algorithm

When you import data, you can also import imagemetadata from an XML-format text file and examine bothglobal and band-specific metadata during the operation.Importing metadata is important when working withhyperspectral data. Many hyperspectral data sets includeadditional information about the mission and the sensorused to acquire the data.

The first step in a project is to import data. If the data filesare not in .pix format, you must obtain the data format. Ifthe data is partitioned into different files, importing it in.pix format may require separate imports, transferringlayers from one file into the final output file, or a singleimport.

Mission and sensor metadata must be attached to theimage data to make processing and analyzing it moreefficient. The metadata must be formatted as an XMLdocument in a text file. Metadata is read into the .pix filecontaining the image data as a metadata segment usingthe METAIN program. This can be opened through EASIor the Algorithm Librarian in Focus. Conversely, theMETAOUT program will read the information in themetadata segment and export it as an XML document.

The algorithm METAIN reads image metadata from anXML document that is stored in a text file, reformat thedata, and stores them in a GDB file. The required formatfor an XML file can be found in the documentPCIImageMetadata.xsd in the $PCIHOME\etc folder.

The XML document file must be in the same folder andhave the same base name as the GDB file. The XMLdocument file must have an .xml file name extension.

Global Metadata

Many global metadata items are optional and can beabsent from the data files you are working with. Thefollowing table is a list of both required and optionalmetadata items.

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Table 4.

Required Optional

Text data set descriptions Name of the sensor model

Number of image bands Name of the sensor type

Number and sequence ofradiometrictransformations stored asband-specific metadata.

Location of imageacquisition

Time of image acquisition

Heading of the platform

Fore-aft sensor tilt relativeto gravity vector

Total sensor field-of-view

Band-specific Metadata

Some band-specific metadata is also optional. Thefollowing table shows a list of both required and optionalband-specific metadata items

Table 5.

Required Band-SpecificMetadata Items

Optional Band-SpecificMetadata Items

Band ID number Band quality

The number of the filechannel that stores theband

Radiometric transformationsequence

Required Band-SpecificMetadata Items

Optional Band-SpecificMetadata Items

Response profile

The METAIN is in the Algorithm Librarian. The AlgorithmLibrarian lists algorithms in a tree of file folders. Thefolders are organized by algorithm category. Somecategory folders contain a sub-category of algorithms.

1. From the Tools menu, click Algorithm Librarian.2. In the Select Algorithm dialog box, expand the

Analysis folder.3. Expand the Hyperspectral Analysis folder.4. Double-click the METAIN algorithm.5. In the METAIN Module Control Panel, click the

Input Params 1 tab and click Browse.6. Navigate to the file you want, select it, and click

Open.7. In the METAIN Module Control Panel, click Run.

Opening an image data set

1. In the Files tree, right-click anywhere in the whitearea and click Add.

2. In the File Selector dialog box, locate and select adata file, and click Open.

Viewing global metadata

1. In the Files tree, right-click the file you want to viewand click Properties.

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2. In the Properties dialog box, click the MetaDatatab.

The global metadata is listed.

Viewing band-specific metadata

1. In the Files tree, expand the list of raster layers inyour file.

2. Right-click a raster layer and click Properties.3. In the Properties dialog box, click the MetaData

tab.

The band-specific Metadata is listed.

Enabling and disabling panes

The status bar contains several panes that communicateinformation from the viewer. Panes identified by a checkmark are enabled.

1. On the status bar, click the down arrow on the left.2. Select the pane of your choice:

• Messages: displays brief text messages tocommunicate ScreenTips, explanations, andinstructions.

• Progress: displays a progress indicator thatshows how much of a process is completed.

• ZoomScale: displays the scale at the zoomlevel used in the viewer.

• ZoomImagePixel: displays the magnificationfactor used in the viewer.

• CursorPosition: displays the coordinate ofthe cursor in the viewer. You can also select

the unit for the coordinate#s display.• SelectionValue: displays the pixel value at the

cursor.

Changing the units for the cursor position

1. On the status bar, click the down arrow on theCursorPosition bar.

2. Select the unit of your choice:• Paper: displays the coordinates in millimeters.• Raster: displays the coordinates in image

pixels and lines measured from the upper leftcorner of the image.

• Geocoded: displays the coordinates inEasting and Northing values.

• Geographic: displays the coordinates inLongitude and Latitude values.

• MGRS: displays the coordinates using theMilitary Grid Reference System.

• Screen: displays the coordinates in screenpixels measured from the upper left corner ofthe viewer.

Using the Visualization toolsThe visualization tools let you view and compare multipleimage layers simultaneously. You can automaticallybrowse a set of image layers or blend different images tosee specific parts of one image through another. Thetools can also be used with any of the enhancements orfilters.

Some visualization modes have different datarequirements. For example, the Flicker, Blend, and Swipe

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tools require files with more than one image layer to bevisible. The Loop tool requires a minimum of three layersto be open and the Cycle tool requires either an RGB or ahyperspectral file. The following screens provideinformation for using each of the visualization modes thatare available. (See About the Visualization Tools dialogbox on page 86 )

About the Visualization Tools dialogboxThe Visualization Tools dialog box provides controls forthe Flicker, Swipe, Blend, Loop, and Cycle tools. Thecontrols for each visualization mode are separated by atab at the top of the panel. You can set frame rates,image positions, mode orientation, and you can start andstop each visualization operation with the controls underthe corresponding panel tab.

For more information, see the following:

• Using the Flicker tool on page 86• Using the Swipe tool on page 86• Using the Blend tool on page 87• Using the Loop tool on page 88• Using the Cycle tool on page 89• Using the Band Cycling tool on page 90

Using the Flicker tool

The Flicker tab controls the flicker visualization mode.

Speed [frame/sec]:

Allows you to change the frame rate of the flicker action.

Actual:

Reports the actual frame rate of the flicker when it isrunning.

Control:

Allows you to start and stop automatic flicker and tomanually cycle through the flicker visualization mode.

Current Top Layer:

Reports the name of the active layer in the view pane.

Using Flicker:

Switches your view between two layers within the sameMap. When you select any two layers in the Maps tree,the associated images flicker from the front to the back ofthe view pane, making it easier to see subtle differencesbetween them.

1. From the View menu, click Visualization Tools.2. In the Visualization Tools dialog box, click the

Flicker tab.3. In the Maps tree, select two layers by holding the

Ctrl key while clicking the layers you want to view.4. Type a value for the flicker rate in the Speed

[frame/sec] box.5. Click the Start Automatic Flicker button.

Using the Swipe tool

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The Swipe tab controls the swipe visualization mode.

Horizontal:

Changes the swipe to a horizontal direction.

Vertical:

Changes the swipe to a vertical direction.

Position [%]:

Allows you to step through a swipe cycle while reportingthe portion of the cycle as a percentage of the swipedimages.

Auto Mode

The Auto Mode area lets you set and operate theautomatic swipe features.

Speed [frame/second]:

Sets the frame rate of the image swipe.

Actual:

Reports the actual frame rate for the swipe operation.

Control:

Allows you to start and stop the automatic image swiping.

Step Size [%]:

Lets you adjust the size of the swiped portion of theimage in each step.

Using Swipe:

Displays a file in increments across another; at any pointduring the process, you can look at a specific percentageof the swiped file.

1. In the Visualization Tools dialog box, click theSwipe tab.

2. Click one of the following options:

Horizontal: changes the swipe to a horizontaldirection.

Vertical: changes the swipe to a vertical direction.

3. Type a value for the size of the swipe percentage inthe Position box.

4. Type a value for the flicker rate in the Speed[frame/sec] box.

5. Type a value for the step size in the Step size box.6. Click the Start Automatic Swipe button.

The swipe operation continues until you click theStop Automatic swipe button.

Using the Blend tool

The Blend tab controls the blend visualization mode.

Position [%]:

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Allows you to step through a blend cycle while reportingthe portion of the cycle as a percentage of the blendedimages.

Auto Mode

The Auto Mode area lets you set and operate theautomatic blend features.

Speed [frame/second]:

Sets the frame rate of the image blend.

Actual:

Reports the actual frame rate for the blend operation.

Control:

Allows you to start and stop the automatic imageblending.

Step Size [%]:

Lets you adjust the size of the blended portion of theimage in each step.

Using Blend:

Merges two layers together at a specified rate. Thetransition from one view to another helps you seechanges between layers.

1. In the Visualization Tools dialog box, click the

Blend tab.2. Type a value for the position of the blend in the

Position box.3. Type a value for the flicker rate in the Speed

[frame/sec] box.4. Type a value for the step size in the Step size box.5. Click the Start Automatic Blend button.

The blend operation continues until you click theStop Automatic Blend button.

Using the Loop tool

The Loop tab controls the loop visualization mode.

Forward:

Cycles the data forward from the lowest to the highestpriority.

Backward:

Cycles the data backward from the highest to the lowestpriority.

Continuous Loop:

Cycles the data continuously according to the directionoption you choose.

Speed [frame/second]:

Sets the frame rate of the image blend.

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Actual:

Reports the actual frame rate for the blend operation.

Control:

Allows you to start and stop the automatic imageblending.

Current Top Layer:

Reports the name of the active layer in the view pane.

Using Loop:

Loop mode is a multi-view tool that extends automatic filecomparison capabilities to include three or more files.You must have at least three layers open to enable theLoop tab. To use the Loop tool, click the Loop tab.Specify the desired flicker speed (frames/sec) and clickthe Start Automatic Loop button.

You can specify a forward (starting with the first file andending with the last file in the maps tree) or backwardloop by clicking in the Forward or Backward options. Ifthe Continuous Loop option is enabled the files willcontinually flicker. If the Continuous Loop option isdisabled the files will loop only once.

Using the Cycle tool

The Cycle tab controls the cycle visualization mode.

Color Channel

The Color Channel section provides options for viewingchannels and channel combinations you want to cycle.

Red:

Lets you cycle only the red channels in your data file.

Green:

Lets you cycle only the green channels in your data file.

Blue:

Lets you cycle only the blue channels in your data file.

File:

Reports the color channel source data file.

Cycle Through All Files:

Lets you cycle through all of the color channels in yourimage data.

Channel:

Changes the file report to show the channel currentlybeing cycled.

Display Ranges:

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Lets you enter a range or series of channel ranges to becycled in the view pane.

Forward:

Cycles your data forward from the lowest to the highestpriority.

Backward:

Cycles your data backward from the highest to the lowestpriority.

Speed [frame/second]:

Sets the frame rate of the image cycle.

Actual:

Reports the actual frame rate for the cycle operation

Control:

Allows you to start and stop the automatic image cycling.

Current Top Layer:

Reports the name of the active layer in the view pane.

Using Cycle:

Cycle mode displays image data through the colorcomponent you specify. The color that image channels

cycle through is set using the red, green, or blue colorchannel options. You can select image channels to usewith the Display Ranges text box.You can also specifywhether the image layers will be cycled through the colorcomponent forward, starting with the first image channelyou specify or backward, starting with the last imagechannel specified. (See Using the Band Cycling tool onpage 90 )

Using the Band Cycling tool

The cycle tool can be used with hyperspectral data toview different channel and wavelength ranges in aspecified color component to create new colorcomposites. You can cycle two color channels in the viewpane and control the speed and range of channels thatyou are cycling through.

1. With image data open, click View and then clickVisualization Tools.

2. In the Visualization Tools dialog box, click theCycle tab.

3. Click a Color Channel option. The color youchoose is the layer through which the hyperspectralchannels cycle.

4. Enable a range of either channels or wavelengths tocycle using a selected color channel.

To select a range of wavelengths, there must beassociated metadata for each channel in thehyperspectral file. (See Importing XML metadatausing the METAIN algorithm on page 83 )

5. Enter a display range in the Display range box.

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More than one channel or wavelength range can beentered. Ranges are shown using a dash betweenthe beginning and end of the range; multiple rangesare separated by a comma.

For example 1-5, 15-20, 30-35 are valid entries forchannel display ranges.

6. Select a cycle direction by enabling either theForward or Backward option.

If forward cycling is selected, the channel cyclingorder is 1-5, 15-20, and then 30-35; if reversecycling is selected, the channel cycling order is35-30, 20-15, and then 5-1.

7. Click the Start Automatic Cycle button.

The cycling continues until you click StopAutomatic Cycle.

The number at the bottom of the Visualization Toolsdialog box represents the displayed channel. If you donot click Apply prior to clicking Close, the dialog boxcloses and the RGB layer reverts back to the originalcombination. Clicking Apply updates the RGB layer toreflect the new channel in the identified element and thelayer name is updated. The following is a list of BandCycling dialog box controls with details about what theydo.

Select Color Channel:

Lets you specify the color of the view channel. Thechannels in the two colors that are not selected will not

change. Next to the color is the file of the channelcurrently mapped to the color. If all the colors aremapped to a channel in the same file, these labels willnot appear.

Cycle through all files:

Enable this check box when the active RGB layercontains channels from multiple files and you want tocycle through all the channels in all files mapped to theRGB layer. This function is only available when the colorsof the active RGB layer are mapped to more than onefile.

Display Range:

You can specify ranges of channels to cycle through aspecified color component and you can specify either thechannel number or wavelength. The system cyclesthrough all available channels by default.

Speed & Actual:

Sets the channel cycle speed through the color element.The actual speed at which the channels are being cycledis also the speed they are displayed.

Forward & Backward:

Allows you to set the direction of cycling, either forward orbackward.

Control:

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Stop and play buttons activate the cycling. You can alsostep through the channels one channel at a time. Thedirection of the stepping is set by the Forward andBackward options selections.

Current Channel:

The current channel being cycled through the identifiedcolor element is displayed. When you presses the stopbutton, the last channel cycled through is displayed.

Opening the Thumbnails viewer

You must have a file open before the Thumbnails viewercommands are available from both the Tools menu andthe shortcut menu. A new map and area are added whenyou select layers from the Thumbnails viewer.

The Thumbnails viewer works for multispectral andhyperspectral data, but displays raster layers only. If a filecontains no channels, the Thumbnails command is notavailable. You can view images across several spectralbands in a tiled rectangular array. You can then displaythe images corresponding to several or all of the bands inthe cube side by side.

The Thumbnail viewer is available from the Maps treeand the Files tree. When you open the Thumbnail viewerfrom the Files tree, thumbnails of the full extents of theimage are created for each channel. When you open theThumbnail viewer from the Maps tree, thumbnails of asection of the image are created for each channel. Thesection used for the thumbnail is a 256-by-256 pixel area

centered on the cursor in the image.

In Black and White mode, you can click on an individualimage from the tiled image array. Your image is thenhighlighted in white and displayed, full size, in the viewpane as a black-and-white image.

You can also work in RGB mode to select three imagesfrom the tiled image array, which are then outlined in red,green, or blue respectively. The corresponding compositeRGB image is displayed, full size, in the Focus window.You then have the option of clamping and stretching thetiled image, or each of the RBG images individually toproduce an optimal RGB image.

With the Reload button you can limit the contents of theThumbnails viewer to only the thumbnails that interestyou. You can create thumbnails of a feature bymagnifying the feature in the Focus view pane and thenclick Reload. Focus will recreate the thumbnails using theextents visible in the Focus view pane. You can set theoptions in the Thumbnails viewer and then click Reload.Focus will load the thumbnails according to the optionthat you set. For example, you can enter specificchannels in the Display ranges box and when you clickReload only thumbnails of those channels will appear inthe Thumbnails viewer.

1. Open a file that contains raster channels.2. Click the layer in the Maps tree or in the Files tree.3. From the View menu, click Thumbnails.

About the Thumbnails viewer

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The following is a list of the controls in the Thumbnailsviewer:

Display Range:

Allows you to specify the channels to be viewed. Thedefault is all channels. You can either specify the channelnumber or the wavelength. The wavelength is availableonly if the metadata contains band centers.

Channel:

Allows you to control the entries in the panel. If this isselected, then all of the entered values (display range,color components) correspond to channel numbers in thefile.

Wavelength:

Allows you to control the entries in the panel. Whenselected, all of the entered values (display range, colorcomponents) correspond to wavelengths stored in themetadata segment in the file. When selected, the channelnumber has to be passed in order for the images to bedisplayed properly.

Intensity Normalization:

When selected, the LUT applied to each thumbnail iscalculated using the histogram for that thumbnail (forexample, the first thumbnail is channel 1 and the LUTapplied to it will use the minimum and maximum from thatchannel. The second thumbnail is channel 2 and the LUTapplied will use the minimum and maximum from channel

2, and so on). If the option is disabled, the minimum andmaximum of the entire range of spectral bands in the fileare used to apply the LUT.

Grayscale:

Allows you to display a single thumbnail. This thumbnailis highlighted by a white box. Only one thumbnail in theviewer can be highlighted at a time. The channel numberof the selected thumbnail displays in the box next to theGrayscale option. When the option is enabled, the Red,Green, and Blue buttons are unavailable.

RGB:

Allows you to select three thumbnails to display in anRGB format. This works in the same manner as the AddLayer Wizard. If you enable the RGB option, the Red boxis active and the first thumbnail selected is assigned tothe red color component and is highlighted with a redbox. The number of the channel is displayed in the boxnext to the Red button. The second thumbnail selected isassigned to the green color component and is highlightedwith a green box. The third thumbnail selected isassigned to the blue color component and is highlightedwith a blue box. If you want to change a thumbnail in oneof the color components, you must click the colorcomponent and select a new thumbnail.

OK:

Adds the selected thumbnails to the Maps tree. If no Mapor Area is present, the thumbnails are added to the Maptree list. If you have only selected one thumbnail, it is

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displayed as a black-and-white layer. If you haveselected three thumbnails, the layer displays as an RGBimage layer.

View:

Allows you to view the selected thumbnails as full imagesin the view pane without closing the Thumbnails viewer.For each new selection, a new layer is added to the Mapstree. If no Map or Area is present, the thumbnails areadded to the Map tree list. If you have selected onethumbnail, it is displayed as a black-and-white layer. Ifyou have selected three thumbnails, the layer displays asan RGB image layer.

Cancel:

Closes the panel without saving.

Help:

Opens the Help for the panel.

The Thumbnails tool bar has the following commandbuttons

Zoom to Overview:

allows you to zoom to the overview of the entire tiledimage (all thumbnails).

Zoom Interactive:

lets you zoom into the tiled image.

Zoom In and Zoom Out

zooms in to and out of the tiled image.

Thumbnail Overview:

allows you to zoom to the overview of an individual tilewithin the tiled image.

Pan:

pans the tiled image.

Select Channel:

Selects a thumbnail for display. It is automatically activewhen you choose either the Grayscale or RGB option.

1. In the Thumbnails viewer, click Pick BW.2. Click a thumbnail.3. Click OK.

Layer Selection

When you have several layers in a file, you can quicklypick a single layer for input, output, or display with theLayer Selection tool.

Using the Thumbnails viewer

1. In the Thumbnails viewer, type in the Displayranges box the band or channel numbers that youwant to view to view.

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2. Click Channel if the values in the Display rangesbox represent channel numbers or clickWavelength if the values represent wavelengthsstored in the metadata segment in the file.

3. Enable the Intensity Normalization check box touse the minimum and maximum values in the imageto calculate a histogram and apply it to thethumbnail. When the Intensity Normalizationcheck box is disabled, the histogram includes theentire range of values from all the channels.

4. Click Grayscale if you want to view the image as agrayscale layer and click the thumbnail that youwant to view.

5. Click RGB if you want to view the image as an RGBlayer. Click in order the thumbnails that you want touse for the red, green, and blue channels.

The thumbnail is highlighted in the color of thecorresponding channel and the channel number isdisplayed in the corresponding box.

6. Click View.

Selecting grayscale and RGB layers

To change the displayed raster layer in a map:

1. In the Thumbnail viewer, right-click a layer in thered, green, blue, or grayscale color component.

2. Click More.3. In the Layer Selection dialog box, select a new

layer and click OK.

To select input or output layers:

1. Select More from the Input list box.2. In the Layer Selection dialog box, type a layer

number in the Layer number box.3. Click Enter.4. Click OK.

You can also select output layers by following thisprocedure with the Output list box. The Layer Listdisplays all of the channels in the file. When youclick a layer, the layer is highlighted and the numberof the layer is identified in the Layer Number box.The OK button accepts the layer as the new input.

Visualizing data with the 3-D datacube

The 3-D Data Cube is an independent graphical tool thatdisplays a three-dimensional data model. You can workin the view pane while the 3-D display is active. You canwork with any multi-layer data, including hyperspectraldata.

The 3-D Data Cube helps you to get a sense for thestructure of the data you are working with by allowing youto assess the number and nature of spectra endmemberspresent in a scene. Hyperspectral data often achievesvery large file sizes. You can see the spectral bandswhere there is high atmospheric absorption and thus verylittle signal reaching the sensor - black layers. In largefiles, to facilitate faster rendering, rotation, andexcavation of the data cube, you must create a subset if

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the data is not v-cube compressed data.

You can use all data bit depths, but the 3-D Data Cube isoptomized for 16-bit data. The 3-D Data Cube acceptscompressed, decompressed, and raw hyperspectral files.Files must contain wavelength information. You can usethe cube even if only one image channel has wavelengthinformation.

The 3-D Data Cube can display, rotate, and excavatethree-dimensional data. The tool displays the cube in anarbitrary orientation, with a rectangular cutout, usingparallel projection.

1. Select an image file in the Maps tree.

You can use B&W, multispectral, and hyperspectraldata.

2. From the View menu, click 3-D Data Cube.

By default, enhancements applied to data layers inthe view pane are applied the top layer in the 3-DData Cube.

About the 3-D data cube controls

The 3-D Data Cube viewer has a menu bar and toolbarthat are independent of the view pane. The viewer alsoincludes controls that let you zoom, rotate, and excavatethe cube image.

3-D Cube Menu Bar

The 3-D Cube menu bar lets you control several aspectsof the 3-D viewer and the data you are viewing.

File:

The File menu lets you import image files, load PCTlayers, and exit the 3-D Data Cube.

Import Image:

Opens the Import Image dialog box.

Load PCT:

Opens the Select PCT Layer dialog box. (See About theSelect PCT Layer dialog box on page 98 )

Exit:

Closes the 3-D Data Cube.

Edit:

Lets you edit a PCT and change the background color ofthe 3-D viewer.

Edit PCT:

Opens the PCT Editing dialog box. (See Adjusting thepseudo-color for single values on page 241 )

Background Color:

Opens the Change Color dialog box.

View:

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Lets you show or hide the image layer and the cubesides, and allows you to zoom the image in the viewer.

Image Layer:

Shows or hides the image portion of the data cube.

Cube Sides:

Shows or hides the cube sides portion of the data cubeexcavation.

Zoom To:

Opens the Zoom sub-menu.

3-D Data Cube Toolbar

The 3-D Data Cube toolbar lets you save files, editpseudo-color tables, zoom and pan your image, andenable the cube rotation.

Save:

Opens the Export Image dialog box, which lets you savethe file you are viewing to a new location.

Pseudo-color Table:

Opens the PCT Editing dialog box. (See Adjusting thepseudo-color for single values on page 241 )

Overview:

Displays an overview of the 3-D image.

Zoom Window:

Lets you zoom the image by clicking in the 3-D image inthe 3-D window.

Zoom In:

Makes the 3-D image larger.

Zoom Out:

Makes the 3-D image smaller.

Zoom 1:1:

Shows the 3-D image at 1:1 scale ratio.

Pan:

Lets you pan the 3-D image within the 3-D window.

Rotate:

Lets you rotate the 3-D image along the X, Y, and Z axis.

Cube Excavation

The Cube Excavation Area has text and slide controlsthat let you view a rectangular section of the layers in thecube. You can change the shape and the depth of theexcavation using the slide controls. When you use a

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wheel mouse, you can lock the excavation of the X, Y, orZ plains of the cube. You can also lock all three at onceand change the view of the excavation with your wheelmouse.

X:

Changes the horizontal axis of the cube excavation. TheX option box lets you lock the horizontal axis excavationwhen you use a wheel mouse.

Y:

Changes the vertical axis of the cube excavation. The Yoption box lets you lock the vertical axis excavation whenyou use a wheel mouse.

Z:

Changes the depth of the cube excavation. The Z optionbox lets you lock the depth excavation when you use awheel mouse.

Flip Controls

The Flip controls change the orientation of theexcavation.

Flip X:

Flips the X axis from right to left.

Flip Y:

Flips the Y axis from right to left.

Flip Z:

Flips the Z axis from top to bottom.

Using the Excavation Controls:

You can control height, width, and depth of the excavatedportion of the cube. When you use the slide control, theimage and the number above the slide control areautomatically updated. The minimum for each box is 1;the maximum number is the number of layers in the dataset. The maximum for the X axis is the maximum numberof pixels displayed in the Focus view pane. Themaximum for Y is the maximum number of linesdisplayed in the Focus view pane, and the maximum forZ corresponds to the number of image channels in thefile. If the image is at Zoom to Overview, the maximum Xand Y are the extents of the image. Each single-digitincrement removes one pixel, line, or channel from thedisplay.

The excavation is determined and applied by defaultwhen the cube is opened. The starting point of theexcavation is the lower-right corner, X max and Y max,and the top most image layer Z min. You can flip theexcavated area a full 180-degrees in the X, Y, or Zdimensions using the Flip buttons.

About the Select PCT Layer dialog box

The Select PCT Layer dialog box lets you choose analternative pseudo-color table (PCT) for the data

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displayed in the 3-D Data Cube viewer.

Input:

Provides a way to locate and apply a different PCT layer.

File:

Lets you choose a file where the PCT layer is located.

Browse:

Opens a File Selector dialog box to locate files not listedin the file box.

Layer:

Lets you choose a PCT layer from the file selected in theFile box.

Selecting colorsThere are several cases where you need to createcustom colors. For example, you can choose customcolors for vectors, points, polygon fills, training areas, andmore. In each case a color selection panel is available forcreating custom color. The color panel may differ,depending on the task you are performing. Custom colorsare created using a combination of three basic colorpalettes.

Color palettes

Basic Colors:

This is a palette of 49 basic colors that are preset andcannot be modified.

Color Continuum:

This is the palette of infinite colors in the middle of thedialog box. This palette is made up of all the possiblehue/saturation combination of values.

Lightness/Intensity Scale:

This palette controls the brightness of the color youcreate. When you choose the Gray color model, theLightness/Intensity Scale is the only available palette.

The color you create using the palettes is displayedalongside the color that is being replaced. The numericrepresentation of the new color appears in a series ofdata entry fields. You can edit the entries in these fieldsand the new color changes accordingly. The number offields present corresponds to the chosen color model.

Color models

RGB:

This is one of the Additive Color models and is based onlight emitted from a source, such as a computer monitor.It has three primary colors: red, green, and blue. All thecolors on a screen are produced by combining thesethree colors in various proportions.

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CMYK:

This is one of the Subtractive Color models and is basedon light being absorbed and reflected by paint and ink.This model is often used when printing. The primarycolors are cyan, magenta, yellow, and key (black).

HLS/IHS:

This is a more intuitive model based on the way weperceive color. The primary components are hue,lightness or intensity, and saturation.

Gray:

This is a continuum of gray values. The gray scaleranges from pure black to pure white.

To select a basic color value

1. In the Basic Colors palette, click a tile.

The Red, Green, and Blue values change to matchthe selected color. In addition, the color appears inthe New box and the slider control changes positionto show the value for the lightness and intensity ofthe new color.

To obtain a more precise color in terms of shadeand strength

1. In the Color Continuum, click a value.

To control the brightness of the color

1. Click the slide control and move the arrow up ordown to increase or decrease the lightness andintensity of the color.

To control color values at the pixel level in theRGB model

1. Click the arrows for the Red component.

This increases or decreases the numeric value ofthe red pixels.

2. Click the arrows for the Green component.

This increases or decreases the numeric value ofthe green pixels.

3. Click the arrows for the Blue component.

This increases or decreases the numeric value ofthe blue pixels.

To change the color model

1. Click the Model arrow and choose one of thefollowing:

• RGB: changes to a red, green, and blue colormodel

• CMYK: changes to a cyan, magenta, yellow,and black color model

• HLS/IHS: changes to a 3-D color model• Gray: changes to a grayscale model

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2. Click OK.

Setting options and preferencesYou can customize how Focus handles certain featuresand how it uses your system resources with the Optionsdialog box opened from the Tools menu. The Optionsdialog box is divided into two parts. On the left is a list ofoptions. When you select an option, the right side of thedialog box changes to give you access to the preferencesfor that option. The Options dialog box lets you customizethe following features:

Table 6.

Option Controls

General interface Cursor and menupreferences

Warnings Interface warningpreferences

Layers Zoom and rasterpreferences

Default representation Default data-typerepresentations

Vector editing Vector editing tolerances

Memory cache Undo, tiling, total, andvector caching

Overview window Rasters, vectors, andcolors

Zoom window X and Y sizes, tools, andstatus bars

Option Controls

Layer Manager Visible column options

OpenGL settings 3-D Data Cubepreferences

Setting shape and colorpreferences

View pane selectionpreferences

Setting up a digitizingtablet using Wintab Tablet setup

Setting up a GPS receiver Receiver setup

Measurement tools Units and reportpreferences

General interface

The General interface option includes a Warningspreferences sub-category. General interface optionsinclude:

Render white tiles

Delays the rendering of the image when you pan until yourelease the pointer. When Render white tiles is enabled,previously unviewed sections of the image appear whiteas you pan until you release the mouse button. WhenRender white tiles is disabled, you can pan withcontinuous rendering of the image, which can result indecrease in performance depending on the size of theimage.

Reload previous project on startup

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Reloads the previous project on start-up.

Show

Shows and hides tabs, message bars, the overviewwindow, the legend in the Maps tab, and ToolTips.

Cursor

Customizes the shape, size, and color of the cursor. Youcan choose from none, cross, empty cross, target,bracket target, and dot cursors.

Warnings

The Warnings option allows you to disable commonwarning messages. By default, all warning messages areenabled. To deactivate a particular warning message,disable the check box next to it.

You can choose from the following Warningmessages:

Attempting to view data with METER projection:

This message appears each time you open a layer ifFocus which has METER projection assigned. Some fileformats do not save projection information but do havebounding coordinates. Such layers are assigned aMETER projection by default. This warning message canbe useful for remembering to assign the appropriateprojection to the data.

Attempting to view data that has to be reprojected:

This message appears when you try to add data to aproject that is not the same projection as the active map.When you do this the new data is reprojected to theactive Map projection. This warning message can remindyou that the project has not been saved in the sameprojection.

Creating a new area in order to view data that can#tbe reprojected:

This warning message appears when data that cannot bereprojected is added to an active Map that already has anassigned projection. Data that cannot be reprojectedincludes layers or files that have METER or PIXELgeoreferencing assigned to them. In this case, a NewArea is created for the layer.

Modifying a layer's representation if it may affectother layers:

This warning message appears when a representationthat is linked to more than one layer is edited. By editingthe representation style of one layer that is linked to anRST, the representation style of another layer that is alsolinked to the same RST may be changed if the sameREPCODE is used by both layers. This warning messagecan let you know that the representation changes beingmade to one layer may also affect another layer.

Required input is missing in the Layer Manager:

This warning message appears when information for a

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particular Layer Manager operation is missing and thesystem cannot carry out the operation you haverequested.

Fully within spatial operator not available forthematic rasters:

This warning message appears as a reminder that youare attempting to use the Fully Within tool on a thematicraster.

Layers

The Layers option allows you to specify variouspreferences for opening and displaying layers in Focus.For example, you can change the zoom level whenadding a new layer to a project. This is controlled by theWhen Loading menu. The following zoom levels areavailable:

Zoom to Overview

Displays an overview of the map each time a new layer isopened.

Zoom to Full Extents of Layer

Displays the full extents of the newly opened layer.

Don't Change the Zoom

The current zoom level is maintained when a new layer isopened.

When a new raster layer is opened, you can have a 1:1zoom level applied by default. This is specified byenabling the Load Rasters at 1:1 resolution check box. Ifyou open several rasters at the same time, the defaultenhancement may be unsatisfactory for all rasters. If youintend to regularly open several rasters at the same time,it may be advisable to clear the Load Rasters at 1:1resolution check box.

There are two menus in the Rasters area that specify thedisplay properties of rasters when they are opened intoFocus: the Default resampling method and Default visualenhancement.

The Default resampling method specifies how the rasterwill be resampled for viewing when at greater than 1:1resolution. The resampling options are Nearestneighbour, Bilinear interpolation, and Cubic convolution.

The Default visual enhancement menu specifies thedefault visual enhancement that will be applied to a newlyopened raster. The default visual enhancements offeredare None, Linear, Root, Adaptive, Equalization, andInfrequency.

The Default overview area contains a menu that allowsyou to specify the preferred overview generation method.The overview generation methods offered are Nearestneighbour, Block average and Block mode.

Default representation

The Default representation option consists of a DataType area and a Preview pane. You can change the

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default point, line, and polygon representations for vectorlayers.

When you open a vector layer, the default representationset in the Options dialog box is applied to the layer. Thisdefault remains a property of the layer while the layer isopen.

Changing the default representation in the Options dialogbox does not affect the vector layers that are currentlyopened in the viewer. Changes to the settings in theOptions dialog box affect only those layers that aresubsequently opened.

Changes to the default representation for vector layerscurrently open in the viewer are made in the Defaultrepresentation area of the Vector Layer Properties dialogbox. You can also change the default point, line, andpolygon representations for your vector layers, just likethe Data Type area. The changes are applicable to thecurrent session only. When you open the layers in a newsession, the default representation set up in the VectorLayer Properties dialog box is lost and replaced with thesettings in the Options dialog box.

To make your settings permanent, set the defaultrepresentation in the Options dialog box; also, set up thedefault representation before you open any vector layers.

Vector editing

The controls in this option are used for creating andediting vectors. The Vector editing option sets the units

and tolerances for Search, Snap, and Weed verticestolerances in either pixels, meters, or feet. By default, thetolerances are measured in pixels. This option also setsthe snap feature for digitizing operations.

Snap Tolerance:

The snap operation is only used on a line or at the start ofan area edit function. When the choice is to snap a line orarea start to a vertex or a line, the snap tolerance is usedto limit the lines or vertices that are available to snap to,given the cursor's current position.

Snap Automatically:

Is only used in a line or at the start of an area editfunction. The snap default dictates whether a line or anarea is started or ended with a snap when you want tostart or end the line, or begin the area while still within thedistance specified by the Snap Tolerance.

Search Tolerance:

Limits the cursor search for a vector feature to select.

Weed Vertices Tolerance:

Is used when digitizing line and area data. The value ofthe weed vertices tolerance specifies the minimumdistance between the last vertex digitized and the currentpointer position within which another vertex can bedigitized.

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To set the snap tolerance

1. Type a value in the Snap tolerance box.2. Choose a measurement unit from the Snap

tolerance list box.

The default unit is pixels.

To activate the snap operation

1. Enable the Snap check box.

When digitizing, you can still activate or deactivatethe snap operation by holding the Alt key whilestarting or ending a line or starting an area.

To set the tolerance for a vector search

1. Type a value in the Search tolerance box.2. Choose a measurement unit from the Search

tolerance list box.

The the default unit is pixels. Clicking the cursorwithin this tolerance of a feature selects it. Clickingwithin this tolerance of a vertex or node that is on apreviously selected line highlights the vertex ornode.

To set the tolerance for weed vertices

1. Type a value in the Weed vertices tolerance box.2. Choose a measurement unit from the Weed

vertices tolerance list box.

The default unit is pixels.

Memory cacheThe Memory cache preferences let you configure systemmemory for various memory cache options. You canadjust for Undo/Redo, Tiling, Total limit, and Vector readcache.

The memory cache panel provides a way to limit systemmemory usage for the current application. The total limitis the maximum amount of memory caching available onyour system.

Undo/Redo:

The Undo/Redo box lets you specify, in kilobytes (1024KB = 1 MB), the amount of memory up to 25 MBsavailable for undo and redo steps. (See Optimizing theUndo/Redo options on page 106 )

Clear Undo/Redo cache:

Clears all cached undo and redo operations from yoursystem.

Tiling:

Lets you specify, in kilobytes, the amount of memoryavailable for raw image inputs and display cachingoutput. (See Optimizing the tiling cache on page 106 )

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Clear tiling cache:

Clears all cached tiling operations from your systemcache.

Total limit:

Lets you specify, in kilobytes, the limit of memoryallocation. When zero is entered, the system uses all ofthe available system memory as the memory cache limit.(See Setting the total cache limit on page 107 )

Default memory usage:

Re-sets the total limit of cache to the default level. Thedefault memory usage is one-half of the system memory.For example, if a system has total memory of 500 MB,the default memory usage command sets the cache to250 MB.

Vector read cache:

Lets you enter a value for the number of lines, polygons,and points that can be cached by the system. The vectorread cache is independent of values set in the Total limitbox. (See Setting the vector read cache on page 107 )

Default read cache:

Re-sets the default number to 4,000 cached shapes.

Optimizing the Undo/Redo options

You can control how much memory Focus allocates toundo and redo operations. For example, when you areburning a shape within a raster image, the old state of theapplication is kept in memory. The size of the boundingbox of the new shape, in pixels and lines for raster datatypes, and the number of input channels are all storedtemporarily as an undo/redo step. This can use a lot ofsystem memory. The number of undo steps cannot becomputed based on the size of the undo/redo cache.Each undo step requires varying amounts of memory.

The Undo/Redo box lets you enter a value in kilobytes.This setting is affected by the total limit setting which iscomposed of both undo/redo and tiling settings. Adjustingthe undo/redo setting lets you make sure that the totallimit is divided, based on the way you work, betweenundo/redo and tiling.

Optimizing the tiling cache

The larger the data set, the more memory a systemneeds to function effectively. For example, an 8-bit imagemeasuring 512 pixels x 512 lines requires 1 byte for eachpixel, or 1 MB of information for each 8-bit raster layer.With very large files, you can experience memory deficitsrequiring more memory to display requested data. If thetiling cache is set too low, a system will swap databecause it is designed to de-allocate and then re-allocatememory to stay within the limits of your data.

The tiling cache changes the way you can render animage in the view pane. When you work with very largeimages, you can increase the memory allocated to tiling,which has a direct impact on rendering. By increasing the

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size of the tiling cache, you increase the speed of imagerendering.

Setting the total cache limit

The total cache limit is the sum of the undo/redo and thetiling cache. If both are set to zero, the limit becomes thetotal limit for the sum of the two. You can specify, inkilobytes (1024 KB = 1 MB), the limit of memoryallocation. When zero is entered, the system allocates1/3 of the RAM installed on the system as the total limit ofmemory cache.

Setting the vector read cache

The vector read cache increases performance with verylarge data sets. This is a GDB vector cache and isindependent of the value set in the Total limit box. Whenyou increase the vector-read cache value, the systemdoes not need to access the data from the shapes savedin the data files on your hard disk. The result is animprovement in overall system performance.

Overview windowThe Overview window option allows you to set the displayproperties of the overview window. For more informationon the overview window, see Zooming using theOverview window on page 79 .

In the Show area there are check boxes for both Rasterand Vector. These control which type of data will bedisplayed in the overview window. A check mark

indicates that the data type will be shown in the overviewwindow.

The View box color list box controls the color of the viewbox in the overview window. The View box color list boxcontains a color palette with 49 available colors.Additional colors are available by clicking More.

Zoom windowThe Zoom Window option allows you to set the displayproperties of the zoom window.

The default size of the zoom window that is launched iscontrolled by the Default X-size and Default Y-size spinboxes. These sizes can be adjusted by using the arrowkeys in the Default X-size and Default Y-size spin boxes.Alternatively, you can type a desired default size directlyinto the boxes.

If the Keep equal check box is enabled, the value of theX-size and Y-size of the zoom window will be the same.

The Icon toolbar check box controls the Icon toolbar inthe zoom window. If enabled, the Icon toolbar displays atthe top of the zoom window.

The Show status bar check box controls the status bar inthe zoom window. If enabled, the status bar displays atthe bottom of the zoom window.

Layer Manager

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The Layer Manager option allows you to specify the fieldsappearing in the Layer Manager. By default, all of thecolumns in the Layer Manager display. You can removefields in the Layer Manager display by disabling theappropriate check box. (See Using the Layer Manager onpage 31 )

Open GL settingsThe Open GL settings has preferences for setting themaximum texture size of the 3-D Data Cube. The systemcan determine the maximum texture size or you can setthe maximum texture size manually.

Setting shape and color preferences

The selection preference option lets you change thedefault condition of selected points, lines, polygons, text,and rasters. To set selection options, click the + next tothe Selection option. When you choose Selection in theoption list, there are two initial options.

Consider interior of polygon:

Lets you select a polygon by clicking inside the polygonboundaries, even if it is not a closed figure.

Select only if fully contained:

Lets you select a polygon by clicking inside the polygonboundaries only if the polygon is a closed figure.

Points:

Allows you to change how selected points associatedwith a layer appear. The color option allows you tochange the highlight color of selected points. The Widthoption is used to specify the width of the outline thatappears around the points. The default value is 1.

1. With several points selected, choose a color fromthe Color palette.

2. Enter a value that represents the width of the outlinethat appears around the points from the Width spinbox.

3. Click Apply.

Lines:

Allows you to change the color and width of a selectedline associated with a layer.

The Width option is used to specify the width of the lineused to highlight one or more selected lines. The defaultvalue of the highlight width is 1.

Modifying a selected line

1. Choose a color from the Color palette.

To select a color other than those displayed in thecolor blocks, click More and create a new color.

2. Enter a value that represents the width of a line inthe Width spin box.

3. Click Apply.

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Polygons:

Allows you to change the outline and fill of a selectedpolygon.

Opacity refers to the degree of opaqueness. A value of100%, means that you cannot see another object throughthe fill color. An opacity value of 0% means you can seethrough the fill color completely.

Modifying a selected polygon

1. In the Outline area, choose a color from the Colorpalette.

To select a color other than those displayed in thecolor blocks, click More and create a new color.

2. Enter a value that represents the width of thepolygon outline in the Width spin box.

3. In the Fill area, choose a color from the Colorpalette.

To select a color other than those displayed in thecolor blocks, click More and create a new color.

4. Enter a value that represents the percentage of thefill opacity in the Opacity spin box.

5. Click Apply.

Texts:

There are three Texts preference options.

The Color option allows you to the change the insertionpoint and highlighted text color.

The Highlight insertion point option allows you to seewhere text associated with a layer is inserted.

The Highlight text option allows you to highlight theselected text.

Applying preferences to selected text

1. Choose a color from the Color palette.

To select a color other than those displayed in thecolor blocks, click More and create a new color.

If you want to highlight the text insertion point,enable the Highlight insertion point check box.

If you want to highlight the selected text, enable theHighlight text check box.

2. Click Apply.

Changing the style for hatches

You can change the style, color, and size of rasterhatches.

• Choose a hatches style from the Hatches palette.

To select a style other than those displayed in thehatches blocks, click More and choose a newsymbol.

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Changing the raster color

• Choose a color from the Color palette.

To select a color other than those displayed in thecolor blocks, click More and create a new color.

Changing the raster size

• Enter a value that represents the raster size in theSize spin box.

Setting up a digitizing tablet usingWintab

You can connect a digitizing tablet to your system anduse it with Focus. The Digitizing Tablet option lets you setup a digitizing tablet.

Before using a digitizing tablet, you must connect it to thecomputer and set up the software to communicate withthe tablet. Focus supports Wintab and provides severalother tablet drivers.

1. Ensure the digitizing tablet is connected accordingto the manufacturer instructions.

2. From the Tools menu, click Options.

3. Select Digitizing Tablet.4. Enable the Wintab device option.

If your device is Wintab enabled, The Wintabdevice option is enabled by default, and the Devicesetup area is populated with the Wintab settings.

5. Enter the values of components by reading themfrom Wintab.

6. Click Test Connection.

The Digitizing Tablet Connection Testing dialogbox opens. See Testing the digitizing tabletconnection on page 111

Setting up a digitizing tablet using a driver

1. Ensure the digitizing tablet hardware is connectedaccording to the manufacturer instructions.

2. From the Tools menu, click Options.3. Select Digitizing Tablet.

By default, the Generic device option is selected,and the Wintab device option is unavailable. TheDevice setup area is populated with defaultsettings.

4. Choose a hardware communication port from theDevice list box.

5. Choose a driver that matches your device from theTablet list box. Note that the SummaSketch IIIdigitizer is no longer supported, however, the ASCIIBCD report format is supported.

6. In the Communication settings area, choose abaud-rate, data-bit, parity, and stop-bit value fromthe appropriate list boxes, according to the digitizing

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tablet manufacturer specifications.7. Click Test Connection. See Testing the digitizing

tablet connection on page 111

The setup is successful if a device string appears inthe Device String box in the Digitizing TabletConnection Testing dialog box. If no device stringdisplays, click OK to reset the device setup andcommunication settings.

Testing the digitizing tablet connection

The Digitizing Tablet Connection Testing dialog boxshows information to help you determine if the computeris properly communicating with the tablet and to help PCISupport diagnose digitizer problems.

When the dialog box is opened, all of the boxes areblank. When you click the digitizer puck, these boxes arepopulated with device string information. The devicestring is not visible when using Wintab.

Assigning text actions and modifiers

When you have successfully connected the digitizingtablet, you can assign actions to the puck buttons on yourdigitizer. In the Puck button assignment area, the firstfour buttons have the following default assignments:

Table 7.

Button Action Modifier

1 Mouse Click None

2 Enter None

3 Escape None

4 Delete None

1. Enter a puck button number in the Button spin box.

If an action is already associated with this button,you can update both the Action and the Modifierlist boxes. The Action and Modifier list boxes areset to None when neither an action nor a modifierare associated with a button number.

2. Choose an action from the Action list box.3. Choose a modifier from the Modifier list box.4. Click Apply.

Setting up a GPS receiver

The GPS receiver option lets you set up a GPS receiverto use with Focus. You can set up the serial portconnections and parameters to connect a compatibleGPS receiver. Only GPS receivers that support theNMEA protocol are supported. Most GPS receiverssupport this protocol, which allows devices from differentvendors to communicate over a serial connection in amarine setting. NMEA is used across the GPS industry.The supported formats in the setup panel are based oncommon data output formats. For example, theNMEA-0183 (ASCII) format. Focus reads only the X, Y,and Z coordinates from the NMEA format. Coordinatessupplied by the NMEA format are latitude and longitude,using a WGS84 ellipse.

Before setting up a GPS receiver, make sure a GPS

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device is connected to a serial port on your computer.

Device settings:

The GPS receiver options are specifically related tosetting up the GPS that you are using. The Device boxspecifies the port where you have attached your GPS. Bydefault, this option is set to COM1. See the informationprovided with your GPS unit about which port to use.

1. Enter the connection port that will be used in theDevice box.

2. Choose a baud rate, data bit, parity, and stop bitfrom the appropriate list boxes in theCommunication settings area.

You can change values back to the default valuesby clicking Restore defaults.

3. Enter a value that represents how frequently thepoints should be captured from the GPS, from fourto 300 seconds, in the Capture every spin box.

4. Click Test connection.

The GPS connection is automatically tested in theGPS Connection Testing dialog box.

Testing the GPS connection

The GPS Connection Testing dialog box opens when youclick Test connection. You can determine if theconnection to your GPS has been made correctly. Theconnection is tested automatically each time you click theTest Connection command button in the GPS receiverpane. You can also manually test the connection byclicking the Try Again button at the bottom of the GPS

Connection Testing pane.

If the GPS connection is successful, the Device Stringbox displays the current geographic coordinates from thereceiver. The Location area shows the elevation as longas the GPS can display elevation.

If the GPS connection is unsuccessful, an error messageis generated. If an incorrect device (for example, adigitizing table) has been connected, the panel will showa device string. The location information will not bedisplayed.

If you want to manually re-test the connection, click TryAgain.

Measurement toolsYou can set the behaviour of the Measurement tools inthe view pane. Linear, Area, and Angle options areavailable. To read the measurements from the view pane,enable the Generate Report to Window check box. SeeReading the Measure tool report on page 208

Changing display optionsWhen you print a map, it is identical to the map on yourcomputer screen by default. There may be times whenyou do not want your printed work to look exactly likeyour screen. The display Options panel lets you turn offthe default WYSIWYG feature. There are several reasonsfor disabling the WYSIWYG feature. For example, yoursoftware performance may improve when WYSYWYG is

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turned off and the view pane appears less cluttered. (SeeAbout the Display Options dialog box on page 113 )

About the Display Options dialog box

The Display Options dialog box lets you turn off thedefault WYSIWYG feature. It also provides WYSIWYGoptions for width/fill, pattern, text, and zoom scaling.

WYSYWYG Options:

Allows you to switch the WYSYWYG feature on or off, orto choose from a set of custom WYSYWYG options.

On:

Enables WYSYWYG for map publishing.

Off:

Disables WYSYWYG for map publishing.

Custom:

Enables the width/fill, pattern, and text options.

Width Fill:

Displays the map with WYSIWYG line weights andpolygons filled.

Pattern:

Displays the map with all the patterns visible. Forexample, a pattern can be a broken line or other symbol,such as sand, transmission lines, or forest.

Text:

Displays the map with its text attributes applied (forexample, font, height, and so on).

Scale representation when zooming:

Changes the vector display size relative to the zoomlevel. When you zoom in, symbols get bigger and linesget wider.

Customizing the Focus toolbars

You can customize the Focus toolbars to show or hidespecific tool groups from the Toolbar Configuration dialogbox.

1. From the View menu, click Toolbars and then clickCustomize.

2. Click in the Visible column next to a toolbar to showor hide it.

A check mark indicates that the toolbar is available.

3. Click OK.

About the Toolbar Configuration dialog box

The Toolbar Configuration dialog box contains a tablewith a list of toolbar options. You can select the toolgroups you want to see from the table.

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Toolbar:

Lists the available toolbars.

Visible:

Shows the option box for the toolbar listed in the Toolbarcolumn. A check mark indicates that the toolbar isavailable.

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Chapter 3Supported layer typesGeneric Database (GDB) technology is available inFocus. You can work with dozens of file formats andconvert them to PCIDSK. The following section outlinestechnical information for layers supported by GDB inFocus.

Focus and raster layersIn Focus, a GDB can have any number of raster imagelayers. Also referred to as channels or bands, a rasterlayer consists of a rectangular grid or array of pixels.Each pixel has associated digital numbers indicating itsdisplay brightness. Digital values can also representattributes other than radiometry.

A thematic raster layer can have a set of values,representing a crop type or a forest type, correspondingto the ground truth for a scene or image. Raster layerscan also contain values for continuous fields of datarelating to temperature, proximity to fire stations, orprobability of erosion. You can assign raster layer valuesmanually, automatically, or from the metadata associatedwith the raster layer.

In Focus, all raster layers have a data type and must

have the same width, measured in pixels, and height,measured in lines. Layers are presumed to correspond tothe same real-world region.

Focus supports four raster data types:

• 8-bit unsigned (8U): Each pixel is stored as onebyte of data, and can have an integer value from 0to 255.

• 16-bit signed (16S): Each pixel is stored in twobytes of data, and can have an integer value from-32768 to 32737.

• 16-bit unsigned (16U): Each pixel is stored as twobytes of data, and can have an integer value from 0to 65535.

• 32-bit real (32R): Each pixel is stored as four bytesof data, and can have an IEEE floating point valuebetween -1.2 x 1038 and 3.4 x 1038.

Focus can also use bitmaps as 1-bit raster layers. Whenbitmaps are used as graphic masks, they are stored asseparate layers.

File formats supported by GDB are mapped to one of thefour data types they most closely resemble. In somecases, mapping leads to loss of precision. For example, afile format that supports double precision (64-bit) floatingpoint values is mapped to 32R with a corresponding lossof precision. A data type with 4-bit integers in TIFF files,are mapped to 8-bit unsigned format with no loss ofprecision.

Raster layers are automatically numbered starting at 1. A24-bit TIFF file is represented as a three-channel rastercontaining the following assigned channels:

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• channel 1 - red• channel 2 - green• channel 3 - blue

Raster pixels are addressed as pixel and line locations inthe pixel array. The top-left corner is addressed (1,1) andappears at offset (0,0) from the origin. Pixel valuesincrease to the right, along the X axis, and line valuesincrease downwards along the Y axis.

Some calculations require operations at a finer level.Pixel values are divided to allow for more data. Forexample, the upper-left corner of the upper-left pixel is at0.0 and 0.0, and the lower-right corner of the upper-leftpixel is at 1.0 and 1.0. The centre of the upper-left pixel isat 0.5 and 0.5. The centre of the lower-right pixel of a1000 x 1000 image is at 999.5 and 999.5.

MetadataFocus uses the following metadata tags for raster layers:

• DEFAULT_PCT_REF - Reference to thepseudo-color table (PCT) segment for displaying animage in pseudo-color mode. This entry defaults theimage to pseudo-color display mode.

• DEFAULT_LUT_REF - Reference to a look-up table(LUT) segment for a default enhancement whendisplaying an image.

• SCALING_MIN - Default value to use as a minimumfor scaling an image channel to 8-bit for displaypurposes.

• SCALING_MAX - Default value for maximumscaling in an image channel to 8-bit for displaypurposes.

• NO_DATA_VALUE - Image value indicating no datais available.

• ELEVATION_UNITS - May be UNKNOWN (implicitdefault), FEET, or METRES. Primarily intended foruse with elevation channels and should beUNKNOWN for non-elevation data.

• Class_n_Name - Short name for a theme class in araster with #n# being the class number. Should beless than 9 characters.

• Class_n_Desc - Longer description for a class in araster.

• Class_n_Color - Color for displaying a particulartheme class. Value is the color encoding using theRGB (rrr ggg bbb) convention as seen in thePCLColor class.

• ACQUISITION_DATE - Date and time an imagewas acquired. The format of date is YYYY/MM/DDHH:MM:SS.

Segment organizationPCIDSK is a data structure for holding digital images andrelated data, such as LUTs, spectral signatures, groundcontrol points, and other data types. Each PCIDSKdatabase is a separately named disk file. You can haveany number of PCIDSK files, limited only by the diskcapacity of the computer. PCIDSK files can be sharedwith users on different computer platforms.

Segments are the parts of a PCIDSK database whichhold data related to the imagery in the database. Unlikeimage channels, disk space is not allocated for segmentsat the time the database is created; rather, disk space isdynamically allocated whenever a segment-generatingprogram is executed. A database can store up to 1024

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segments, provided you have enough disk space. Twelvekinds of information are stored as segments, namely:

Bitmaps [Type 101:BIT]

Bitmap segments are pseudo-images. They have thesame pixel and line dimensions as the image data on thePCIDSK file; however, each pixel of a bitmap is only 1-bitdeep. In other words, the gray value of a bitmap pixel canbe either zero (pixel not #on#) or 1 (pixel #on#). Forviewing purposes, bitmaps are opened to video in graphic(or bitmap) planes. Bitmap pixels with a value of 1 arevisible (they take on the color of the graphic plane).Bitmaps are used most commonly for delineating masksor training areas.

Vectors [Type 116:VEC]

Vector segments hold lists of (X,Y,Z) vertices, whichdefine point and line structures representing rivernetworks, political divisions, and so on. These segmentsalso contain attribute information in a number of differentformats and projection information.

Signatures [Type 121:SIG]

Signature segments hold statistical data that describe thespectral behaviour of a particular image feature (object).Signature segments are used as input during minimumdistance, parallelepiped, and maximum likelihoodclassification.

Text [Type 140:TEX]

Text segments hold attribute data (some quality, such asland use, or quantity, such as temperature) linked to thegray levels of a particular image channel or free-form text(legend information used during map generation orcommands to implement an analysis model). Otherspecifically formatted text segments include an AVHRRsegment containing calibration and orbital data, including:

• Satellite ID (name), orbit ID, year, day of year.• Spatial extent information.• A single GCP corresponding to the exact center of

the middle pixel from the first line of the outputimage.

• Orbital element/ephemeras data: epoch, inclination,right ascension, argument of perigee, eccentricity,mean motion, mean anomaly.

• Ascending/descending orbit flag.• Platinum resistance temperatures.• Internal target values for channels 3,4,5.• Gray level of space values for channels 3,4,5.• Up to 5 LUTs used to compress 10-bit data to 8-bit.

If a particular output channel is not 8-bit, no LUT forthat channel will be created. These LUTs are usedby the program named SST.

Georeferencing [Type 150:GEO]

Georeferencing segments hold mathematical transformsthat map all pixel locations in the database image to ageoreferenced coordinate system (such as UTM).

Orbit [Type 160:Orbit]

Orbit segments hold satellite ephemeras data, used inthe orthorectification process. This information is read

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from the original data source, or from a text file.

Look-up Table [Type 170:LUT]

LUT segments hold numerical tables that map imagegray levels to new gray levels.

Pseudo-Colour Table [Type 171:PCT]

Pseudo-colour segments hold numerical tables whichmap image DN values to a specific color. Colors aredefined by an intensity value (between 0 and 255) foreach of a red, green, and blue component.

Binary [Type 180:BIN]

Binary segments are created and used by PACEprograms. These contain internal-only information, suchas orthorectification models and neural networks.

Array [Type 181:ARR]

Array segments hold an array of numbers. They arecreated and used by PACE programs. They containinformation such as SAR-gain offsets and gain-scalingtables.

System [Type 182:SYS]

The system segment is used to hold binary informationthat you should not normally access directly. Systemsegments are not displayed by utility programs and areused to hold information such as metadata, overviews,and tiled-image data.

Ground Control Points [Type 214:GCP]

GCP segments hold pairs of (X,Y) coordinate positionsthat locate a point in an image and some other frame ofreference (either a vector segment, a map, anotherimage, or keyboard input of coordinates) for purposes ofimage correction, registration, and mosaicking.

Each segment has a numeric-type code. For example,GCP segments are type 214. This numeric code helpsyou locate a particular segment in a database. Whenlisting segments with the program ASL, you can create alisting by segment type. If you do not know the numericcode for a particular segment type, consult the list aboveor use:

AST

Database Segment Type Codes

Pseudo-color Tables

A PCT segment contains an array of 256 colors andassigns color values to 8-bit images. A PCT alwayscontains exactly 256 entries. File formats, such as TIFF,which may have color tables with less than 256 colors,assigns a value of zero to unused colors. There is nosupport for alpha channels in the table.

Look-up Tables

The LUT segment consists of 256 8-bit values, between 0and 255. It is used to apply enhancements to raster data.It can also be used to encode thematic class mapping.

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Ground Control Points

GCP segments contain up to 256 GCPs, which are usedto associate projection coordinates with locations on anuncorrected raw image.

GCPs can also be used to relate locations in any twogeoreferencing systems: in raw image coordinates and ina georeferencing projection system. The definitions of thegeoreferencing systems are kept as 16-character mapunit strings.

Projection parameters are not stored. Only projectionsthat are fully defined by the map unit string can be used;for example, UTM, Long/Lat, or METRE. Complexprojections, such as Transverse Mercator, cannot beused.

Each control point can have an elevation associated withthe location in an image. An elevation unit string is keptfor each system with values in meters or feet.

GCPs have the following associated values:

Id:

Unique numeric control point identifier.

System 1 X:

The X coordinate in the first georeferencing system andis a pixel located in the image.

System 1 Y:

The Y coordinate in the first georeferencing system andis a line location in the image.

System 1 Elevation:

The elevation of the location in the first georeferencingsystem. This has a zero value and is ignored byapplications.

System 2 X:

The X coordinate in the second georeferencing systemand is a location described in projection coordinates.

System 2 Y:

The Y coordinate in the second georeferencing systemand is a location described in projection coordinates.

System 2 Elevation:

The elevation in the second georeferencing system. Thishas a zero value when it is not used.

Bitmap (BIT):

A bitmap segment is a raster layer where pixels have avalue of 0 or 1. Bitmap segments are typically used tomask images when creating training areas inclassification.

Bitmaps are raster grids, similar to image layers, andmust have the same number of pixels and lines as otherraster layers in the database. The georeferencing

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associated with the raster layers is assumed to apply tobitmap layers.

Vector (VEC)

Vector layers or segments hold a set of related vectorsand can be points, polylines (arcs), whole polygons,topological polygons, or additional database records.

Vector objects in Focus are called shapes. A shape has aunique numeric identifier (ShapeId) greater than or equalto zero. A ShapeId is assigned chronologically beginningat zero.

Each shape has an associated record of attributes storedin the layer as part of the shape. Each shape has a list ofvertices recorded in double precision IEEE floating pointnumbers and has an X, Y, and Z value. Vertices arecoordinates in the vector georeferencing system.

Topological layersFocus lets you work with the layer attributes for severaltopological file formats. The following information showsthe required attributes for different formats:

Arc layers

Arc layers must contain the following attributes:

StartNodeId:

Contains the GDBShapeId of the starting node.

EndNodeId:

Contains the GDBShapeId of the ending node for thisarc.

LeftAreaId:

Contains the GDBShapeId of the left area polygon, orGDBNullShapeId if there is no area.

RightAreaId:

Contains the GDBShapeId of the right area polygon, orGDBNullShapeId if there isn#t such an area.

Node layers:

Node layers must contain the following attribute:

ArcIdList:

(GDBFieldTypeCountedInt) List of arc ShapeIds startingor ending at this node.

Each node should also have one vertex defining theposition of the node. A node layer must have ARC_REFand AREA_REF metadata pointing to the related arc andarea layers. It must also have a LAYER_TYPE ofTOPO_NODES indicator in metadata.

Area layers

Area layers must contain the following attribute:

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ArcIdList:

(GDBFieldTypeCountedInt) List of arc ShapeIds formingthe border of this area in clockwise order. Each ring isseparated by a GDBNullShapeId entry in the ArcIdList.

A topological area shape should have either zero or onevertex. If it has one, it will be presumed to be an internallabel point for the area. An area layer must haveNODE_REF and ARC_REF metadata pointing to therelated node and arc layers. It must also have aLAYER_TYPE of TOPO_AREAS indicator in metadata.

Representation Style Tables (RST)

The Representation Style Table (RST) is used todescribe and store the graphical attributes of a vectorlayer.

Each element is assigned an integer value called arepresentation code or RepCode. The representationconsists of a series of parts describing a drawing methodfor a shape.

Each part has the following information:

Priority:

Used to indicate how vector drawing components arelayered. Higher priority layers are drawn over lowerpriorities. This applies to different parts in arepresentation. It also applies to different shapes in alayer, and sometimes between vector layers in a view.

GeoGateway has the following drawing elements:

• Simple-line• Dash-line• Spaced-symbol• Simple-point• Point-symbol• Vector-text• Solid-polygon• Patterned-fill• Transparent-polygon

Parameters:

Each element has a set of parameters affecting thedisplay. For example, the parameters of the Simple-lineelement are width and color.

Importing, linking, and translatingdataAlthough GDB operates behind Focus, there are timeswhen you need to work with more than one file format.The import, link, and translate utilities expand your abilityto read, view, and process distribution formats, and read,edit, and write exchange formats. Use these utilities whenyou need to import different file formats to a PCIDSK file,link files, translate data across different formats, transferlayers, import ASCII files into your project, or export yourproject as an XML file.

With some geospatial file formats, the size andconfiguration of the data may cause slow-downs whenoperations and algorithms are applied to the data. Focus

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is optimized to use the PCIDSK format. Focus hasutilities to import, link, and translate file formats to let youget the most out of both PCIDSK- and GDB-supportedfile formats.

Importing files to the PCIDSK format

The import utility lets you work with any GDB-supportedformat in Focus by automatically converting it to aPCIDSK file. When the format is not supported by GDB,you must define the raw data with the Raw File Definitiontools. (See Using undefined image data on page 127 )

To import files into Focus using the Import File utility, youmust select a source and a destination file. The Importfile utility also has Interleaving and Overview options.

The Browse button opens the File Selector dialog box.Use this dialog box to select the file you want to importinto PCIDSK format.

Destination File:

Specifies the new PCIDSK version of the source file.Enter the file name and path directly in the DestinationFile box, or click Browse to launch the File Selectordialog box. The output file must not exist before importingthe file.

Format Options:

You can improve the performance of a file and save diskspace when you are using large files. There are several

interleaving and compression methods available forraster data.

Overview Options:

An overview is a reduced-resolution version of theimported image. Focus can open overviews faster thanfull resolution images and automatically creates a set ofoverviews for an imported image. Overviews canincrease the required disk space by as much as 15percent.

1. From the File menu, click Utility and then clickImport to PCIDSK.

2. From the PCIDSK Import dialog box, click Browsefor the source file.

3. In the File Selector dialog box, locate the file youwant to import and click Open.

4. From the PCIDSK Import dialog box, click Browsefor the destination file.

5. Choose a location for your destination file.

Note:You can also type the name of the file directlyin the Destination File box.

6. Type a name for your file in the File name box.7. Click Save.8. Select a format from the Format Options list box.9. Select a downsampling option from the Overview

Options list box.

If you want to disable the overview, select DisableOverview.

10. Click Import.

The file is not opened in the view pane. You must

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open the file separately.

Building raster overviews

The Build Raster Overviews dialog box lets you choosetarget files and layers, resample methods, and overviewlevels.

You can create overview levels in powers of 2, which letsyou obtain a minimum image size of 64 pixels in onedimension. Overviews can be created for file formats thatdo not natively support overviews. Overviews cannot becreated for a layer if one of its dimensions is less than 8kB.

1. In Focus, click the File tab if it is not alreadydisplayed.

2. Right-click a raster layer.3. From the menu, choose Overview Manager.

The Build Raster Overviews dialog box is displayed.

4. In the Build Raster Overviews dialog box, in theGeneral Information section, do one of thefollowing:

• click the File arrow and choose a file.• click Browse and choose a file.

5. Click the Layer arrow and choose a layer.

You can build an overview for all layers or for asingle layer, which lets you create differentoverviews for different layers.

The raster size and type are automatically displayedfor the selected layer.

6. In the New Overviews section, click theResampling type arrow and choose one of thefollowing resampling types:

• Nearest neighbour downsampling• Block averaged downsampling• Block mode downsampling

7. Do one of the following:• Click Number of Levels and choose a level.• Click Overview Decimation Levels and type

a number in the box.

The maximum number of overview levels that canbe created are displayed.

8. Click Run.

The Existing Overviews section shows all overviewsassociated with a layer. The section lists the type ofsampling, the associated number of levels, and theoverview decimation levels.

Deleting raster overviews

You can delete raster overviews associated with a layer.

1. In the Build Raste Overviews dialog box, click theDelete Overviews check box.

2. Click Run.

Linking PCIDSK and other databases

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The Link utility protects source data by creating an emptyPCIDSK database and allowing indirect access toimagery on both GDB-supported and PCIDSK files.

Auxiliary information, such a LUTs or bitmaps aretransferred to the newly created PCIDSK file. Linking filesallows several users to work with data while preservingthe integrity of the source files. You can access dataacross a network or on the same system disk withoutduplicating large files. Imagery is not copied ortransferred; instead, pointers are created to describe thedirectory location and layout of data. Changes are savedto the linked file only.

The link file copies auxiliary information such as LUTs,PCTs, bitmaps, vectors, and georeferencing information.You can link to a remote source file, select a destinationfile, and set overview options.

Source File:The Browse button beside the Source Filebox opens a File Selector dialog box. Use it to select thefile you want to link to.

Destination File:Specifies the new version of thePCIDSK source file. Enter the file name directly in theDestination File box, or click Browse to open the FileSelector dialog box and create a new path and directoryfor the link.

Overview Options: Produces a reduced-resolutionoverview of the imported image. You can choose anoption for creating overviews. You can also choose todisable the overviews.

1. From the File menu, click Utility and then clickLink.

2. In the PCIDSK Link dialog box, click Browse nextto Source file.

3. In the File Selector dialog box, navigate to andselect the source file for linking and click Open.

4. In the PCIDSK Link dialog box, click Browse nextto the Destination file box.

5. In the File Selector dialog box, choose a locationfor your destination file. If necessary, create a newfile folder.

6. Type a file name in the File name box.7. Click Save.8. In the PCIDSK Link dialog box, select an overview

option from the Overview options list box.9. Click Link.

Translating file formats

The Translate utility can translate from one GeoGatewaysupported file format to another or create a new PCIDSKfile from a GeoGateway format using only the layers youspecify. In the Translate File dialog box you selectsimilarly georeferenced source and destination files andthen share layer information between the two files.

After choosing source and destination files you canspecify source layers in the source file to include in thetranslation.

1. From the File menu, click Utility and then clickTranslate.

2. In the Translate (Export) File dialog box, clickBrowse next to the Source file.

3. In the File Selector dialog box, navigate to and

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select the source file and click Open.4. In the Translate (Export) File dialog box, click

Browse next to the Destination file box.5. In the File Selector dialog box, choose a location

for your destination file, type a file name in the Filename box, and click Save.

If necessary, create a new file folder.

6. In the Translate (Export) File dialog box, select theformat you want to use from the Output format listbox.

7. In the Source Layers area, select the data files thatwill make up your destination file from the View listbox.

8. Select an item from the Source Layers list and clickAdd.

You can remove a layer from the DestinationLayers list by selecting it and clicking Remove.

9. Click Translate.

Importing and converting ASCII filesThe Import ASCII Table/Points Wizard can import ASCIIfiles into a project and convert them into vector-pointdata. Table values that combine coordinates with fieldresearch data can be imported to the Attribute Managerspreadsheet and converted into vector-point files that youcan add to a project and open as layers in the view pane.

Using the Import ASCII Table/Points wizard

You can use the Import ASCII Table/Points wizard toimport and convert tabular ASCII data. You can format

your ASCII data the same way you would when using acommon spread sheet application. In the wizard,selecting the Delimited option from the Data Format areaallows you to specify a formatting character for the tablecolumns. You can either select a delimiter or specifyanother delimiter by enabling the Other check box andidentifying the character in the Other box.

The Data PreView area displays an updated version ofinformation. The wizard detects delimiters and fileformats when you open a text file. When you select theFixed Width data format and click Next, the dialog boxallows you to identify the number of characters in acolumn within a fixed width formatted file.

The Import ASCII Table/Points Wizard has three steps1. Import and format delimited or fixed width ASCII

files. When you select a file, you can overwrite anexisting layer or create a new one. The DisplayResult option automatically shows results in theview pane when you have completed the step3 ofthe wizard.

2. Identify delimiters or set field widths beforeconverting your ASCII data into tabular format.TheData Type area allows you to identify how the ASCIIdata is formatted; by a character or fixed width. Inthe Import Options area you can choose to eitherimport all records or specify a range of records toimport.

3. Select data types for the fields in your table andconvert to vector points.

Tabular ASCII data does not require georeferencing to beconverted with the wizard. Degrees, minutes, andseconds are not imported as coordinates but as fields

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only. The wizard imports ASCII files only, but can outputto PCIDSK (.pix) format.

The preview area is similar to the Notepad text editor andallows you to see the ASCII information table before it isformatted.

1. Step 1a. From the File menu, click Utility and then click

Import ASCII Table/Points.b. In the Input area of the Import ASCII

Table/Points Wizard, click Browse.c. In the File Selector dialog box, select an

ACSII-format file and click Open.d. Enable one of the following options:e. Display - vector points are opened in the

view pane and are not saved.f. Save - click Browse next to the File list box

and choose a location for saving the output.

If you want to save your output to a specificlayer within the file, select one from the Layerlist box.

g. Enable the Delimited option in the DataFormat area.

If you want the first line of data displayed as aheader row, enter a number of 1 or higher inthe Header row spin box.

h. Click Next.2. Step 2

a. In the Delimiters area, enable a check boxnext to any correct delimiter type for yourfile.You can see the required delimiter in thepreview area between each record.

The Data preview area changes to a tablewhen you choose the correct option.

b. Click Next.3. Step 3

a. In the Coordinate Fields area, select valuesfrom the X, Y, and Z list boxes.

The remaining inputs for the Projection areaare activated and the Import attributes list isupdated.

b. Enter the projection and bounds information inthe Projection area.

c. Click Finish.

Formating fixed width files

1. With your text file open in Step 1 of the wizard,enable the Fixed width option.

2. Set the number of records and header rows youwant in your converted file.

3. Click Next.4. In the Data preview area, click the # of Characters

column in the Field 1 box and type the number ofcharacters you want to allocate to this field.

5. Press Enter.6. Repeat step 4 and step 5 until all fields are added

and formatted properly.7. Click Next.8. Follow the instructions in Step 3 of the wizard.

Opening data from a remote datasource

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You can open data from an Oracle database, a Webservice, a URL, and through Open Database Connectivity(ODBC) as long as the data formats are compatible withGDB technology.

Focus supports read and write access to Oracle8i andOracle 10g Spatial. For more information, refer to#ORACLE# in Supported File Formats under TechnicalReferences in the Geomatica Help.

A Web service provides access to data published on theservers connected to the Web. You can access any Webmapping service (WMS) or Web feature service (WFS)complying with the OGC Web Mapping or FeatureService specifications, and display the data as a layer inthe Focus project. The data is read-only. For detailsabout the Web services, refer to #Selecting Data fromRemote Data Sources# under Common Utilities in theGeomatica Help and the Geomatica WebServer SuiteInstallation Guide.

ODBC creates a connection between Geomatica and adata source such as Microsoft TM Access. For moreinformation, refer to #ODBC# in Supported File Formatsunder Technical References in the Geomatica Help.

1. From the File menu, click Open.2. In the File Selector dialog box, click Remote Data.

Using undefined image data

You can open undefined or raw image data the sameway you would any other file. In the File Selector dialog

box, locate and select your raw imagery and click Open.

When you open raw images the Raw Imagery FileDefinition dialog box opens automatically, allowing youto define the raw imagery file format. The followingcontrols are available to define data:

Header Bytes

Specifies the number of bytes to allocate for headerinformation. The zero value, indicates that imagery datastarts at the very beginning of the file.

Image Size

defines the X (Pixel) and Y (Line) size of the image file.These should be the full size of the image in the file, evenif you only wish to open a sub-set of the file.

Number of Channels

Indicates the number of channels or planes of image datastored in the file.

Data Interleaving

Indicates how multiple channels of image data areinterleaved. This field is not applicable for one channelimage files. However, single-band data can have bandinterleaving.

PIXEL:

The channels are pixel interleaved. For example, in a

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three-channel file, the values in the file are 123123123...,with the channel values for a given pixel located together.

LINE:

The channels are line interleaved. The data for line 1 ofthe first channel occurs first, followed by the data for line1 of the second channel and line 1 of the third channel.Next is line 2 of the first channel, and so on. For example,in a three-channel file, the values in the file would be (line1) 111...222...333, (line 2) 111...222...333, and so on.

BAND:

The channels are band sequential. All the data for theentire first channel would be first, followed by all the datafor the second channel, and so on.

Data Type:

The set of options to define the type of data.

8-bit Unsigned

The data for each channel are 8-bit, unsigned.

16-bit Unsigned

The data for each channel are 16-bit, unsigned. Valuesrange from 0 to 65535, and are two bytes each.

16-bit Signed

The data for each channel are 16-bit, signed. Valuesrange from -32768 to 32767, and are two bytes each.

32-bit Real

The data for each channel are 32-bit IEEE floating pointnumbers. Each value is 4 bytes long.

Byte Order

options for storing the order of multiple-byte data words.Used for non-8-bit image data only, it can be ignored forfiles containing only 8-bit data.

Least Significant Byte first (LSB)

This order is common on IBM computers with Intel 80 x86 architecture. It is sometimes known as swapped orlittle endian. In LSB order, a 16U-pixel value of 1 wouldbe expressed as two bytes, the first a 1, and the seconda 0.

Most Significant Byte first (MSB)

This is the order common on Sun, IBM, RS/6000, HP,SGI, and Mac systems. It is also known as unswapped,big endian, or Motorola order. In MSB order a 16U-pixelvalue of one would be expressed as two bytes, the first azero, and the second a one. The default selected on thepanel is the byte order of the local system.

• In the Raw Imagery Definition dialog box, clickAccept. A new header file is created with the filename extension .pox.

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The new raw configuration file is an auxiliary file thatcontains layout information for the imagery that youprovide. Focus automatically recognizes the new raw filewithout redefining it.

The following is an example of the file produced for asimple 1000 x 1000 8-bit single-channel image.

Auxiliary Target:

rawimage.bil

Raw Definition:

1000 1000 1

ChanDefinition - 1:

8U 0 1 1000 Swapped

Once the .pox file is created, you cannot define the rawfile again until the .pox file is deleted. Whenexperimenting with possible raw file definitions, an .poxfile is not recommended.

You can work directly with all items in the control paneunder both the Maps and Files tabs. You can rename andremove data whether or not you are working with aproject file.

Image metadata supportMetadata refers to a specific image in a PCIDSK file. All

images and associated metadata are considered imagedata sets. Channels, other than those containing imagedata set bands, can exist in a PCIDSK file. Metadata isnot associated with ancillary raster data or raster mapsproduced from image analysis.

Focus supports image metadata to accommodatehyperspectral processing and analysis through PCIDSKfiles. Image metadata must be formatted as an XMLdocument in a text file. The METAIN program reads themetadata from the XML document and writes it to ametadata segment in the PCIDSK file that contains theassociated image data. Existing metadata is overwritten.The METAOUT program reads metadata from a segmentin the PCIDSK file and formats it as an XML document.

The required format of an image metadata XMLdocument is specified by the XML schema stored in thePCI ImageMetadata.xsd file if the $PCIHOME/etcdirectory of the Geomatica installation CD.

Working with projectionsProjections are required to tie down an image to theearth#s surface. Once the required projection informationhas been defined and the image has been corrected tooverlay the projection bounds, image equirectangularpixel and line coordinates can be transformed to produceequirectangular projection easting and northingcoordinates which can be transformed with the projectionformulas to produce equivalent non-equirectangularlongitude and latitude coordinates. Longitude and latitudecoordinates can also be transformed to projection eastingand northings and image database pixel and line

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coordinates.

Understanding PCIDSK projection definition

Projections can compensate for distortions in large-scaleimagery that cover a large earth surface, wheredistortions are produced from earth curvature. These arethe same distortions that occur in projecting a sphericalsurface (the Earth) onto a flat surface (the imagedatabase). Although there are still distortions in allprojections, some are removed or compensated fordepending on the projection used.

Once an image is tied to one projection, it canautomatically be projected to overlay another projection.This gives you options to process your data by matchinggoals to the appropriate projection.

The software used for the projection transforms is theGeneral Cartographic Transformation Package (GCTP),produced by the U.S. Geological Survey, and can beused to convert:

• projection coordinates to geographic coordinates.• geographic coordinates to projection coordinates.• projection coordinates to coordinates in a second

projection.• Transforms between different earth models is

discussed under the EARTH MODELS sub-topic.

Supported projections

The following table lists the projections supported inFocus. The information for each projection is repeated at

the top of the projection sub-topic in the PROJECTIONsection.

Table 8. Supported Projections

Code Class Name Earth Model

ACEA conic Albers ConicalEqual Area

ellipsoid orsphere

AE azimuthal

AzimuthalEquidistant (orZenithalEquidistant)

sphere

CASS cylindrical Cassini (orCassini-Soldner)

ellipsoid orsphere

EC conicEquidistantConic (or SimpleConic, or Conic)

ellipsoid orsphere

ER cylindrical

Equirectangular(or EquidistantCylindrical, orSimpleCylindrical, orRectangular, orPlate Carree)

sphere

GNO azimuthal Gnomonic (orGnomic) sphere

GOOD pseudo-cylindric

Goode#sHomolosine sphere

GVNP azimuthalGen VertNear-SidePerspective

sphere

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Code Class Name Earth Model

KROV conic Krovak Bessel 1841

LAEA azimuthal

LambertAzimuthalEqual-Area (orZenithalEqual-Area)

sphere

LCC conic LambertConformal Conic

ellipsoid orsphere

LONG/LAT

not aprojection

Longitude/Latitude (orGeographic)

ellipsoid orsphere

MC cylindrical Miller Cylindrical sphere

MER cylindrical Mercator ellipsoid orsphere

MSC modifazimuthal

ModifStereographicConformal (orAlaska Grid)

Clarke 1866(NAD27)

OG azimuthal Orthographic sphere

OM cylindrical

Oblique Mercator(or ObliqueCylindrical, orOrthomorphic, orHotine)

ellipsoid orsphere

PC conic Polyconic ellipsoid orsphere

PS azimuthal PolarStereographic

ellipsoid orsphere

Code Class Name Earth Model

ROB pseudo-cylindric Robinson sphere

RSO cylindrical Rectified SkewOrthomorphic

ellipsoid orsphere

SG azimuthal Stereographic sphere

SIN pseudo-cylindric

Sinusoidal (orSanson-Flamsteed)

sphere

SOM modifcylindric

Space ObliqueMercator

ellipsoid orsphere

SPCSusuallyconic orcylindrical

State PlaneCoordinateSystem

Clarke 1866(NAD27) or GRS1980 (NAD83)

TM cylindricalTransverseMercator (orGauss-Krueger)

ellipsoid orsphere

UPS azimuthal Universal PolarStereographic

ellipsoid orsphere

UTM cylindricalUniversalTransverseMercator

ellipsoid orsphere

VDG miscellaneousVan der Grinten sphere

Defining a new projection

A set of parameters can be specified for projectionssupported as generic and opened using the name of the

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projection set. User-defined projections are shown underthe User Projections tab in the Other Georeference Unitsdialog box. By accepting a user projection, the supportedprojection and the associated parameters are recognized.You can view the parameters for the projection byclicking More after accepting the User Projection that hasbeen selected.

New projections are stored in a text file nameduserproj.txt that may exist either locally or in the$PCIHOME/etc subdirectory, or both. New userprojections may be brought into the system by editinguserproj.txt with a text-editor and adding the parametersfor the projection. A template of the fields supported isincluded in userproj.txt that exists in the etcsub-directory in the comment lines at the top of the file.

When working with new projects, keep these rules inmind:

• Each non-comment line will consist of a fieldidentifier (e.g. ProjectionName) and a value for thefield (e.g. 'UKNatGrid'). There would be one or morespaces separating the field identifier and the fieldvalue. The field identifier and value must fit on oneline. Although the present user projection exampleshave the field identifier first followed by the fieldvalue, the field value followed by the field identifieris also supported.

• Processing for the field identifiers is notcase-sensitive, so it doesn#t matter if upper or lowercase or some combination of the two is used.

• Blank lines are acceptable in the file and will beskipped.

• If a field value has spaces in it, it should be

enclosed in double-quotes. For example,ProjectionDescription 'British National Grid.'

• Comments follow an exclamation mark. If the linebegins with an exclamation mark, the whole line is acomment. Trailing comments in a given line areacceptable.

• Processing for a given projection begins when a'ProjectionName' record is read and ends with thenext 'ProjectionName' record or when the end of thefile is reached. Other than that the order of the otherrecords for the projection does not matter.

• Different projections require different parameters.These fields can be defined for any user-definedprojection set:

ProjectionName:

This is the user-defined name that will be presented forthe projection set. This can be 11 printable characters atmost. For example, ProjectionName 'UKNatGrid.'

ProjectionDescription:

This is the descriptive text to present with theProjectionName. Although there is no maximum size, theProjectionDescription should be short and no more than64 characters. If there are spaces in the description, itshould be enclosed in double-quotes. For example,ProjectionDescription 'British National Grid.'

MapUnits:

These are the actual units of the projection set and wouldcorrespond to the units string built up by using the'Generic Projections'. This can be 16 characters at most.

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For example, you can use either MapUnits 'tm e9' orMapUnits 'TM E009.'

Defining datums and ellipsoids

Ellipsoids:

Using ellipsoids rather than datums is still valid as long asthere are not different horizontal datums involved inreprojecting between different map projections.

If there are different horizontal datums that use the sameellipsoid, datum codes should be used. If ellipsoid codesare used, the software incorrectly assumes that theellipsoid is for the same datum.

The following defaults are provided where there is areprojection involving datum shifts:

• For #E000# (Clarke 1866) or #E008# (GRS 1980):• Areas within Canada, Bulk of Canada: 141 W to 44

W; 49 N to 84 N; Western Ontario: 95 W to 85 W;48 N to 49 N Southern Ontario, West: 85 W to 79W; 42 N to 49 N; Southern Ontario, East: 79 W to74 W; 42d30# N to 49 N; Southern Quebec, West:74 W to 70 W; 45 N to 49 N; Southern Quebec,East: 70 W to 68 W; 47 N to 49 N; Atlantic area: 68W to 44 W; 43 N to 49 N;

• #E000# (Clarke 1866) defaults toand#147;D-03and#148; (NAD27 (Canada, NTv1))

• #E008# (GRS 1980) defaults to #D-04# (NAD83(Canada, NTv1))

• Areas outside Canada,• #E000# (Clarke 1866) defaults to #D-01# (NAD27

(USA, NADCON))• #E008# (GRS 1980) defaults to #D-02# (NAD83

(USA, NADCON))• #E019# (Normal Sphere) defaults to #D800#• #E012# (WGS 84) defaults to #D000#• #E005# (WGS 72) defaults to #D186#

New Ellipsoids

A new ellipsoid not supported at present can be definedby adding an entry in the ellipsoid text file.

To add the definition once so it is globally available to allusers (and if you have write-permission to the file), thenew definition would be added to$PCIHOME/etc/ellips.txt.

Or the new definition may be added to a local copy of thefile. (This would not be globally available to all users.) Atthe operating system level (on a Unix platform in thisexample), you could copy the files as follows:

% cp $PCIHOME/etc/ellips.txt

% chmod 644 ellips.txt

A local copy of ellips.txt will be searched before (and sohas priority over) $PCIHOME/etc/ellips.txt.

To define a new ellipsoid, add the new ellipsoid definitionas one line of text to the ellips.txt file. For example:

#E910#,#ATS77#,6378135.0,6356750.305

Where the fields of the new ellipsoid record are as

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follows:

• E910 - A unique code for the ellipsoid.This would beone that does not already exist in the file. The firstcharacter would be E (or e), for ellipsoid, followedby an integer (maximum of 3 characters).

• ATS77 - A descriptive string for the earth ellipsoid.This descriptive isn#t used at present in thesoftware but a field is expected. An empty characterstring could be used.

• 6378135.0 - The ellipsoid semi-major axis inmeters.

• 6356750.305 - The ellipsoid semi-minor axis inmeters.

If datum shifts are involved, the datum that uses the newellipsoid would have to be defined. To do this see theNEW DATUMS topic.

Reprojecting filesWhen you add new data, it is automatically reprojectedbased on the data you already have open. When youopen large, secondary files of a different projection, theyare also automatically reprojected, which can make thework slower. You may encounter this situation, forexample, when a work file has a UTM projection and youopen a file with an LCC projection. If you open the UTMdata first, Focus must reproject the LCC to UTM. In suchcases, it is recommended that you reproject the datamanually and save it as a new file.

You can reproject both raster and vector data if the datais in a valid projection, it is in a GDB-supported format,and you know which datums were used. A datum is a

mathematical surface used to make geographiccomputations. An ellipsoid defines the dimensions of theearth. The datum includes the ellipsoid used and itsposition relative to the center of the earth.

Each datum references one ellipsoid, but an ellipsoid canbe referenced by one or more datums. If you comparethe position of a point calculated using one datum andthen calculate the same position using a different datum,the coordinates of the point will be different, even if thedatums refer to the same ellipsoid.

Since a datum is a mathematical surface used to makegeographic computations, it is possible to convert fromone datum to another. However, reprojecting a file fromone ellipsoid to another will not provide the correct resultsbecause the critical information contained in a datum isnot defined in the ellipsoid.

About the Reproject dialog box

The Reproject dialog box lets you reproject data. You canselect data, set reprojection bounds, and work withselected layers in the source and destination layers.

Destination files are automatically created in PCIDSKformat. Reprojections can be exported as anyGDB-compatible format.

Browse:

Opens the File Selector dialog box to select source dataor a destination file, depending on the button you click.

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Source Files:

Reports your source files.

Destination Files:

Reports your Destination files.

Output Format

Allows you to choose a GDB file format for your output.

Options:

Lets you enter an option for your output data.

Reprojection bounds

The Reprojection Bounds area allows you to select thecombination of parameters to use for reprojection. It alsolets you add your reprojection information.

Size:

Lets you enter the size of your reprojection bounds inlines and pixels.

Pixels:

Lets you enter the number of pixels for your reprojection.

Lines:

Lets you enter the number of lines for your reprojection.

Pixel Size:

Allows you to set the pixel size along the X and Y axes.

X:

Lets you enter a value for the pixel X size.

Y:

Lets you enter a value for the pixel X size.

Projection Method:

Lets you enter a value for the pixel Y size.

Earth Model:

Lets you select a projection method for your reprojection.

More:

Opens the Earth Models dialog box, where can selectdatums and elipsoids.

Bounds:

Lets you choose either geographic or geocoded boundsmeasurements.

Upper Left:

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Lets you enter either geocoded or geographiccoordinates for the upper-left corner of the reprojection.

Lower Right:

Lets you enter either geocoded or geographiccoordinates for the lower-right corner reprojection.

Pixel Size X:

Reports the size of the X pixels.

Pixel Size Y:

Reports the size of the Y pixels.

Resampling:

Lets you choose a re-sampling method.

Transform Order:

Lets you choose an order of transformation.

Sampling Interval:

Lets you enter a sampling interval value.

Selectable layers and reprojection

The Selectable Layers area allows you to choose thesource and destination layers for the reprojection.

Source Layers:

Lists the layers in your source files.

View:

Lets you choose the data types you want to include in thereprojection.

Select All:

Selects all of the data listed in the Source Layers area.

Add:

Moves the selected layers in the Source Layers area tothe Destination Layers area.

Destination Layers:

Lists the layers that will be included in the reprojection.

Remove:

Removes selected layers form the Destination Layers list.

Select All:

Selects all of the layers listed in the Destination Layerslist.

Reprojection:

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Runs the reprojection.

1. From the Tools menu, click Reprojection.2. In the Reproject dialog box, click Browse next to

the Source file.3. From the File Selector dialog box, locate and select

the file that will provide the projection.4. Click Open.5. Click Browse next to the Destination file box and

select a destination file from the File Selectordialog box.

6. Locate the directory where you want to save thereprojected file.

7. Type a name for your reprojected file in the Filename box.

8. Click Save.

Setting reprojection bounds

Select one of three methods for determining the boundsof the data that is to undergo reprojection.

Pixels/lines and bounds:

Varies the pixel size to create a file with the pixel, lines,and bounds values that you select.

Pixels/lines and resolution:

Varies the bounds based on the resolution of the sourcefile.

Bounds and resolution:

Inputs the file size in pixels and lines, and changes the

pixel size.

You can choose from either geocoded or geographicreprojection bounds.

Geocoded:

Displays the upper-left and lower-right bounds innorthings and eastings.

Geographic:

Displays the upper-left and lower-right bounds in latitudeand longitude.

Specifying a coordinate system

When your imagery has no georeferencing, you can usethe pixels in the raster file as the coordinate system.

1. Select Pixel from the Coordinate System list box.2. From the UTM Zones dialog box, select a zone

from the list.3. Click Accept.4. From the UTM Rows dialog box, select a row from

the list.5. Click Accept.

Selecting an ellipsoidal earth model

The coordinate system defaults to the coordinate systemof the source file. For example, if UTM 11 E000 is thecoordinate system of the source file, UTM 11 refers to

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UTM Zone 11 and E000 is the Ellipsoidal Earth modelE000-Clarke 1866. This is shown in the text box to theright of the Earth Model button.

1. In the Reprojection Bounds area, click EarthModel.

2. In the Earth Models dialog box, click the Ellipsoidstab and select an Earth model.

3. Click Accept.

Selecting the earth model

1. In the Reprojection Bounds area, click EarthModel.

2. In the Earth Models dialog box, click the Datumstab and select an Earth model.

3. Click Accept.

Selecting the SPCS coordinatesystem

1. Choose SPCS from the Coordinate System listbox, to the left of the Earth Model button.

2. From the State Plane Zones dialog box, choose azone.

3. Click Accept.

Selecting a different coordinate system

1. Choose Other from the Coordinate System listbox, to the left of the Earth Model button.

2. From the Other Projections dialog box, click the

Generic Projections tab and choose ageoreferencing unit.

3. Click Accept.4. In the Projection Definition dialog box, type a

longitude in the Longitude column of the TrueOrigin box.

5. Type a latitude in the Latitude column of the TrueOrigin box.

6. Click Accept.

Maximum bounds and resamplingmethodsYou can reset the bounds, using the Maximum Boundscommand, after the output projection has been definedand before using the Reproject command.

The maximum bounds are derived by projecting theupper-left and lower-right corners. The Maximum Boundsfunction can also project 441 points or 21 pixel positionsby 21 scan line positions, distributed over the entire inputimage. You can reset the maximum bounds to theiroriginal values by clicking the Maximum Boundscommand.

The resampling method affects image reprojection only.You can change the resampling method by selecting thenearest neighbour, bilinear interpolation, or cubicconvolution. Bitmaps are automatically resampled usingthe nearest-neighbor method.

You can change the resampling method by opening theResampling list and choosing a method you want to use.Transformations are computed from 256 ground control

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points based on the projection transformation.

Exact Transformation

The default order that performs a calculation for eachpixel in the file.

Polynomial Transformations

As the polynomial order increases, the accuracygenerally increases, but the reprojection processbecomes slower.

Thin Plate Spline Transformation

Is based on fitting splines to the ground control points.The Thin Plate Spline method is more accurate than thepolynomial methods but results in a slower reprojectionprocess.

The transform order approximation is only applied whenreprojecting imagery and bitmaps. The vertices of vectorlayers are transformed exactly. For sampling intervalshigher than one, the reprojected position is calculated atevery sampling interval. A linear interpolation isperformed for the in-between values.

To control the spacing in the calculation of thereprojected position, set the sampling interval from one toa maximum value of four.

Selecting database layers for

reprojection

After specifying your reprojection, you can select thelayers to use for your destination file. You can list layersof a similar type that you wish to work with; for example,you can show all available files in the source list.

1. From the View menu, click BIT Segments.2. In the Source File Layers list, choose a file name

and click Add.

If you want to reposition an item in the DestinationFile Layers list, select it and click the up or downarrow button.

If you want to select the entire list in theDestination File Layers list box, click Select All.

3. Click Reproject.

The reprojected file is not opened in the view pane.You must open the file separately.

Organizing and editing layers

In Focus, geographic features and their attributed dataare stored in layers. Each layer of information can eitherrepresent a single set of geographic information, such ashydrography, or a combination of information features.

In a layer, raster and vector data are stored just likeareas stored in Maps. Layer information can be displayedand can consist of lines, polygons, and symbols thatrepresent project information. You can build a map by

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placing each layer on top of the other. In the Maps tree,each layer appears as a branch belonging to an area.

Layers let you organize and edit the features in a map.You can break a map into multiple layers, eachcontaining a portion of the overall content. Most layertasks are specific to the layer type, but many functionsare common to both image and vector layers.

You can show or hide layers in the Maps tree. To workwith a layer, you must make it active.

Note: You can add new features to the active layer only.A pencil icon indicates the layer is active.

To display a layer

1. In the Maps tree, enable the check box next to alayer.

A check mark next to a vector layer in the Maps treeindicates that the layer is open in the view pane. Ifyou cannot see an open layer, it may be covered byanother layer.

To make a layer active

1. In the Maps tree, select the layer you want toactivate.

A pencil icon indicates the layer is active.

To move a layer

1. In the Maps tree list, drag the layer up or down inthe tree.

A line indicates where the layer will be placed.

To copy a layer

1. In the Maps tree, right-click a layer and click Copy.2. Right-click where you want to paste the layer and

click Paste.

To remove a layer

1. In the Maps tree, right-click a layer remove andclick Remove.

The layer will be removed from the map, but thelayer data is not removed from the data file.

To rename a layer

1. In the Maps tree, right-click a layer and clickRename.

2. Type a new name and press Enter.

Adding and removing imagery

You can create a new layer for your map when you wantto add digitized map information, digitize an image file, orcreate different layers of geographic information.

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You can create a new layer by right-clicking an area iconand using the shortcut menu to add new raster, vector, orbitmap layers. When you create a new layer, you mustset the parameters of the new area.

New layers are automatically rescaled and georeferencedto the area. Any areas with undefined projections use themeter projection by default. You can change the layertype, data type, and the georeferencing when you set upthe layer parameters. When you create a new layer, theparameters describe the amounts and kinds of data youcan use in the layer properties.

Creating a new raster layer

Raster layers are most often used as background forvector-based maps. You can also use raster images forthematic maps. In the Maps tree, image layers arealways a sub-level of an area. You can use several typesof image files. The table below shows a list of supportedimage file types with a description of each.

Table 9.

Data Type Description

8-bit Pixel values 0 to 255

16-bit Signed Pixel values -32,768 to32,767

16-bit Unsigned Pixel values 0 to 65,535

32-bit Real Pixel values - 1.2x1038 to3.4x1038

1. In the Maps tree, right-click an area and click NewRaster Layer.

2. In the New Raster Layer dialog box, enable anoption in the Layer Type area.

3. In the Data Type area, enable an option for the datatype you want.

4. Enable an option in the Georeferencing area andfill in the appropriate information.

5. Click OK.

Creating a new bitmap layer

In Focus, a bitmap layer acts as a graphical layer thatcan be used to mask regions in your imagery for a varietyof purposes. You can create a new empty bitmap layerwhen you want to work with raster information in a layerof lower priority.

1. In the Maps tree, right-click an area and click NewBitmap Layer.

2. In the New Bitmap dialog box, enable aGeoreferencing option and fill in the appropriateinformation.

3. Click OK.

Creating a new vector layer

You can create a new empty vector layer when you wantto use digitized map information, break your map intodifferent layers with specific geographical information, orwhen you want to create vectors on top of an image inthe view pane.

1. In the Maps tree, right-click an area and click New

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Vector Layer.2. In the New Vector Layer dialog box, enable a

Layer Type option.3. Enable a Georeferencing option and fill in the

appropriate information.4. Click OK.

Setting vector layer attributes

Layer data, such as symbols, lines, filled areas, polygons,and text, are stored and categorized separately inRepCodes. The RepCode defines each feature by a setof coordinates and descriptive labels. The features areshown as a layer within an area.

Each map element requires its own RepCode. RepCodesalso link the vector files to the RST, and tell the systemhow to show each feature on the screen.

The View Attributes dialog box is a spreadsheet forvector layer information.You can use it to view and editpoint data in vector files, and to work with RepCodes.

To view vector properties

1. In the Maps tree, right-click a vector and clickProperties.

To view vector attributes

1. In the Maps tree, right-click a vector and clickAttribute Manager.

To change the magnification of the preview image,click the zoom commands below the Preview area.

Setting vector layer properties

General vector layer properties define how the layer isdisplayed on screen.

To set up general vector layer properties

1. In the Maps tree, right-click a vector layer and clickProperties.

2. In the Vector Layer Properties dialog box, click theGeneral tab.

3. In the Description field, enter a description of thelayer.

4. Enable or disable any of the following check boxes:• Read Only: enabling this option prevents the

vector layer from being changed.• Visible: enabling this option makes the layer

visible in the view pane.5. Enter a value that represents the layer priority in the

Priority box.

Layer priority may cause one layer to mask anotherin the Maps tree. If you cannot see a layer in yourmap, check the layer priority. Changing layer priorityis necessary to present a vector layer over a rasterlayer or a bitmap layer.

6. Click OK.

You can save a vector layer as part of a .pix file thatcontains your work or as part of a project file.

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To save a vector layer

1. In the Maps tree, right-click a layer and click Save.2. In the New Layer Detected dialog box, choose the

Output File, the file format and, if applicable, thechannels you want to save.

3. Click Save.

Transferring layers

You can transfer layers by copying them from a sourcefile and saving them to a destination file. The transferreddata can either be added on to a new layer or overwrittenin the destination file.

For example, you can specify that a PCT segment in thesource file be added as a new segment in the destinationfile or you can specify that a PCT segment is overwrittenin a destination file. The source file is never modifiedwhen it is transferred; however, the destination file isalways changed.

You can transfer any GDB-supported files. Somenon-PCIDSK file formats may not be compatible.Georeferencing cannot be transferred between files.Input imagery is changed to match the destination filedimensions.

Use the Transfer Layers dialog box to select similarlygeoreferenced source and destination files and to sharelayer information between the two files.

Source File:

Opens the File Selector dialog box where you can selecta file with the layers you want to copy.

Destination File:

Opens the File Selector dialog box where you can selecta file to receive the data layers.

Source Layers:

Shows a complete list of all channels, bitmaps, andvectors in the source file. You can choose the layers youwant to copy to the destination file, list layers by type inthe list window, or you can select all.

Destination Layers:

Shows a list of all channels, bitmaps, vectors in thedestination file. Source layers that you have chosen toadd or overwrite also appear in this list. Click the Removeand Select Transferred command buttons if you want toundo transfer relationships.

1. From the File menu, click Utility and then clickTransfer Layers.

2. In the Transfer Layers dialog box, click Browsenext to the source file.

3. In the File Selector dialog box, locate the file withthe data you want to transfer and click Open.

4. Click Browse next to the destination file and locatethe file to where you want to transfer your layers.

5. Click Save.

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6. Choose a layer type from the View list box.7. Select the layers that you want to transfer and click

Add.8. Click Transfer Layers.

Working with data toolsFocus has tools designed to help you produce new filesfrom your existing data. You can create new data files bysaving existing files as other formats. You can also clipimages to produce new files and you can create subsetfiles that maintain the attributes of the original data.

Changing data formatsYou can convert several file types to different formats bysaving them as the format you want directly from theMaps tree.

The following files types can be converted:

• Bitmap• Greyscale• RGB• RST• SYM• PCT

About the Bitmap Save As dialog box

The bitmap Save As dialog box allows you to save abitmap from the Maps tree. You can save the file to alayer within the target file or to a new layer. In the Mapstree, bitmaps are listed whether they are saved or not. Inthe Files tree, however, bitmaps are listed only if they are

saved. For each saved bitmap, both the file and layernames are displayed.

Input:

The Input section displays the name of the layer and thedata type that you are about to save.

Output:

The Output section allows you to choose the target fileand format in which you want to save the bitmap. Youcan also select a layer within the target file or create alayer for the bitmap.

File:

The File list allows you to select the file in which you wantto save the bitmap. If the file is not listed, you can browseand select the file.

Format:

The Format list allows you to select the format in whichyou want to save the bitmap.

Options:

The Options button opens the GDB Options dialog box.(See Selecting GDB format options on page 145 )

Layer:

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The Layer list allows you to select a layer within thetarget file or create a layer for the bitmap.

About the Vector Save As dialog box

The Vector Save As dialog box lets you save a vectorlayer from the Maps tree as another file format. You cansave the file to the original layer or to a new layer.

Input:

Reports the location of the layer and the data type withwhich you are working.

Layer:

Reports the layer type for the current layer.

Save selected shapes only:

Saves only the shapes you have selected in the viewpane or the Attribute Manager. When no shapes areselected, the option is disabled. If you have shapesselected and you want to overwrite the original segment,the option is disabled.

Save selected fields only:

Saves only the selected fields. When no fields areselected, the option is not available.

Output:

Lets you choose a target file for saving your new vectordata, select a format for the new data, and choose orcreate a layer within your target file.

File:

Lets you select a target file for your new vector data froma list.

Browse:

Opens the File Selector dialog box, letting you choose adifferent target file, not showing in the File list.

Format:

Lets you choose an output format from the list ofavailable formats.

Options:

Opens the GDB Options Editor. (See Selecting GDBformat options on page 145 )

Layer:

Lets you choose a target layer from a list of layers. Youcan also choose to save your new file to a new layer.

Selecting GDB format options

The GDB Options Editor lets you configure the GDBformat you have chosen for your output. Some of the

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GDB formats do not have data type options.

1. Click the Options button.2. In the GDB Options Editor, choose any of the file

options you want for your output data. For moreinformation about the specific option for the selectedfile format, click the Help button on the GDBOptions Editor.

3. Click OK.

About the Grayscale Save As dialog box

The Grayscale Save As dialog box lets you save abitmap from the Maps tree in another file format. You cansave the file to the original layer or to a new layer.

Input:

Reports the location of the layer and the data type withwhich you are working.

Layer:

Reports the layer type for the current layer.

Raster with attribute data:

Saves the raster and its associated attribute table.

Raster only:

Saves only the raster data.

Save selected shapes only:

Saves only the records that you have selected in theAttribute Manager. When no records are selected, theoption is not available.

Save selected fields only:

Saves only the fields that you have selected in theAttribute Manager. When no fields are selected, theoption is not available.

Output:

Lets you choose a target file for saving the layer, select aformat for the new file, and choose or create a layerwithin your target file.

File:

Lets you select a target file for your new layer. TheBrowse button lets you choose a file not showing in theFile list.

Format:

Lets you choose an output format from the list ofavailable formats.

Options:

Opens the GDB Options editor. (See Selecting GDBformat options on page 145 )

Layer:

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Lets you choose a target layer from the list of layers. Youcan also choose to save your new file to a new layer.

Properties:

Opens the Output Layer Properties dialog box.

About the Output Layer Properties dialogbox

The Output Layer Properties dialog box lets you set theproperties for your new output layers when you convert afile to another GDB-supported format. You can select anoutput type, change the layer scaling, and save originalfile enhancements as an LUT.

Output Type:

Lets you change the bit depth for your output file bychoosing from a list of available bit depth values. Forexample, 8-bit, 16-bit, or 32-bit, depending on the valuesshown in the list.

Scaling:

Lets you choose a scaling method for your output file.(See Scaling images on page 257 )

Enhancement:

Lets you choose and set a default LUT.

Output Lookup Table:

Lets you select an available LUT and gives you theoption to have no LUT for your file or to save an LUT as anew layer.

Save as default look-up table:

Lets you choose to assign an LUT as the file default.

About the PCT Output Layer Propertiesdialog box

The Output Layer Properties dialog box lets you save thecolor table with the PCT layer.

Output Color Table:

Lets you save the PCT color table as a new layer.

Save as default look-up table:

Lets you choose to assign the color table as the file#sdefault.

About the RST Save As dialog box

The RST Save As dialog box lets you save a copy of anRST file from the Maps tree to another target file. Youcan save the file to the original layer or to a new layer.

Input:

Reports the location of the RST file with which you areworking.

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Output:

Lets you choose a target file for saving your new bitmap,Select a format for the new file and choose or create alayer within your target file.

File:

Lets you select a target file for your new bitmap. TheBrowse button lets you choose a file not showing in theFile list.

Browse:

Opens the File Selector dialog box.

Format:

Lets you choose an output format from the list ofavailable formats.

Description:

Lets you change the name of the saved RST.

About the RGB Save As dialog box

The RGB Save As dialog box lets you save an RGB filein the Maps tree to another file format. You can save thefile to the original layer or to a new layer. You can alsoselect channels and change channel properties.

Input:

Reports the location of the layer and the data type withwhich you are working.

Output:

Lets you choose a target file for saving your new RGBfile, select a format for the new file, and choose or createa new layer within your target file.

File:

Lets you select a target file for your new RGB file. TheBrowse button lets you browse for a file not shown in theFile list.

Browse:

Opens a File Selector panel so you can choose a targetfile at a different location.

Format:

Lets you choose an output format from the list ofavailable formats.

Options:

Opens the GDB Options Editor.

Layer:

Lets you choose a target layer from the list of layers. Youcan also choose to save your new file to a new layer.

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There are three of these list boxes

Properties:

Opens the Output Layer Properties dialog box. There arethree of these buttons.

About the PCT Save As dialog box

The PCT Save As dialog box lets you save a PCTsegment in the Maps tree as a PCIDSK (.pix) file.

If you are saving a layer containing a map from a Webmapping service to your local drive, you must also saveits color table or the map may not have the samerepresentation the next time you open it. To save thecolor table, click Properties.

Input:

Reports the location of the layer and the data type withwhich you are working.

Layer:

Reports the layer description for the current layer.

Raster with attribute data:

If the layer contains attributes, the Raster with attributedata option becomes available. When it is clicked, theraster and its associated attribute table is saved to thefile.

Raster only:

If the layer contains attributes, the Raster only optionbecomes available. When it is clicked, the raster data issaved without the attribute data.

Save selected shapes only:

If the layer contains attributes and shapes are selected,the Save selected shapes only option is available. Whenit is enabled, only the records that you have selected inthe Attribute Manager are saved in the file. If you haveshapes selected and you want to overwrite the originalsegment, the option is disabled.

Save selected fields only:

If the layer contains attributes and fields are selected, theSave selected fields only option is available. When it isenabled, only the fields that you have selected in theAttribute Manager are saved in the file.

Output:

Lets you choose a target file for saving the layer and letsyou choose or create a new layer within your target file.

File:

Lets you select a target file for your new layer.

Browse:

Opens the File Selector dialog box, where you can

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browse for a file not shown in the File list.

Format:

Contains only the PCIDSK format.

Options:

Opens the GDB Options Editor. (See Selecting GDBformat options on page 145 )

Layer:

Lets you choose a target layer from the list of layers. Youcan also choose to save to a new layer.

Properties:

Opens the Output Layer Properties dialog box.

About the LUT Save As dialog box

The LUT Save As dialog box lets you save a lookup table(LUT) in a file.

Input:

Reports the LUT with which you are working.

Layer:

Reports the LUT for the current layer.

Raster with attribute data:

If you are saving the image with the LUT and the layercontains attributes, the Raster with attribute data optionbecomes available. When it is clicked, the raster and itsassociated attribute table is saved to the file.

Raster only:

If you are saving the image with the LUT and the layercontains attributes, the Raster only option becomesavailable. When it is clicked, the raster data is savedwithout the attribute data.

Save selected shapes only:

If you are saving the image with the LUT and the layercontains attributes and shapes are selected, the Saveselected shapes only option is available. When it isenabled, only the records that you have selected in theAttribute Manager are saved in the file.

Save selected fields only:

If you are saving the image with the LUT and the layercontains attributes and fields are selected, the Saveselected fields only option is available. When it isenabled, only the fields that you have selected in theAttribute Manager are saved in the file.

Output:

Lets you choose a target file for saving the LUT, select aformat for the file, and choose or create a new layer

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within your target file.

File:

Lets you select a target file for your LUT segment.

Browse:

Opens the File Selector dialog box, where you canbrowse for a file not shown in the File list.

Format:

Lets you choose an output format from a list of availableformats.

Options:

Opens the GDB Options Editor. (See Selecting GDBformat options on page 145 )

Layer:

Lets you choose a target layer from the list of layers. Youcan also choose to save your LUT to a new layer.

Properties:

Opens the Output Layer Properties dialog box.

Opening the Clipping/Subsettingpanel

Clipping and subsetting data are effective methodsworking with large data sets. In research and testingsituations, you may want to create subsets of a large database. By working with small representative areas, youcan reduce processing times or you can use file subsetsto test an image process. When you obtain a promisingresult on a subset, you can repeat the process on alarger, more complex scene.

Before creating a subset or a clip, you should considerthe output format. A subset file is based on the file type ofthe source file by default. You can change the outputformat of a subset to any GDB-compatible data type. Forsome file types you may want to add or removeinformation. The Clipping/Subsetting process lets youchoose the file data type for a clip or subset with the GDBOptions Editor.

When you have selected a file, you can work with theAvailable Layers list. The list of layers depends on theoutput format you have chosen. For example, if youselect a format that only supports vector data (forexample, SHP format), only vector layers are listed.

Note: If vector georeferences are not compatible with thesource file, vectors in the segment are not clipped. Awarning message shows a list of incompatible vectorsegments. Georeferencing is compatible when they areequal, or when one is an under specified form of theother.

• From the Tools menu, click Clipping/Subsetting.

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Clipping and subsetting images

When using the Clipping/Subsetting feature, you mustspecify the bounds of a clip or subset and then run theprocess. For more information, see Opening theClipping/Subsetting panel on page 151 .

1. From the Clipping/Subsetting dialog box, choosea file from the File list box in the Input area.

If the file is not listed, click Browse and choose afile from the File Selector dialog box.

2. Enable the layers that you want to clip from theAvailable Layers list.

• A check mark indicates the layers that will beclipped.

3. In the Output area, choose a file from the File listbox.

• If the file is not listed, click Browse andchoose a file from the File Selector dialogbox.

• If you want to use the Select a Script SubsetFile Definition Method, you can leave the Filebox empty.

4. Select the file format that you want for the outputfrom the Format list box.

If you want to select specific options for the format,click Options and select options from the GDBOptions Editor.

5. Enter a value that you want to use for pixels withoutdata in the output file in the Initialization Value spinbox. Use a value that does not occur in the imagebeing clipped.

If you want to give the initialization value themetadata tag of no data, enable the Set as No DataValue check box.

6. If you want to save the defined clip region boundaryas a vector layer in the output file, enable theOutput Clip Boundary Vector check box.

7. Depending on how you want to use to clip theimage, select one of the following options from theDefinition Method list box:

• User-entered Coordinates: enters the cornercoordinates for the clip region. All layers willbe clipped to fit that region. See Defining theclip region with user-entered coordinates onpage 153 .

• Select a File: uses a smaller, intersecting fileto define the bounds of a subset. See Definingthe clip region by selecting a file on page 153 .

• Select a Clip Layer: uses a smaller,intersecting layer from a file to define thebounds of a subset. See Defining the clipregion by selecting a layer on page 154 .

• Select a Named Region: bases the clip on anamed region you created in Focus. SeeDefining the clip region by selecting a namedregion on page 154 .

• Select a Script Subset File: creates severalclip regions on the same image. You cancreate a text file containing the coordinatesand the output file name; Focus automaticallyproduces the series of subset files. SeeDefining the clip region by selecting a scriptsubset file on page 154 .

• Use Current View: bases the clip on theregion displayed in the view pane. Only

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available from Area view. See Defining the clipregion using the Zoom tools on page 158 .

8. Click Clip.

Defining the clip region with user-enteredcoordinates

You can define the clip region by manually enteringcoordinates for the exact area of the data you want tosave as a subset. The following procedures follow step 7in Clipping and subsetting images on page 152 .

To set the clip region

1. In the Definition Method list box, chooseUser-entered Coordinates.

2. In the Coordinate Type list box, choose one of thefollowing formats to define the coordinates for theclip region:

• Raster extents: defines the clip region byidentifying upper-left and lower-right pixel andline coordinates.

• Geocoded extents: defines the clip region byidentifying the georeferenced coordinates ofthe upper-left and lower-right corners.

• Long/Lat extents: defines the clip region byidentifying the geographic coordinates of theupper-left and lower-right corners.

• Raster offset/size: defines the clip region byidentifying the pixel and line coordinates of theupper-left corner and providing the number ofpixels in width and the number of line inlength.

• Geocoded offset/size: defines the clip regionby identifying the georeferenced coordinatesof the upper-left corner and providing widthand length in the units of measurement of theinput coordinate system.

3. In the Upper Left boxes, type the coordinates forthe top-left corner of the clip region.

• If you selected Raster extents, Geocodedextents, or Long/Lat extents from theCoordinate Type list box, type thecoordinates for the bottom-right corner of theclip region in the Lower Right boxes.

• If you selected Raster offset/size from theCoordinate Type list box, type a valuerepresenting the number of pixels in the Widthbox and type a value representing the numberof lines that you want to form the clip region inthe Height box.

• If you selected Geocoded offset/size from theCoordinate Type list box, identify the size ofthe clip region. Using the measurement unit ofthe projection, type the distance for the widthin the Width box and type the distance for theheight in the Height box.

4. Click Clip.

To change a clip area with the bounding outline

1. In the Preview area, drag a bounding outline corneruntil you have the size you want.

2. Drag the bounding outline to a new location.3. Click Clip.

Defining the clip region by selecting a file

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You can use a smaller intersecting file to define thebounds of a subset. The Select a File Method requirestwo files. You use one file as input and the other to definethe subset. The definition file must be smaller than thesource file. The following procedures follow step 7 inClipping and subsetting images on page 152 .

1. In the Define Clip Region area, choose Select aFile from the Definition Method list box.

2. Choose a file from the File list box.

If the file is not listed, click Browse and choose afile from the File Selector dialog box.

3. Click Clip.

Defining the clip region by selecting a layer

You can also use a smaller intersecting layer to definethe bounds of a subset. The Select a Clip Layer methodworks the same way as the Select a file method. You canuse one layer as input and another layer to define thesubset. The definition layer must be smaller than thesource layer. The following procedures follow step 7 inClipping and subsetting images on page 152 .

1. In the Define Clip Region area, choose Select aClip Layer from the Definition Method list box.

2. Choose a file that you want to use as the clip regionfrom the File list box.

If the file is not listed, click Browse and choose afile from the File Selector dialog box.

3. Choose a layer from the Layer list box.

If the layer contains vectors, you can use only the

selected shapes in the layer to define the clipregion. To use only the selected shapes, enable theClip using selected shapes only check box.

4. Enable one of the following options:• Extents: uses the rectangular extents of the

vectors as the clip region.• Shape(s) Boundary: uses the actual area

covered by the vectors as the clip region.5. Click Clip.

Defining the clip region by selecting anamed region

You can use the bounds of a named region to define asubset clip. You must have at least one named region inthe source data to use this method. Named regions canonly be saved as Geomatica Project (.gpr) files. Thefollowing procedures follow step 7 in Clipping andsubsetting images on page 152 .

1. In the Define Clip Region area, choose Select aNamed Region from the Definition Method listbox.

2. Choose a named region from the Named Regionlist box.

3. Click Clip.

Defining the clip region by selecting a scriptsubset file

You can create several clip regions on the same image.When you create a text file containing the coordinatesand the output file name, Focus automatically produces

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the series of subset files. For more information, seeCreating the text file for Script Subset File method onpage 155 .

The following procedures follow step 7 in Clipping andsubsetting images on page 152 .

1. In the Define Clip Region area, choose Select aScript Subset File from the Definition Method listbox.

2. Choose one of the following formats from theCoordinate Type list box:

• Raster extents: if the clip region is defined byidentifying upper-left and lower-right pixel andline coordinates.

• Geocoded extents: if the clip region isdefined by identifying the georeferencedcoordinates of the upper-left and lower-rightcorners.

• Long/Lat extents: if the clip region is definedby identifying the geographic coordinates ofthe upper-left and lower-right corners.

• Raster offset/size: if the clip region is definedby identifying the pixel and line coordinates ofthe upper-left corner and providing the numberof pixels in width and the number of line inlength.

• Geocoded offset/size: if the clip region isdefined by identifying the georeferencedcoordinates of the upper-left corner andproviding width and length in the units ofmeasurement of the input#s coordinatesystem.

3. Choose the text file containing the coordinates andthe output file names from the File list box.

If the file is not listed, click Browse and choose afile from the File Selector dialog box.

4. Click Clip.

You can verify for errors in the Focus MessageCenter.

Creating the text file for the Script SubsetFile method

You can create several clip regions from one file by usingthe Script Subset File method. With this method youcreate a text file containing the bounds of the clip regionsand list the output file names for each clip. Focus usesthe text file to automatically produce separate filescontaining the subset of the data.

When you create the text file, you need to define thebounds of the clip regions and the file names using aparticular format, depending on what you selected in theCoordinate Type box on the Clipping/Subsetting dialogbox and which file format is selected in the Format boxunder Output (see Clipping and subsetting images onpage 152 ). Each line in the text file contains the data forone clip region. The line is divided into fields separatedby spaces. Each field contains a piece of informationabout the size of the clip region and where to save thefile.

Raster extents:

The clip region is defined by identifying upper-left andlower-right pixel and line coordinates. The format for

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listing the pixel and line coordinates and the file name isas follows:

ul_x ul_y lr_x lr_y path and filename

Where:

ul_x is the pixel coordinate for the upper-left corner of theclip region

ul_y is the line coordinate for the upper-left corner of theclip region

lr_x is the pixel coordinate for the lower-right corner of theclip region

lr_y is the line coordinate for the lower-right corner of theclip region

For example:

82 115 254 302 C:\Clip1.pix

23 56 87 123 C:\Clip2.pix

Geocoded extents

The clip region is defined by identifying thegeoreferenced coordinates of the upper-left andlower-right corners.

ul_x ul_y lr_x lr_y path and filename

Where:

ul_x is the x coordinate for the upper-left corner of the clipregion using the same projection as the input file

ul_y is the y coordinate for the upper-left corner of the clipregion using the same projection as the input file

lr_x is the x coordinate for the lower-right corner of theclip region using the same projection as the input file

lr_y is the y coordinate for the lower-right corner of theclip region using the same projection as the input file

For example:

433000.000 5876000.000 443000.000 5873000.000C:\Clip1.pix

432567.973 5876348.000 435685.342 5874343.341C:\Clip2.pix

Long/Lat extents:

The clip region is defined by identifying the geographiccoordinates of the upper-left and lower-right corners. Theextents can be defined suing a number of differentformats such as the following example. For moreinformation, see the online help for LONG/LAT INPUTunder Projection Reference in the Technical Reference.

ul_x ul_y lr_x lr_y path and filename

Where:

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ul_x is the longitude value for the upper-left corner of theclip region

ul_y is the latitude value for the upper-left corner of theclip region

lr_x is the longitude value for the lower-right corner of theclip region

lr_y is the latitude value for the lower-right corner of theclip region

For example:

117d46'10"W 33d44'55"N 117d40'10"W 33d38'55"NC:\Clip1.pix

117d35'22"W 33d40'30"N 117d30'22"W 33d33'30"NC:\Clip2.pix

Raster offset/size:

The clip region is defined by identifying the pixel and linecoordinates of the upper-left corner and providing thenumber of pixels in width and the number of line inlength.

ul_x ul_y width height path and filename

Where:

ul_x is the pixel coordinate for the upper-left corner of theclip region

ul_y is the line coordinate for the upper-left corner of theclip region

width is the number of pixels from the upper-left corner tothe upper-right corner of the clip region

height is the number of lines from the upper-left corner tothe lower-left corner of the clip region

For example

34 56 400 400 C:\Clip1.pix

135 127 300 100 C:\Clip2.pix

Geocoded offset/size:

The clip region is defined by identifying thegeoreferenced coordinates of the upper-left corner andproviding width and length in the units of measurement ofthe input's coordinate system.

ul_x ul_y width height path and filename

Where:

ul_x is the x coordinate for the upper-left corner of the clipregion using the same projection as the input file

ul_y is the y coordinate for the upper-left corner of the clipregion using the same projection as the input file

width is the distance from the upper-left corner to the

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upper-right corner of the clip region.

height is the distance from the upper-left corner to thelower-left corner of the clip region.

For example:

433000.000 5876000.000 300.000 300.000 C:\Clip1.pix

32567.973 5876348.000 1500.000 2500.000 C:\Clip2.pix

Defining the clip region using the Zoomtools

You create your clip from the region displayed in the viewpane. It is only available in Area view mode. Thefollowing procedures follow step 7 in Clipping andsubsetting images on page 152 .

1. Open the file that you want to clip.2. From the View menu, click Area View Mode.3. Use the zoom tools to display the area that you

want to clip in the view pane.4. From the Tools menu, click Clipping/Subsetting.5. In the Define Clip Region area of the

Clipping/Subsetting dialog box, choose UseCurrent View from the Definition Method list box.

6. Click Clip.

Creating multiple subset tiles

You can create multiple subset files using the tilingfeature on the Clipping/Subsetting dialog box. In the

Clipping/Subsetting dialog box preview window, thebounding outline is replaced by a grid to help you dividethe data into the number and size of tiles you want. Afteryou have selected and prepared the data you want towork with, you access the tile output controls by clickingthe Tile Output command button. You can choose fromtwo tiling methods and you can control the amount ofoverlap between each file. When you process the data,Focus creates a new file based on each tile and the inputdata you selected.

1. In the Clipping/Subsetting dialog box, click TileOutput.

2. In the Tile Definition area, choose one of thefollowing options from the Definition Method listbox:

• Use tile size and overlap:creates tiles basedon the size measurement values that youenter in the Tile Size X and Y boxes.

• Use number of tiles and overlap: createstiles based on the values you enter in theNumber of Tiles X and Y boxes.

3. Choose a unit of measure from the Units list box.

The Geocoded option derives the tile coordinatesfrom the input data.

You can move and re-size the tile bounding grid toany location within the preview window.

4. Enter values that represent the amount of overlapyou want between each of your subset files in theOverlap X and Y boxes.

5. Click Clip.

Selecting a clip region

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A clip region focuses attention on a location by hiding therest of the area from view. The concealed areas remainavailable and are included in any processes that youemploy. You can create a subset or clip of the data. (SeeOpening the Clipping/Subsetting panel on page 151 )

1. Open the Clipping Layer list and choose the layerthat you want to use to define the extents of the clipregion.

If you want to view only the selected shapes, enablethe Clip using selected shapes only check box.

2. Click OK.

Opening the Data Merge wizard

You can combine a group of files, regardless of bounds,projection, data type, or resolution into a single output filewith the Data Merge Wizard. When you start the DataMerge Wizard, follow the instructions at the top of thewizard dialog boxes for each step. The followinginformation gives an outline of how to add information toeach of the Data Merge Wizard dialog boxes.

If a layer does not have a proper projection, it will not beavailable; however, LUT, PCT, and GCP layers can betransferred even if the source files have nogeoreferencing. A warning message opens whengeoreferencing is not compatible. The Data MergeWizard has three steps: choosing input layers, setting theoutput and georeferencing, and setting up output layers.

• From the Tools menu, click Data Merge.

Choosing an input layer

1. In the Data Merge Wizard, click Browse.2. In the File Selector dialog box, select the file you

want to add and click Open.

If you want to view the properties of a file, right-clickthe file in the Available Files/Layers list and clickProperties.

3. In the Available Files/Layers list, enable a checkmark next to any layer that you want to add as aninput layer.

4. Click Next.

Naming the output file

In this step, you can set the georeferencing andreprojection parameters for the output. You can select anew or existing file to receive the merged layers. Youmust first name the file that will receive the merged datalayers in the name box.

1. Choose a file and path from the Name list box.

If the file is not listed, click Browse and choose afile from the File Selector dialog box.

Existing files are not overwritten. The merged datais added to an existing file.

2. Choose an output file format from the Outputformat list box.

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For information on format options, click the ? buttonnext to the Options box.

When merged results are written to existing files,associated georeferencing parameter fields are notavailable in step 2 of the Data Merge Wizard.

3. In the Georeferencing Setup area, set thefollowing items:

• Projection: You can get the maprepresentation, assigned to the output file,from an existing file by selecting a file option oryou can manually enter it.

• Extents: Are the upper-left and lower-rightcorner coordinates of the output file. Thebounds can be based on an existing file,derived from either the union or intersectionboundaries of all the input file, or it can beentered manually.

• Union: Output file extents are large enough toinclude all input file extents. No data iscropped.

• Intersection: The output file extents arebased upon the region of overlap for all inputfiles.

• Resolution: Pixel dimensions can be basedon an existing file or can be entered manually.

• Reprojection Parameters have the followingsettings:

• Resampling: Bitmaps are automaticallyresampled using the nearest-neighbor,bilinear-interpolation, and cubic-convolutionmethods.

• Transform Order: You can choose fromExact, Thin Plate Spline, and 1st Order to

5th Order polynomial transformations. Eachpixel in a file is included in the calculation.

• Sampling Interval: For sampling intervalshigher than 1, the reprojected position iscalculated at each interval. A linearinterpolation is performed for the values inbetween.

4. Click Next.

Setting up output layers

Focus checks each of the input layers for inconsistenciesin format and file projection. When inconsistencies aredetected, a warning message appears. All inappropriatelayers are ignored in the merge process.

You can change the following layer attributes:

Processing Order:

The layer order you see in Step 3 of the wizard is theorder in which layers are merged to the output file. Bydefault, the order is what was selected in the ChooseInput Layers step. To change the order, drag a layer upor down the list.

Rename:

To rename a layer, right-click the layer and click Rename.

Remove:

To remove a layer, right-click the layer and click Remove.

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Set Parameters:

To edit parameters, double-click a layer in the SelectLayer(s) list. A parameters dialog box opens for theselected data type.

• Click Finish.

Data Merge wizard - Set BitmapParameters dialog boxYou can change the parameters for any data type in thefile tree.

You can change several parameters for the outputbitmap. You can identify the source file and layer, selecta target layer or create a new one, and adjust both theorder of transformation and sample interval.

Input File:

Reports the input bitmap you are working with.

Input Layer:

Reports the output layer where your input bitmap islocated.

Output Layer:

Allows you to choose an existing output layer or to createa new one.

Transform Order:

Lets you choose a different transformation order for thebitmap output.

The following transformation orders are available:

• Exact• Thin Plate Spline• 1st order• 2nd order• 3rd order• 4th order• 5th order

Sampling Interval:

Allows you to change the sampling interval for the bitmapfile.

Data Merge wizard - Set Image Parametersdialog box

You can change the parameters for any data type in thefile tree.

You can change several parameters for the outputbitmap. You can identify the source file and layer, selecta target layer or create a new one, and adjust both theorder of transformation and sample interval.

Input File:

Reports the input image you are working with.

Input Layer:

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Reports the output layer where your input image islocated.

Output Layer:

Allows you to choose an existing output layer or to createa new one.

No Data Value:

Lets you use a no-data value parameter in your outputimage file.

Output Type:

Lets you choose a bit-depth for your image output file.

These output types are available:

• 8-bit unsigned• 16-bit signed• 16-bit unsigned• 32-bit

Scaling Function:

Lets you choose a scaling function for your output file.(See Available scaling methods on page 258 )

Resampling:

Lets you choose a resampling method for your mergedoutput. (See Maximum bounds and resampling methodson page 138 )

Transform Order:

Allows you to choose an order of transformation for yourmerged output.

Sampling Interval:

Allows you to change the sampling interval for themerged output.

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Chapter 4Opening the Algorithm LibrarianThe Algorithm Library contains a set of predefined anduser-defined programs that are organized in a treestructure. You can expand a category in the tree the wayyou would any other Windows application by clicking onthe + next to a folder. When you expand a category or asub-category, the items inside each folder are arrangedin alphabetical order. Some folders contain sub-foldersand some contain only a list of algorithms.

The Algorithm Librarian dialog box allows you to searchthe algorithm directory tree. You can also create yourown user-defined category folders to hold the algorithmsthat you use most often. (See Algorithm categories onpage 164 andCreating user-defined categories on page 167).

• From the Tools menu, click Algorithm Librarian.

You can search through the categories within each folderusing the Find utility or you can browse through thecategories based on the directory topics found in eachfolder. (See Finding an algorithm on page 166 )

About the Algorithm Librarian dialog

boxThe Algorithm Librarian dialog box lets you work with theAlgorithm Library. You can search the library and open aModule Control Panel (MCP) for the algorithms you wantto use. (See Working with an algorithm MCP on page 170 )

Algorithm Library:

Lists algorithms in a directory tree in the Algorithm Librarypane on the left side of the Algorithm Librarian dialogbox. You can expand the directory tree to browse, locate,and select algorithms.

Open:

Lets you open the Module Control Panel (MCP) for thealgorithm you have selected in the algorithm library.(SeeWorking with an algorithm MCP on page 170 )

Find:

Opens the Find Algorithm dialog box. (See Finding analgorithm on page 166 )

Selected Algorithm:

Displays the name of the algorithm and an iconrepresenting the algorithm you have selected.

Algorithm licensingSome algorithms may not be available with the

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Geomatica license you have purchased. Files in theAlgorithm Library that have a lock icon to the left of thealgorithm name are not available. Contact PCI Geomaticsfor more information on your license package and foradvice on the best Geomatica license for your needs.

Algorithm categoriesAlgorithms are organized by themes or categories into adirectory tree containing two top-level categories. TheAlgorithm list can appear in two different ways. If createdfrom a user-defined category, the Algorithm Library listopens with the User Defined category expanded and atthe top of the directory tree. The PCI Predefined directoryis collapsed and at the bottom of the directory tree. If youhave not added a user-defined category, the AlgorithmLibrary list opens with the PCI Predefined directory. In thePCI User Defined category, algorithms are listed insub-category folders within a top-level folder.

Moving down the directory tree, the top-levelalgorithm categories are:

User Defined (top-level directory)

PCI Predefined (top-level directory)

• All Algorithms• All Bitmap Algorithms• All Image Algorithms• All Vector Algorithms• Geomatica• Analysis• Classification

• Data Interchange• Image Correction• Image Processing• Radar Analysis• Spatial Analysis• Utilities

Algorithm sub-categories

When you open the Algorithm Librarian dialog box, manyof the top-level category folders contain severalsub-category folders. The following lists show thesub-categories for each of the top-level folders.

All Algorithms:

Lists all the algorithms available in the Algorithm Library.

All Bitmap Algorithms:

Contains all the Geomatica algorithms that can be usedwith bitmap data.

All Image Algorithms:

Contains all of the Geomatica algorithms that can beused when working with Images.

All Vector Algorithms:

Contains all of the Geomatica algorithms that can beused with vector data.

Geomatica:

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Lists algorithms on the basis of your Geomatica license.This folder may contain a combination of sixsub-categories, depending on your license:

• Fundamentals• Prime• Optical• ATCOR3• Radar• Hyperspectral• Hyperspectral Image Compressor• Pan Sharpening

Analysis:

Contains the following Geomatica algorithms foranalyzing data:

• AVHRR• DEM Analysis• Favorability Analysis• Geological/Geophysical Analysis• Hydrological Analysis• Hyperspectral Analysis• Multi-layer Modeling• Vegetation Analysis

Classification:

Contains six sub-category folders:

• Advanced Classification• Data Exploration• Neural Networks• Post-Classification Analysis• Supervised Classification

• Unsupervised Classification

Data Interchange:

Contains six sub-categories of algorithms:

• CD Reading/Utilities• Image Interchange• Oracle Database Loading• Tape Reading• Tape Writing/Utilities• Text File Interchange• Vector Interchange

Image Correction:

Has four sub-directories:

• Atmospheric Correction• AVHRR Orbital Navigation• Geometric Correction• Image Mosaicking

Image Processing:

Has seven sub-directories:

• 3-D Rendering• Data Fusion• Enhancements• Frequency Transforms• Image Filtering• Image Operations• Image Transformations

Radar Analysis:

Contains four sub-directories:

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• Airborne Radar Analysis• Polarimetric SAR Analysis• SAR Speckle Filtering• SAR Radar Analysis

Spatial Analysis:

Has five sub-directories:

• Utilities• Proximity Analysis• Overlay Analysis• Topographer• Conversion Tools

Utilities:

Has four sub-directories of utility algorithms:

• Interpolation• PCIDSK Reports• PCIDSK Utilities• Vector Utilities

Finding an algorithmAll of the algorithms listed in the Algorithm Library showthe name of an algorithm followed by a brief descriptionof what it does.

There are several ways to find algorithms:

• Open on page 164 the Algorithm Library andbrowse for algorithms that work with basic datatypes. For example, the PCI Predefined foldercontains sub-folders for bitmap, image, and vectoralgorithms.

• Browse on page 164 through the categories byclicking the folders and sub-folders in the AlgorithmLibrary tree.

• Search on page 166 for an algorithm using the FindAlgorithm utility.

You can decide which method to use based on theinformation you have about the algorithm and what tasksyou want to perform on your data. (See Searching for analgorithm by category on page 167 .)

Using the Find Algorithm utility

If you know the name of an algorithm you want or you arenot sure, you can use the Find Algorithm utility to locate itquickly. You can search through the entire library usingkeywords to locate an algorithm, or you can searchthrough the contents of a selected folder.

1. In the Algorithm Librarian dialog box, right-click afile folder and click Find.

2. In the Find Algorithm dialog box, type all or part ofthe algorithm name in the Find what box.

3. Enable any of the following check boxes:• Match algorithm name # searches for an

algorithm using the name of the algorithm.• Match algorithm description using any

keyword # searches the Algorithm Librarybased on any of the keywords you haveentered in the Find what box.

• Match algorithm description using allkeywords # searches the Algorithm Librarybased on all of the keywords you have enteredin the Find what box.

• Wrap around searches through the Algorithm

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Library continuously until you decide to stop.4. Click Find Next.

The Algorithm Librarian automatically opens thefolder where your algorithm is located and thealgorithm is selected.

If you want to find another algorithm with a similarname, click Find Next again.

Note: To search the entire contents right-click the AllAlgorithms folder or right-click anywhere inside theAlgorithm Library other than on a file folder. You can alsouse the Find button to search the entire directory tree aswell as a selected category.

Searching for an algorithm by category

The Find Algorithm dialog box lets you search throughthe algorithm library using the name of an algorithm orusing keywords. You can also control the way the resultsof your search are displayed.

Find what: Lets you enter either an algorithm name or akeyword description.

Match algorithm name: Lets you search for an algorithmusing the name of the algorithm. For a list of Modeler andAlgorithm Library names and references see theGeomatica online Help.

Match Algorithm description using any keyword: Letsyou search the algorithm library based on any of thekeywords you have entered in the Find what box.

For example, with this option selected, a search on#Classify report# returns any algorithm with either of thewords classify or report in the algorithm description.

Match Algorithm description using all keywords: Letsyou search the algorithm library based on all of thekeywords you have entered in the Find what box.

For example, with this option selected, a search on'Lookup Table' returns only algorithms with both of thewords Lookup and Table in the same algorithmdescription.

Wrap around: The wrap around option lets you searchthrough the algorithm library continuously until you decideto stop. When this check box is enabled, the FindAlgorithm utility continues to show the results of thesearch each time you click Find Next. When this checkbox is disabled, the utility searches through the AlgorithmLibrary once. When the search is completed, the FindAlgorithm utility shows an End of search message.

1. Locate a category by scrolling down the AlgorithmLibrary list and select the file folder for the categoryyou want.

2. Click Find.3. In the Find Algorithm dialog box, enter a name or

keyword for the algorithm in the Find what box.4. Enable a check box for any search criteria you want

to use.5. Click Find Next.

Creating user-defined categories

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The Algorithm Library contains a top-level, user-definedfolder. You can create new folders in the User Definedfolder to hold collections of your favorite algorithms.When you drag an algorithm icon from a PCI-predefinedfolder to a User Defined folder, a shortcut to the algorithmis created.

A shortcut menu allows you to search user-definedfolders, open and close any open MCPs, create newcategories, show and hide folders, rename individualfolders, and access online Help.

The User Defined shortcut menu has the followingoptions

Find: Opens the Find Algorithm dialog box. (See Findingan algorithm on page 166 )

Close All Panels:

Closes all open MCPs in the PCI-predefined folders.

New Category:

Adds a new folder to the User Defined folder.

Hide:

Hides the User Define folder.

Show All:

Shows all of the folders in the User Defined directory,including any folders that have been hidden using the

Hide command.

Rename:

Lets you rename the User Defined directory.

Help:

Opens the Focus Help for the Algorithm Library.

1. From the Algorithm Librarian dialog box,right-click the User Defined folder and click NewCategory.

2. Type a name for the new category and press Enter.3. If you want to add a second folder level to your new

User Defined folder, right-click a new categoryfolder and repeat the procedure.

Adding algorithms to the user defined folder

You can create a collection of shortcuts to your favoritealgorithms by dragging the algorithms from aPCI-predefined folder to a User Defined folder. You canalso create a shortcut by right-clicking a PCI-predefinedalgorithm and clicking Add to User Defined.

1. Right-click the user-defined folder and clickRename.

2. Type a new name and press Enter.

Using an algorithm

Every algorithm in the Algorithm Library has a ModuleControl Panel (MCP) that you can open from the

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Algorithm Librarian dialog box. You use the MCP tocontrol data inputs and outputs and to assign the requiredinformation for the results you want.

• In the Algorithm Librarian dialog box, right-click analgorithm and click Open.

You can also double-click the algorithm.

About module control panels

Algorithm MCPs are tabbed dialog boxes. The number oftabs and the controls they contain vary depending on thedata requirements and the number and type ofparameters available to the algorithm.

Not all algorithm MCPs look the same. You canencounter some variation in the algorithm MCP inputs,functions, and features. In general, a MCP has one tabeach for file selection, input parameters, and log. TheFiles tab typically has a pane labelled Input Ports andmay have a pane labelled Output Ports. The InputParams tab items vary according to the requirements ofthe algorithm you are using. Some MCPs also have anOutput Parameters tab that contains controls for thealgorithm output.

Typically, an algorithm MCP has tabs and controls similarto those shown in the following example.

Files tab

Lets you direct the data that you want to process with the

algorithm you have selected. Most algorithm MCPs haveInput Ports panes and Output Ports panes under theFiles tabs and some MCP Files tabs have additionalcontrols.

Input Ports:

Allows you to select the data you want to process withthe algorithm you have selected. You can use dataalready open or you can use the Browse button to selectother input data.

Browse:

Opens a file selection dialog box, where you can browsefor input data. You can open data directly from anyAlgorithm MCP using the Browse button under the Filestab.

Output Ports:

Lets you direct the output to a viewer, to a project file, orto both. You can save the output to the location you arealready working in or you can use the Browse button tosave your output to another location.

Browse:

Opens a file selection dialog box, where you can saveyour algorithm output to another location.

Input Params tab:

Lets you set the parameters for the algorithm input data.

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Each algorithm has a unique set of parameters.

Output Parameters Tab:

Provides parameter controls for the output from youralgorithm. Not all MCPs have an Output Parameters tab.

Log tab:

Displays run-time progress, including any run-time errorsthat occur when you run the algorithm. When you runyour algorithm a progress monitor opens indicating theprogress of the algorithm. When the algorithm hasfinished running the algorithm MCP automaticallychanges to show the Log tab information.

Note: Some algorithms work only on a single layer, but inmost cases algorithms can use most or all of the files andlayers in a project.

Finding help topics for all algorithms

Online Help is available for all algorithms. You can findthe details of what the algorithm does and what the inputand output requirements are for each algorithm in theGeomatica Help.

1. From the Help menu, click General.2. In the Geomatica Help, click the Contents tab and

expand the Geomatica Algorithm Reference topic.3. Expand the Modeler and Algorithm Librarian

Reference topic.

All of the algorithms for Modeler and the AlgorithmLibrary are listed in alphabetical order.

Finding help from the Algorithm Librariandialog box

1. From the main menu, click Tools and selectAlgorithm Librarian.

The Algorithm Librarian dialog box appears.

2. Navigate to the algorithm.3. Right-click the algorithm and select Help.

Finding help from a Module Control Panel

You can find help from the Module Control Panel (MCP)of a selected algorithm.

1. From the main menu, click Tools and selectAlgorithm Librarian.

The Algorithm Librarian dialog box appears.

2. Navigate to the algorithm and select it.3. Click Open.

The MCP for the algorithm appears.

4. Click the Help button.

Working with an algorithm MCP

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Algorithm MCPs provide the controls for using thealgorithms in the Algorithm Library and are linked directlyto any open data. If you have data loaded in Focusbefore using the Algorithm Library, the data in the currentproject is listed under the Files tab in the Input Ports paneof the algorithm MCP. You can select the input layers youwant to process under the Files tab in the MCP InputPorts pane before you run the algorithm.

Working with an exampleIn the following example, the ASP algorithm is used tocalculate the surface aspect of elevation data. Thisalgorithm is found in the Spatial Analysis category underthe Topographer sub-category.

The ASP algorithm calculates the surface aspect ororientation angles from an elevation image. These anglesrepresent the directions the slopes are facing. The outputimage contains orientation angles from 0 to 360 degrees,relative to the top of the image, with areas of zero slopeassigned a single user-specified value.

The SLP program calculates the surface slope. Together,the ASP and SLP programs can completely define asurface in terms of degree of slope and direction it isfacing for every pixel in the image.

To begin this exercise, make sure you have imageryopen in the view pane and the Algorithm Library is open.Search for and open the ASP algorithm.

Using the ASP algorithmWhen the algorithm is opened from the Algorithm Library,configure it using the ASP MCP.

Setting up the input port

The input port contains the elevation layer and must be araster layer. This connection is mandatory.

1. In the ASP Module Control Panel, click the Filestab.

If necessary, expand all nodes next to InputElevation Layer to show all the available inputchannels.

2. Enable the check box next to channel 10 [16S]USGS Elevation Data.

Setting up output ports

The output port contains the aspect layer, which needs tobe a raster layer. This connection is optional.

1. Expand all nodes next to the Output Aspect Layerto show Viewer and Untitled.pix as the availableoutput options.

For the current example, direct your output to boththe viewer and to a .pix output file of your choice.

2. Enable the check box next to Viewer.3. If you want to select an output file as an output

port, enable the check box next to Untitled.pix.

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4. Select Untitled.pix.5. Click Untitled.pix again, type Calculate surface

Aspect.pix, and press Enter.

Setting up input parameters

The ASP algorithm is controlled by the input parameters.Calculation of the real and projected areas depends onthe proper specification of the following values:

Pixel X Size (m)

Specifies, in meters, the X dimension of each pixel on theground.

Pixel Y Size (m)

Specifies, in meters, the Y dimension of each pixel on theground.

Elevation Step Size (m)

Specifies, in meters, the elevation corresponding to eachgray level. A change in the size of the Elevation Stepresults in a corresponding change in the gray level in theelevation image. This parameter is mandatory.

Zero Slope Image Value

Specifies the value that will be assigned to pixels in theoutput image when the intermediate slope calculation iszero. If not specified, these pixels are assigned a value of510 because the output channel is 32-bit.

1. Click the Input Params 1 tab.2. To change the Pixel X Size in meters, modify the

value in the text field for the parameter asnecessary.

The default value is 30.0 meters.

3. To change the Elevation Step Size in meters,modify the value in the text field for the parameteras necessary.

The default value is 1.0 meter.

4. To change the Zero Slope Image Value, modify thevalue in the text field for the parameter asnecessary.

The default value is none.

Running the ASP algorithm

Once you have set up the algorithm, you can run it fromthe ASP MCP.

• In the ASP Module Control Panel, click Run.

Viewing the results

After running the ASP algorithm, you can viewinformation about the output layer.

To view output layer information

1. Click the Maps tab in the viewer.

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To view output file information

1. Click the Files tab.2. Expand the Files node.

You should see the following information listedunder Rasters:

1[32R]ASP Aspect from elevation channel 10.

To view execution status

1. Click the Log tab.

If the algorithm ran successfully, the messagesTime of execution and Execution Successful aredisplayed in the text area under the Log tab.

To view the program results

1. Study the surface aspect of the elevation data in theviewer.

If the algorithm ran successfully, the messagesTime of execution and Execution Successful aredisplayed in the text area under the Log tab.

Understanding the resultsThe ASP algorithm uses the elevation layer in the inputchannel to calculate the corresponding aspect angles.

The results are written to the aspect layer in the outputchannel, which is either the viewer or a .pix file. Thecorrect calculation of the aspect values depends on theproper specification of the Pixel X Size and Pixel Y Size.

Aspect Values:

Aspect at a point is calculated as the orientation of theplane formed by the vector connecting the left and rightneighbours and the vector connecting the upper andlower neighbours of the pixel or the angle between thetop of the image and the projection of the normal vectorof this plane onto the horizontal plane. True aspectvalues will always range between 0 and 360 degrees.

Zero Slope Values:

Areas where the slope is zero are treated as a specialcase and are assigned a user-specified aspect valuefrom the Zero Slope Image Value input parameter. If thisinput parameter is not specified, a default value of 510 isassigned.

Adding functions to the algorithmlibraryYou can create new algorithms using PACE and EASIprogramming and add them to the Algorithm Library,which uses definition files to describe available modulesand their properties. Module definition files define thealgorithms in the Algorithm Library.

You can find module definition files in the etc folder,

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located in the Geomatica program folders on your harddisk. Module definition files use the file name extension.def. New modules must be added to a specific packagedefinition file in order to be accessible in the AlgorithmLibrary.

You can convert your PACE programs into Modelermodules or Focus algorithms without having to writescripts using the Geomatica Software Development Kit(SDK). The Geomatica SDK lets you create your ownalgorithms and add them to the Algorithm Library.Information for EASI and PACE programming languagesis available in the Geomatica SDK. (See the PCIGeomatica SDK).

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Chapter 5Starting a classification session

To start a supervised classification session

1. From the Map tab, right-click the layer you want toclassify and click Image Classification and thenclick Supervised.

To start an unsupervised classification session

1. From the Map tab, right-click the layer you want toclassify and click Image Classification and thenclick Unsupervised.

To start a classification session

1. In the Session Selection dialog box, click NewSession if you want to begin a new classification.

2. If you want to choose a previous selection, click asession in the Sessions available box and click OKor click File to select a file.

Unsupervised classification

An unsupervised classification organizes imageinformation into discrete classes of spectrally similar pixelvalues. To perform unsupervised classification in Focus,you work through panels and dialog boxes to configureyour data files and to choose the number of classes thatthe computer differentiates.

When you finish configuring a classification, you can runthe process. Focus automatically classifies the spectralvalues in the image data. You can view the classificationresults in the view pane and as a classification report.

Configuring a new classification session

You can initialize a new classification session with orwithout data files open.

1. In the Session Configuration dialog box, type aname in the Description box.

It is not necessary to identify features in the imagein unsupervised classifications. Unsupervisedclassifiers do not use training sites; they divide theimage pixels into natural groupings of statisticallysimilar gray-level pixel values.

If you want to work with more than one algorithm inthe same session, use the Open command on theSelect Algorithm dialog box. The Select Algorithmdialog box remains open until you click Close.

2. Adjust the Red, Green, and Blue color values to thecombination you want by clicking the appropriatecolumn for each channel.

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A project can contain several classifications, eachone using different sets of input channels.

3. In the Input Channels column, select channels youneed for your project.

4. Select an output channel to store your classificationby clicking in the Output Channel column for thechannel you want to use.

You can select an empty channel or you can overwrite an existing channel, such as a channelcontaining imagery of no consequence.

If there are no desirable or available outputchannels, click Add Layer and enter values forchannels in the Channels to add boxes for theappropriate channel types. Click Add.

5. Click OK.

The Unsupervised Classification dialog boxopens. Focus adds a classification metalayer to theMaps tree and the RGB reference image youspecified opens in the view pane.

Initializing unsupervised classification

The Unsupervised Classification dialog box allows you tochoose the type of algorithm and the parameters youwant to use in the classification.

1. In the Unsupervised Classification dialog box,enable one of the following algorithm options:

• K-Means• Fuzzy K-Means• IsoData

2. In the algorithm Parameters table, click in theappropriate box in the Values column and enter thecriteria that you want in the classification.

3. In the Classifications Options area, enable any ofthe following check boxes:

• Show report• Save signatures• Create PCT

4. Choose a training site option from the Use bitmapas mask list box.

If you choose an option other than None, choose amask region from the Classify region list box.

5. Click OK.

Note: It is recommended that you use many clusters (forexample, the full 255 allowed in an 8U channel) and thenperform aggregation to get the actual number ofinformation classes you want.

Note: To view the unclassified image, drag theunclassified image file layer to the top of the Maps treeabove the Classification MetaLayer. The original imageappears in the view pane.

Reading a classification report

The classification report indicates the distribution of pixelvalues across the number of classes set in theUnsupervised Classification dialog box, a date stamp,and the file path for the classified imagery. Theclassification algorithm is also listed with the inputchannels and the channel in the data file where theresults are stored.

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The report also lists the number of clusters created by theclassification with the details for each cluster.

Clusters are groups of pixels with similar spectralproperties. The report tells you how many pixels make upeach cluster, the mean brightness value, and thestandard deviation for each of the input image channels.

Supervised classificationIn supervised classification, you must rely on your ownpattern recognition skills and knowledge of the data indetermining the statistical criteria (signatures) for dataclassification. To select reliable training sites, you shouldhave some information, either spatial or spectral, aboutthe pixels that you want to classify.

The location of a specific characteristic, such as a landcover type, may be known through reports on groundtruth. Ground truthing refers to the acquisition ofknowledge about the study area from field-work analysis,aerial photography, or personal experience. Ground truthdata is considered to be the most accurate (true) dataavailable about the area you want to study and should becollected at the same time as the remotely-sensed data,so that the data corresponds as much as possible.

Sometimes, ground truth data may not be accurate, dueto errors, inaccuracies, and human error. Globalpositioning system (GPS) receivers are useful inconducting better ground truth studies and collectingtraining sites.

The supervised classification process

Carrying out effective supervised classification may takepractice. It requires you to develop the ability to recognizeyour target features and visual patterns in your imagedata. The process can be repetitive, depending on howquickly you can produce satisfactory results.

The diagram below shows the task flow of the SupervisedClassification process.

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The Supervised Classification Process

Initializing a supervised classification

Like unsupervised classification, supervised classificationis initialized as a session. The initialization procedurealso helps you manage subsequent classifications on the

same files without re-initializing a new session each time.

Focus automatically assigns red, green, and blue (RGB)values to the first three channels. You can select theexact combination of channels by assigning the colorchannels that define the reference image for collectingyour training sites and for doing any post-classificationanalysis.

1. From the Analysis menu, click ImageClassification and then click Supervised.

2. In the File Selector dialog box, locate and select animage file you want to classify.

3. Click Open.4. In the Session Selection dialog box, click New

Session.5. In the Session Configuration dialog box, type a

name for your classification in the Description box.

Note: When naming classification sessions, enter aname in the Description text field that will distinguishyour current classification from others you create.

Specifying the reference image

Focus automatically assigns red, green, and blue (RGB)values to the first three channels. You can assign colorchannels to define the reference image that will be usedduring training site data collection and in any subsequentpost-classification analysis.

Because supervised classification requires you to rely onyour own pattern-recognition skills and a prior knowledgeof the scene, you may need to visually identify your

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training areas from familiar colors in the ground cover. Insuch cases, you must change the RGB values to matchthe TM bands in the image data to produce a truecolor-reference image.

The task of collecting training areas is made easier byworking with a reference image that simulates normal ortrue color. However, personal preferences often guide thechoice of band - color combinations for interpretivepurposes. In some applications, you must use a differentcombination of color channels; for example, channels thatfall outside the visible color range.

Whatever your preference, it is unlikely that the defaultcolor assignment offered in the Session Configurationdialog box will coincide with your choice. You can resetthe color assignments by clicking the corresponding cellof the desired channel in each of the Red, Green, andBlue columns. You can rearrange the color channels tosee a true color rendition of the image in the view pane.

Specifying the input channels

Spectral classes are groups of pixels that have uniform ornearly similar brightness values in the different spectralchannels of the data. The spectral attributes of theclasses used to train the computer are determined by thespectral channels that you choose to include in thetraining and classification process. You can use Focus tomatch the information classes you create with a spectralclass in the image data.

Note: To determine the optimal combination of bands for

spectral discrimination in your training sites you can usethe channel select (CHNSEL) algorithm in the AlgorithmLibrarian.

Once you have set the RGB values for true color, youcan define the spectral attributes for the ground coveryou want to classify. You must choose a set of datachannels that will define the spectral attributes orsignatures in your classes.

To select the input data set

1. In the Session Configuration dialog box, click in acell next to a spectral channel in the InputChannels column.

A check mark indicates that the channel is selected.

2. Select a channel for collecting your training sites.

Note: You can use an empty channel, a channelwhere the contents can be over written or you canadd a new working channel.

You can add empty channels to the SessionConfiguration list and the Files tree.

To add a new channel

1. Click the Files tab and right-click the image filefolder.

2. Click New and then click Raster Layer.3. In the Add Image Channels dialog box, choose the

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bit depth and number of new channels you want toadd.

4. Click Add.

If you want to close the Add Image Channelsdialog box, click Close.

Once you have added channels, you must selectthem in the Session Configuration dialog box so thatthey receive the classification output. If you havenot added empty channels, you must selectchannels that you intend to overwrite.

To select the output channel

1. In the Output Channel column, click a channel.2. Click OK.

The details of the configuration setup are nowshown in the Maps tree and the reference imageopens in the view pane. The Training Site Editordialog box opens with a blank training channel.

The training channel is now write-enabled andready for you to begin collecting your training sites.

Training sites and ground cover

You designate training sites based on samples ofdifferent surface cover types in your imagery by drawing

colored regions or areas over the parts of the image thatare likely to be the information classes you want toextract.

You cannot know for certain what the actual ground coverin an image is by referencing only the image; therefore,samples (training sites) must be based on familiarity withthe geographical region and knowledge of the actualsurface cover types shown in the image.

Training sites are areas in an image that arerepresentative of each of the land cover classes that youwant to define. Focus examines the pixel values withinthe training sites in order to compile a statistical signaturefor each training site class. The training signatures serveas the interpretation key for each pixel in the image. Allpixels in the image are compared to the signatures andthen classified.

You can use the Training Site Editor to create trainingsites to supervise the classification.

1. From the Training Site Editor, click Class and thenclick New.

2. Double-click Class-01 in the Name column andtype a name for the training site.

3. Click one of the following:

Drawing a class training site

Once you have created a class with the Training SiteEditor, you can draw training sites over the referenceimage in the view pane.

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1. In the Maps tree, select the Training areas layer inthe Classification MetaLayer.

2. On the Editing toolbar, click the New Shapes arrowand choose Polygon.

3. Click the reference image within the bounds of thesubject area where you want to start the trainingarea outline.

4. Trace the outline of the polygon by clicking at theend of each line segment.

5. To complete the polygon, double-click near the firstpoint in the training site.

6. Identify similar areas from the imagery that matchyour first polygon.

The more areas you identify as training sites, thehigher the accuracy of the classification.

Note: Overlapping your training area boundariesreduces the reliability of your training sites.

Making corrections

1. On the Editing toolbar, click the Raster Erasearrow and choose an erase option.

2. Trace over the training site you want to remove fromthe image.

3. Double-click to erase. (See About the EraseSettings dialog box on page 181 )

About the Erase Settings dialog box

The Erase Settings dialog box lets you choose a fill

polygon option and adjust the line width of the RasterErase tool.

Fill Polygon:

Removes the inside of a polygon when using the ErasePolygon option.

Line Width:

Lets you enter a line width, in pixels, for the Raster Erasetool.

Changing training site colors

You can change the color of your training sites. Focusautomatically assigns colors to new training sites. Yourfirst class may be green and your second class may beblue when they are drawn in the view pane. You canchange the color of the class sites to any color.

1. In the Maps tree, right-click the ClassificationMetaLayer and click Open training sites.

2. In the Training Site Editor, click a color.3. In the color dialog box, make any changes to the

color.4. Choose a color model from the Model list box and

make any changes to the color channels in theappropriate spin boxes.

5. Click OK.

Importing training sites

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You can also import vectors, bitmaps, or signatures anduse them as training sites. The Import Vectors dialog boxuses rasterized vector polygons to define training sites.

1. In the Training Site Editor, right-click a class row.2. Click Import and then clickVector(s).

Importing vectors

The Import Vectors dialog box lets you

• Import vector segments• Choose which vector layer is to be rasterized• Choose how a vector layer is rasterized

Vectors Table

The import table lists all the vector segments that arepresent in the selected file. There are five columns:

• Segment: Lists the number associated with eachvector segment in the selected database.

• Interior Points: Identifies which vector segmentscontain the point information that will be used todefine the rasterized value of the polygons. You canselect more than one interior point segment.

• Polygon Boundary: Indicates which vectorsegments contain the polygon information that willdefine the boundaries of the rasterized polygons.You should select one or more of these segments.

• Field: For each selected vector segment, thischoice determines which field value is used to gridthe polygons. Numeric attributes are displayed.Some vector segments may contain differentattributes.

• Description: Displays the descriptions associatedwith each vector segment.

Supported Vector Formats

When importing vectors into a training site editingsession, the following vector types are supported:

• ALL_POLYGONS• GDBLTopoAreas

This information can be found in the MetaData tab for thevector layer properties.

1. In the Import Vectors dialog, choose the filecontaining the vectors you want to import from theFile list box.

2. If the file you want is not listed, click Browse, locateand select the file you want in the File Selectordialog box, and click Open.

3. Click in the Interior Points column next to therasterized value you want to define.

A check mark indicates the segment has beenselected and will override any entry in the Fieldcolumn.

4. Click in the Polygon Boundary column next to therasterized value you want to define.

A check mark indicates the segment has beenselected.

5. Click in the Field column for a segment and choosea rasterization value to change the field used forrasterization.

This column is ignored if the Interior Points columnhas been enabled.

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6. Click Rasterize.

Importing a vector does not overwrite existingclasses. The polygons are added to the imagewhere no classes exist. This occurs for pixels with avalue of zero.

Opening the Import Bitmaps dialogbox

The Import Bitmaps dialog box uses existing bitmaps todefine training sites.

• In the Training Site Editor, right-click in a row andclick Import and then click Bitmap(s).

About the Import Bitmaps dialog box

The Import Bitmaps dialog box lets you:• Create a new class with the specified bitmap as its

training site• Change a class training site that you choose in the

Training Site Editor• Replace the class training site selected in the

Training Site Editor

By default, imported bitmaps do not overwrite existingtraining sites. To overwrite training sites, enable theOverwrite existing training areas check box.

Importing a specified bitmap as its trainingsite

1. Enable one of the following options:• New class: creates a new class with the

specified bitmap as its training site• Current: augments the training site of an

existing class2. Select a bitmap from the Bitmaps available list.

If you want to overwrite training sites, enable theOverwrite existing training areas check box.

3. Click OK.

Importing signatures from the trainingsite editor

The Import Signature dialog box displays a list of thesignatures that are compatible with the currently selectedclass. Compatibility is determined by the combination ofinput channels used to generate the signature.Compatible signatures must have the exact same set ofinput channels as those being used for the currentclassification.

Instead of calculating a signature segment from trainingsites, you can import an existing signature from theImport Signature dialog box.

1. In the Training Site Editor table, right-click a classrow and click Import and then click Signature.

2. In the Import Signature dialog box, select the

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signature you want to import.3. Click OK.

Filling polygons using the RasterSeeding functionWhen your training sites need to be irregular shapes orpolygons made of homogeneous pixel groups, you canuse the Raster Seeding function to grow and fill a regionof similar pixels.

You can vary the tolerance of the growth in the RasterSeeding dialog box to slowly adjust the size of the grownregion. Higher tolerance settings create large growthregions and lower tolerance settings create smallergrowth regions. You can use the Raster Seeding functionto grow regions of various sizes.

The Raster Seeding dialog box opens from the NewShapes list on the Editing toolbar. (See About the RasterSeeding dialog box on page 184 )

About the Raster Seeding dialog boxThe Raster Seeding dialog box allows you to select aninput file and layer, view the name and location of theinput files, and set the properties of the raster seedingoutput.

Input Layer

The Input Layer area lets you read the location of theinput data and choose the layer on which to perform theseeding operation.

Selection Criteria (Layer):

Provides a list of files and lets you choose the input datafor a seeding operation.

Layers:

Opens the Select Seeding Layers dialog box. (See Fillinga polygon on page 185 )

Selection Layers:

Reports the name and location of your input data files.

Output Layer

The Output Layer area shows the name and location ofthe output files.

Selected Layer:

Reports the name and location of the selected layers.

Properties

The Properties area lets you set the Input Pixel Valuetolerances and choose from either a four-connect or aneight-connect option.

Input Pixel Value Tolerance:

Lets you enter a pixel value as a seeding tolerance andchoose an X value from a list.

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Neighborhood:

Lets you choose either a four-connect or aneight-connect option to set the kernel size for the rasterseeding operation.

Filling a polygon

The Select Seeding Layers dialog box lists all of theavailable input layers and allows you to select the layersyou want to include in the seeding operation.

Clear:

Clears all selected layers from the list.

Select All:

Lets you select all of the listed layers.

Selected Layers:

Reports the layers you have selected.

1. In the view pane, click a polygon.2. On the Editing toolbar, click the New Shapes arrow

and choose Raster Seeding.3. In the Raster Seeding dialog box, select the layers

with which you want to fill the polygon.4. Click OK.

Merging classes

The Merge command combines several classes into one.Merge affects the portion that is opened and the entiretraining channel.

1. From the Training Site Editor, click Class and thenclick Merge.

2. In the Merge Classes dialog box, select the classesyou want to merge from the Source list.

If you want to select multiple classes, hold down theCtrl or Shift key and click the classes you want tomerge.

3. Select a destination class in the Destination list.4. Click Merge.

Analyzing training sites

Often during classification, unique spectral classesappear that do not correspond to any of the classes youwant to use. In other cases, a broad information classmay contain a number of spectral sub-classes withunique variations. This can be caused by a mixture ofground cover types appearing in the image at the time itwas recorded, or by shadows and variations in sceneillumination.

Focus offers several methods for insuring that yourtraining sites are both representative and complete.Youcan work with training site data using the Training SiteEditor, the Signature Statistics dialog box, and theScatter Plot dialog box.

You can view and test the reliability of your training sites

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by creating a histogram in the Class Histogram Displaydialog box. The histogram shows the frequency oftraining site pixels as a percentage of the number ofpixels in your training sites. A histogram should have auni-modal shape displaying a single peak. A multi-modalhistogram indicates the likelihood that the training sitesfor that class are not pure, but contain more than onedistinct land-cover class.

• From the Training Site Editor, right-click in a classand click Histogram.

In the Class Histogram Display dialog box, theX-axis in the histogram represents the gray-levelvalue for the image channel with a range of 0 to255. The Y-axis shows the frequency count as apercentage of the total count of pixels in the trainingarea corresponding to the gray value.

Testing signature separability

Signature separability is calculated as the statisticaldifference between pairs of spectral signatures. You canuse the Signature Separability dialog box to monitor thequality of your training sites. Divergence is shown as bothBhattacharrya Distance and Transformed Divergence,with the Bhattacharrya Distance as the defaultcalculation.

Both Bhattacharrya Distance and TransformedDivergence are shown as real values between zero andtwo. A zero indicates complete overlap between the

signatures of two classes; two indicates a completeseparation between the two classes. Thesemeasurements are monotonically related to classificationaccuracies.

Note: Higher separability values indicate a goodclassification result

• From the Training Site Editor, click Tools and thenclick Signature Separability.

Testing separability with a scatter plotYou can use the Scatter Plot dialog box to show ellipticalgraphs for all training sites. A class ellipse shows themaximum likelihood equiprobability contour defined bythe class threshold value entered for the mean.

Threshold

is a relative measure used to control the radius of thehyperellipse for each class. By changing the thresholdvalues, you can reduce the chances of pixels beingclassified into more than one class.

Bias

is a value from 0 to one, where higher values weigh oneclass in favour of another. It can also be used to resolveoverlap between classes. You can use both of thesemeasurements to test the training site separability.

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Creating a scatter plot

You can use the Plot Ellipses options in the Class ListTable to assess the separability of your spectral classesand to refine and edit your training sites.

A scatter plot should display an ellipse for each of thetraining classes. When there is overlap in several of theband combinations, you must adjust the threshold values.

1. From the Training Site Editor, click Tools and thenclick Scatter Plot.

2. In the Scatter Plot dialog box, click in the PlotEllipses column for each class that you want toinclude in the scatter plot.

A check mark indicates a class has been selected.

If you want to magnify a section of the graph,right-click on the area in the graph and click ZoomIn.

Adjusting scatter plot threshold values

1. From the Training Site Editor, double-click theThreshold column for the class you want to adjustand type a new value.

The class ellipse adjusts automatically to show thechange in the threshold value.

2. From the Tools menu, click Classification Previewand click one of the following:

• Maximum Likelihood

• Maximum Likelihood with NULL class• Parallelepiped• Parallelepiped with MLC Tiebreaker• Maximum Distance• Show Training Sites

3. Click Save&Close.

Altering the view range for the X andY axes

You can use the Graph Controls option in the Scatter Plotdialog box to alter the view range for the X and Y axes.

1. In the Scatter Plot dialog box, click GraphControls.

2. Enter values in the Min and Max boxes in the XView Range and Y View Range areas.

3. Click Close.

Exporting the scatter plot file

1. In the Scatter Plot dialog box, click GraphControls.

2. Click File in the Export area.3. Locate and select a file in the File Selector dialog

box.

The default file format is PCIDSK. TIFF, BMP, andPostScript formats are also available.

4. Click Save.5. Click Export in the Graph Controls dialog box.

Displaying the color scale legend

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You can display the color scale legend on the side of thescatter plot in the Scatter Plot dialog box.

1. In the Scatter Plot dialog box, click GraphControls.

2. Enable the Show legend check box.

Printing the scatter plot

You can print the displayed histogram or its zoomedversion.

1. In the Scatter Plot dialog box, click GraphControls.

2. In the Options section, enable the Fix aspect ratiocheck box, if required.

3. In the Background list box, select a backgroundcolor for the scatter plot. The selected color appearsbehind the scatter plot in the Scatter Plot dialog box.

4. Click Print and specify printer settings.5. Click Print.

Previewing the classificationYou can preview a classification result using one of thepreviewcommands in the Training Site Editor or from theUtilities option from the classification metalayer in theMaps tree.

The preview commands show how the input channels willbe classified using the training sites and class

parameters contained in the training channel.

You can preview with the following commands:

• Maximum Likelihood• Maximum Likelihood with NULL class• Parallelepiped• Parallelepiped with MLC Tiebreaker.• Minimum Distance• Show Training Sites

Setting the Maximum Likelihoodclassification preview

Ensure that you have selected a session that has beenconfigured.

1. In the control pane, click the Maps tab.2. Right-click the Classification MetaLayer and click

Open training sites.3. In the Training Site Editor, click Tools and then click

Classification Preview and then click MaximumLikelihood.

Removing the preview classification fromthe metalayer

1. In the control pane, click the Maps tab.2. Right-click the Classification Metalayer and click

Open training sites.

Creating a separability report

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You can create reports for a signature separability andsave them to data files.

1. Click Save Report.2. In the Save Separability Report dialog box, enter a

file name for the separability report in the File box.3. Click Save.

Saving the separability report to an existingfile

1. Click Save Report.2. In the Save Separability Report dialog box, click

Browse.3. In the File Selector dialog box, locate and select

the file.4. Click Open.5. In the Save Separability Report dialog box, click

Save.

Running a supervised classification

When you have analysed your training sites and testedtheir separability, you are ready to run a supervisedclassification.

1. In the Maps tree, right-click ClassificationMetaLayer and click Run Classification.

2. In the Supervised Classification dialog box, enableone of the following options in the Algorithm area

• Parallelepiped: forces every pixel in theimage to belong to one of the user-definedclass types. If you choose this option and wantto include Maximum Likelihood as a tie

breaker, enable the With MaximumLikelihood as tie breaker check box.

• Minimum Distance: forces every pixel in theimage to belong to one of the user-definedclass types.

• Maximum Likelihood: allows a null-classparameter option. In some cases, you want toextract classes, but there are many more landcover classes represented in the imagery.Therefore, you want a proportion of pixels leftunclassified, or null.

3. In the Classification Options area, enable any ofthe following check boxes:

• Show Report: generates a report of theclassification data.

• Save signatures• Create PCT: compares your classification with

another classification.4. Click OK.

The report should show a high overall training siteaccuracy. The information from each pixel in the trainingareas is compared to the information determined by theclassifier algorithm. The overall accuracy represents thepercentage of training-area pixels that were correctlyclassified. Your training areas are ideal examples of theclasses.

Testing accuracy with signature statistics

Focus lets you test the accuracy of a training sitecollection.The Signature Statistics dialog box displays thenumber of samples in the training area, indicatingwhether you have collected enough pixels to accurately

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represent the land cover. You can compare the statisticsfor several classes at the same time.

1. From the Training Site Editor, right-click a class andclick Statistics.

2. In the Signature Statistics dialog box, click a classin the table to display its statistics.

Note: Similarities cause errors during classification.Consider removing a channel from the list of inputs if youare not getting good results.

Viewing signature statistics

The Signature Statistics dialog box displays a table ofthe classes included in the currently selected image. Foreach class, the following columns are included:

• ID• Value• Name• Color• Threshold• Bias• Imported signature status• Description

General Report

The General report lists the mean and standard deviationfor each input channel under the class's training areamask.

• Click the General tab.

Viewing a matrix report

The Matrices report lists the following matrices for theclass signature:

• Class Correlation matrix• Class Co-variance matrix• Inverse Co-variance matrix• Triangular Inverse Co-variance matrix• Click the Matrices tab.

Comparing signature statistics

You can open a multiple Signature Statistics dialog boxesto view and compare the statistics of several differentsignatures at the same time.

• From the Signature Statistics dialog box, clickNew Panel.

Editing Class Signatures

You can also edit any of the cells in the class table.

Saving the signature statistics report

You can save both the general and matrices statistics forall of the classes to a text file.

1. In the Signature Statistics dialog box, click SaveReport.

The Save Statistics Report dialog box appears.

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2. Specify a file name and its directory path.3. Click OK.

Post-classification editingIn most cases, a classifier algorithm does not produceideal results. There are often occurrences of single-pixelmisclassification. A field may contain a few pixels ofanother class or there may be image data that fallsoutside training sites that affects the classification results.Class editing corrects errors by combining severalclasses.

Improving classification results

To improve a classification, first assess the accuracy ofyour results. The accuracy of a classification is measuredagainst a standard that is assumed to be correct. Theclassification accuracy increases as it approaches thestandard.

Once you have assessed the classification accuracy, youcan combine classes through a process known asaggregation. Combining classes creates a new aggregateclass. A maximum of 255 classes can be reassigned in asingle session. Aggregation is often performed on theresults of an unsupervised classification. A commonapproach in unsupervised classification is to generate asmany cluster classes as possible. With the benefit ofreference data or first-hand knowledge of a scene, youcan aggregate the spectral clusters into meaningfulthematic classes.

Initialize post-classification editing

You can combine several classes once you have editedyour classification. Like the aggregation process, classediting combines several classes; however, instead ofcombining classes throughout an image, you cancombine the classes for all pixels under a bitmap mask.

1. In the Maps tree, right-click ClassificationMetaLayer and click Post-classification Analysisand then click Class Editing.

2. In the Class Editing dialog box, click Image andthen click Select Classified Image.

3. In the Select Classified Image dialog box, choosethe output channel you selected when you initializedthe classification from the Channels available list.

4. Click OK.5. In the Class Editing dialog box, click Image and

then click Select Reference Image.6. In the Load Reference Image list, locate and select

the Red, Green, and Blue channels.

You must use the same reference image to performclass editing.

As you select a channel, its number is added to theR, G, and B boxes.

7. Click OK.

Once you have selected a reference image you canprepare to draw your bitmap mask.

Setting up a bitmap mask

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1. In the Class Editing dialog box, click Mask andthen click Create Mask from new Bitmap.

2. Ensure the Mask visible check box is enabled.3. In the Visible Image area, enable the Classified

option.4. In the Maps tree, click the bitmap layer.5. On the Zoom toolbar, click the Zoom to 1:1 Image

Resolution button.

Note: Images must be displayed at 1:1 or higher to drawa bitmap mask over the view pane. The drawing tools arenot available when images are zoomed to overview size.

Opening a bitmap mask

The Load Mask from Bitmap command produces a maskwith a bitmap that had been previously created. This isuseful if you want to replace the class of a particulartraining site with a new bitmap mask.

1. From the Class Editing dialog box, click Mask andthen click Load Mask from Bitmap.

2. In the Load Mask from Bitmap dialog box, select abitmap segment in the Bitmap segments availablelist.

3. Click OK.

Saving a bitmap mask

You can save the active mask as a bitmap.

1. From the Class Editing dialog box, click Mask andthen click Save Mask to Bitmap.

2. In the Save Mask to Bitmap dialog box, select abitmap segment in the Bitmap segments availablelist.

3. Click OK.

Masking an image area

The masked area combines classes. You can select aregion over the entire file to combine all of the classes inthe image.

Masking an image area is similar to creating a trainingsite. You can mask over a part of the image.

1. In the Maps tree, select the new bitmap layer belowthe Classification MetaLayer.

2. On the Editing toolbar, click the New Shapes arrowand choose Polygon.

3. In the view pane, draw a mask over the part of theimage you want to edit.

4. In the Class Editing dialog box, select a class inthe Source Classes area.

If you want to select all classes, click Select All.

5. Click the Merge Classes.6. In the View Controls area of the Class Editing

dialog box, disable the Mask visible check box.

If you want to use more than one mask to cover allof the image areas you want to edit, repeat theprocedure.

Opening an aggregation session

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Aggregation is the process of combining classes in orderto create a new aggregate class. A maximum of 255classes can be reassigned in a single session.Aggregation is often performed on the results of anunsupervised classification. A common approach inunsupervised classification is to generate as manycluster classes as possible. With the benefit of referencedata or first-hand knowledge of the scene, the analystaggregates the spectral clusters into meaningful thematicclasses.

1. From the Analysis menu, click ImageClassification and then click Post ClassificationAnalysis and then click Aggregation.

2. In the File Selector dialog box, locate and select afile.

3. Click Open.

Opening the Aggregate dialog box in anunsupervised session

• In the Maps tree, right-click ClassificationMetaLayer and click Post-classification Analysisand then click Aggregation.

Setting up an aggregation

Channel Setup

Before you can perform an aggregation, you must specifythe database channels that serve as the input and output

channels. This is done using the Channel Setup dialogbox.

Input Channel

This is the channel you want to aggregate and is typicallythe result of an unsupervised classification.

Output Channel

This is an empty channel. You store the results of theaggregation in this channel.

1. In the Channel Setup dialog box, select anunsupervised classification channel from theChannels available list.

2. Select an empty channel or an unfinishedaggregation result from the Output list.

3. Click OK.

Setting up a new aggregate class

Image classifiers do not always provide the desired levelof accuracy. As a result, a clean-up is often necessaryafter a classification. Aggregation is one of the fourpost-classification clean-up methods.

There are three main areas in the Aggregate dialog box.

View Controls

Use this area of the dialog box to choose different waysto view the classes and aggregates.

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Normal mode

Displays the aggregate classes along with the original, asyet unassigned, classes.

Input classes

Displays all the original input classes.

Current classes

Displays the classes that are currently selected in theInput Classes list.

Unassigned classes

Displays only the unassigned classes. Input classes thathave been assigned to an aggregate will be blacked out.

Aggregate classes

Displays all the current aggregates.

Current aggregate classes

Displays the aggregates that are currently selected in theAggregate Classes list.

Highlight color

Lets you choose a color for the class.

Input Classes

This table lists all of the classes in the selected inputchannel. Use this table to locate and select the set ofclasses to include in each of the aggregate classes. Youcan select multiple classes by holding down Shift or Ctrlwhile clicking a selection.

There are several tools available to assist you in theselection process:

Select Class at Cursor

Locates the class at the current cursor location within theview pane.

Highlight Classes

Displays the selected input classes in the chosenhighlight color, as selected in the View Controls area.

PCT

Changes the current pseudo-color table.

Aggregate Classes

This table contains a list of all the aggregate classes. Inaddition, there are four tools available to assist you:

New

Creates a new aggregate class.

Delete

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Removes an aggregate class from the list.

Class Initialization

Save

Saves all the details of the aggregation session to a textfile.

The following example of a text file that describes threeaggregate classes:

1 | Water |0 |0 |255| Water class | 10,20

2 | Crop |0 |255 |0 | Crops |

3 | Other Class |255|0 |0 | Water class | 40

To help you to identify and locate classes, use theHighlight color feature. The selected class(es) assumethe highlight color. Use the Highlight color palette tochange the color used for highlighting.

1. In the Aggregate Classes area, click New.2. Double-click the Name column for the new class

and type a name.3. Click the Color column for the new class and

choose a color.

The Add and Remove tasks are only active afterselections are made in both lists.

Creating an aggregate from a set of inputclasses

1. Select a row containing the class you want to addfrom the Input Classes area.

If you want to select multiple rows, hold down theCtrl or Shift key while selecting rows.

2. Select the row containing the aggregate class that isto receive the input class.

3. Click Add.4. Repeat steps 1 to 3 until the input classes are

assigned to the appropriate aggregate classes.5. Click Apply to Output Channel.

Changing the input and output channelassignments

1. From the Aggregate dialog box, click Setup.2. In the Channel Setup dialog box, select a new

input channel from the Channels available list.3. Select an empty channel from the Output list.4. Click OK.

Assigning a new PCT to the current session

Use the Generate or Import PCT dialog box to changethe pseudo-color table assigned to the current aggregatesession. You assign a new PCT in two ways:

• Generate PCT: Creates a PCT that attempts tosimulate a reference RGB image. Duplicating thelook of an RGB image may assist you in identifyingand locating areas within the image to beaggregated.

• Import PCT: Imports an existing PCT.

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Generating a PCT

1. From the Aggregate dialog box, click PCT in theInput Classes area.

2. In the PCT dialog box, click the Generate PCT tab.3. For each of the red, green, or blue channel

designations, select a channel from the Channelsavailable list.

4. Click OK.

Importing a PCT

1. From the Aggregate dialog box, click PCT in theInput Classes area.

2. In the PCT dialog box, click the Import PCT tab.3. Click File.4. In the File Selector dialog box, locate and select

the file containing the PCT segment you want toimport, and click Open.

5. Click Open.6. n the PCT dialog box, select a segment in the list.7. Click OK.

Saving the aggregate session

Aggregation is usually a lengthy process, especially if youwant to test and compare several different aggregationscenarios. It is recommended that you use the SaveAggregate Session feature periodically to save your work.

You must save the details of your aggregate session inorder to:

• Save intermediate results.• Generate different aggregation scenarios.

1. From the Aggregate dialog box, click Save.2. In the Save Aggregate Session dialog box, click

File.3. In the File Selector dialog box, select a destination

folder.4. Type a file name in the File name list box.5. Choose a file extension from the Files of type list

box.6. Click Open.7. Click Accept.

Aggregate sessions are saved as .txt files by default. Thefollowing example shows a typical line in a savedaggregate text file.

1 | Rural | 0 | 204 | 0 | | 3, 4

This aggregate line shows the following information:

• Class value: 1• Class name: Rural• RGB color: Red-0 Green-204 Blue-0• Description: None• Input class codes: Classes 3 and 4 were combined

to create the aggregate.

Starting an aggregate session

Once an aggregate session file is saved, you can open itusing the Load command in the Aggregate Classes area.

1. From the Aggregate dialog box, click ClassInitialization in the Aggregate Classes area.

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2. In the Class Initialization dialog box, click the TextFile tab.

3. Click Text File.4. In the File Selector dialog box, locate and select

the aggregate text file, and click Open.

If you want to overwrite the aggregate class, enablethe Overwrite existing classes check box.

5. Click OK.

Importing other classes

The Load command and the Class Initialization dialogbox can be used to:

• Import other channels from the same or a differentfile. In this way, you can add new classes to theaggregates list, which may include classes fromother classification results that you want to includein the present classification.

• Initialize a new set of classes for an aggregationsession. You import entries for the Input Classestable from either a classification channel or a .txtfile.

1. From the Aggregate dialog box, click ClassInitialization in the Aggregate Classes area.

2. In the Class Initialization dialog box, click theChannel tab.

3. Click File.4. In the File Selector dialog box, locate and select

the file containing the channel with the classes youwant to import, and click Open.

5. Select a classification channel from the Channelsavailable list.

You can edit any of the following fields in the tablefor the selected channel:

6. Value7. Name8. Color9. Description

If you want to replace all current classes, enable theOverwrite existing classes check box.

10. Click OK.

Setting up for class labelling

Class editing and aggregation both honour any sessioninformation present, but work equally well without it. Allother tasks including class labelling and accuracyassessment need an open session.

To open a session

1. From the Analysis menu, click ImageClassification and then click Post ClassificationAnalysis and then click Class Labelling.

2. From the File Selector dialog box, locate and selecta file, and click Open.

To open the Class Labelling dialog box in anopen session

1. From the Maps tree, right-click ClassificationMetaLayer and click Post-classification Analysisand then click Class Labelling.

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To set up for labelling

1. From the Channel Setup dialog box, select aclassified channel from the Channels available list.

2. Click OK.

About the Class Labelling dialog box

The Class Labelling dialog box lets you examine andmodify the characteristics of any class within a thematicchannel. You can change the class information such asthe value, name, color, or description, but the image datais not altered.

You can create a new class in the table of the ClassLabelling dialog box. For each new class, Focusgenerates an ID, value, class name, and color.

File and Channel:

The file name and channel are listed at the top of thedialog box.

Class Table:

All of the classes for the selected channel are listed in aclass table. For each class, the following is reported:

• Value• Name• Color• Description

Unsupervised:

Class labelling is normally done after an unsupervisedclassification, since the class values, names, and colorshave not been previously assigned.

Supervised:

You can use the Class Labelling dialog box after asupervised classification to:

• Re-label characteristics that were labelledincorrectly in the Training Site Editor beforeclassification.

• Label items that were not labelled prior to theclassification step for whatever reason.

• Add a level of transparency.• Add a more detailed description.

You can change any of the items in the table. To keep achange, click Save.

To change a class name

1. Double-click class name you want to edit.2. Type a name and press Enter.

To change a class color

1. Click a color in the Color column for a class.2. In the Color dialog box, choose a color from the

Basic Colors palette.3. Adjust the color as appropriate.4. Click OK.

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To change or add a class description

1. Click in the Description column for a class.2. Type a description as appropriate.

To create a new class in the table

1. In the Class Labelling dialog box, click New.

The new class is displayed as the last entry in thetable.

To delete a class

1. In the Class Labelling dialog box, select a class.2. Click Delete.

To initialize a class

1. In the Class Labelling dialog box, select a class.2. Click Class Initialization.

Class Initialization dialog box appears.

To save changes

1. Click Save.

Initializing classes from a classificationchannel

Initializing a new set of classes for a class labellingsession is done using the Class Initialization dialog box.You can import entries for the class table from aclassification channel.

1. From the Class Initialization dialog box, click theChannel tab.

2. Click File.3. In the File Selector dialog box, locate and select

the file containing the channel whose classes youwant to import, and click Open.

4. In the Class Initialization dialog box, select aclassification channel in the Channels availablelist.

If you want to replace all current classes, enable theOverwrite existing classes check box.

5. Click OK.

Initializing classes from a text file

Initializing a new set of classes for a class labellingsession is done using the Class Initialization dialog box.You can import entries for the class table from a text file.

Text file format

Class or aggregate details are stored as .txt files. Toimport this information, it must conform to a singlerecognizable format. The file is limited to one class perline and has seven fields delimited by a | character:

Value | Name | Red | Green | Blue | Desc |AssociatedDesc

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• Value is an integer representing the class code.• Name is a character string containing the class

name.• Red is a number between 0-255 depicting the red

component of the RGB color.• Green is a number between 0-255 representing the

green component of the RGB color.• Blue is a number between 0-255 representing the

blue component of the RGB color.• Desc is a character string that provides a

description for the class.• AssociatedDesc is only used in an Aggregation

session. It contains the description of the originalinput classes that are associated with theaggregate.

The following is an example of a text file that containsthree classes:

1|Water|0 |0 |255| Water class| |

2|Crop |0 |255|0 |Crops| |

3|Other|255|0 |0 |Water class| |

1. From the Class Initialization dialog box, click theText File tab.

2. Click Text File.3. In the File Selector dialog box, locate and select

the file containing the classes you want to import,and click Open.

If you want to replace all current classes, enable theOverwrite existing classes check box.

4. Click OK.

Launching the Accuracy Assessment dialogbox

Accuracy assessments determine the correctness of theclassified image, which is based on pixel groupings.Accuracy is a measure of the agreement between astandard that is assumed to be correct and an imageclassification of unknown quality. If the imageclassification corresponds closely with the standard, it issaid to be accurate.

To launch the Accuracy Assessment dialog box

1. From the Analysis menu, click ImageClassification and then click Post ClassificationAnalysis and then click Accuracy Assessment.

2. In the File Selector dialog box, locate and selectthe file containing the classified channel you want tocheck for accuracy, and click Open.

To open the Accuracy Assessment dialog boxduring classification

1. From the Maps tree, right-click ClassificationMetaLayer and click Post-classification Analysisand then click Accuracy Assessment.

Using the Accuracy Assessmentdialog boxThe Accuracy Assessment dialog box contains three

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areas:

Operations

• Select Classified Image• Load Reference Image• Generate Random Sample• Samples from Vectors• Accuracy Report• Clear Sample List

Assign Reference Class to Sample

This area contains a table listing all the categories in theselected classified image. The assignment of class andname values to the test pixels is based upon the entriesin this table.

Random Sample List

This area contains an information table for all therandomly generated test pixels.

Selecting a classified image

1. From the Accuracy Assessment dialog box, clickSelect Classified Image.

2. In the Select Classified Image dialog box, select asupervised classification channel from theChannels available list.

3. Click OK.

Selecting a reference image

1. From the Accuracy Assessment dialog box, clickLoad Reference Image.

2. In the Load Reference Image dialog box, selecteither one or three image channels from theChannels available list.

If you choose only one channel, select a PCTsegment from the PCTs availablelist.

3. Click OK.

Generating a random sample

The Generate Random Sample dialog box generates aset of random test pixel locations within the classifiedimage. This dialog box consists of two areas:

Number of Samples

Provides a spin box for specifying the number of randomsamples to generate.

Options

Sets the following sampling control options:

Stratify Samples to Class Percentages check box

• Enable this check box to randomly choose thenumber of samples from each class that areproportional to the percentage of the imageoccupied by each class. In other words, largerclasses contain more samples than smaller classes.

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Include only existing classes check box

• Enable this check box to generate random samplesonly for classes in the reference class list.

1. From the Accuracy Assessment dialog box, clickGenerate Random Sample.

2. In the Generate Random Sample dialog box, entera value for the number of sample points from theNumber of samples spin box.

If you want to randomly choose the number ofsamples from each class that are proportional to thepercentage of the image occupied by each class,enable the Stratify Samples to class percentagescheck box.

If you want to generate random samples only forclasses in the reference class list, enable theInclude only existing classes check box.

3. Click OK.

Assigning a reference class to a sample

1. From the Accuracy Assessment dialog box, selectthe first sample in the Random Sample List.

The cursor automatically moves to the samplelocation in the view pane. Compare this location tothe reference class table.

2. Select the class in the Assign Reference Class toSample table to which you think the random samplebelongs.

3. Click Transfer.

Opening samples from a vector segment

Imports your own random test points from a vectorsegment. The random pixel locations are added to theexisting list of sample points displayed in the RandomSample List. In this way, you can merge samples fromseveral sources.

1. From the Accuracy Assessment dialog box, clickSamples from Vectors.

2. In the Samples from Vectors dialog box, select avector segment from the Vector segmentsavailable list.

3. Select a reference attribute from the Referenceattributes list.

4. Select a class attribute from the Class Attributelist.

5. Click OK.

Launching the Accuracy Report dialog box

You can use the Accuracy Report dialog box oncereference classes are assigned to the random samples.Accuracy is determined by comparing the assignedreference value for each test pixel to the category in theclassification image.

To generate a report, it is not necessary to assign areference class to every random sample; however, aclassified image must be previously selected.

• From the Accuracy Assessment dialog box, clickAccuracy Report.

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The Accuracy Report dialog box creates three types ofaccuracy reports:

• Sample Report Listing: Shows which samples arecorrectly classified.

• Error (Confusion) Matrix: Displays the results ofthe accuracy assessment process. Reference datalisted in the columns of the matrix represents thenumber of correctly classified samples.

• Accuracy Statistics: Lists different statisticalmeasures of overall accuracy and accuracy for eachclass.

Producing a random sample report

1. From the Accuracy Report dialog box, click theSample Report Listing tab.

2. Click Generate Report.

Producing an error report

1. From the Accuracy Report dialog box, click theError (Confusion) Matrix tab.

If you want to apply a 3 x 3 mode filter to each testpixel location in the classified image, enable theApply Mode filter to classified values check box.The result of the mode filter operation are comparedto the reference value in order to access itsaccuracy.

2. Click Generate Report.

Producing an accuracy statistics report

1. From the Accuracy Report dialog box, click theAccuracy Statistics tab.

If you want to apply a 3 x 3 mode filter to each testpixel location in the classified image, enable theApply Mode filter to classified values check box.The result of the mode filter operation are comparedto the reference value in order to access itsaccuracy.

2. Click Generate Report.

Saving an accuracy report

You can only save a report from the current tab. You canappend the reports to the same text file. A text file canalso be overwritten with the report from the current tab.

To save an accuracy report

1. From the Accuracy Report dialog box, click SaveReport.

2. In the Save Accuracy Report dialog box, clickBrowse.

3. In the File Selector dialog box, locate and select afile, and click Open.

If you want to append the report to the selected file,click Append.

If you want to overwrite the report in the selected

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file, click OK.

To clear all the samples in the Random SampleList

1. From the Accuracy Assessment dialog box, clickClear Sample List.

To save a classification project

1. From the File menu, click Save Project.2. In the File Selector dialog box, locate and select a

folder where you want to save the project.3. Enter a project name in the File name box.4. Click Save.

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Chapter 6Information toolsInformation tools include histograms, image statistics,digital number (DN) profiles or sections of an image, andscatter plots. These tools do not change or processimages, but do allow you to get a better understanding ofthe data you are using. Information tools, such as imageband correlation statistics and histogram statistics, helpyou decide how you can further process image data.

Opening the Information report

You can display the individual attributes of selectedfeatures for rasters, vectors, and charts using theInformation Report.

For raster files, the Information Report provides the digitalnumber (DN) values for the pixel identified by the cursorposition. If an RGB file is used, the report includes theDN values for the red, green, and blue layers. TheInformation Report can also be used for grayscale orpseudo-color rasters. In these cases, only one DN valueis reported.

For vector files, the Information Report displays vectorattributes. The report provides all attributes for a selected(under-the-pixel) vector.

For charts, the Information Report displays attributes forthe record corresponding to selected data in a chart.

1. From the Tools toolbar, click the Informationbutton.

The Information Report appears.

You can use the Information Report with both raster andvector data.

Viewing information for a selectedvector

1. From the Information Report, enable the Selectedshapes option in the Report on area.

2. On the Editing toolbar of the Focus window, clickthe Selection Tools arrow and choose Individual.

3. In the view pane, click a vector.

The attribute information for the selected vectordisplays in the Information Report.

You can also select several vectors at once. With severalvectors selected, you can change the vector displayed inthe Information Report. The cursor automatically movesto the current vector in the view pane.

Viewing information for vectors underthe cursor

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1. From the Information Report, enable the Entriesunder cursor option in the Report on area.

2. In the view pane, click a vector.3. On the Editing toolbar, click the Selection Tools

arrow and choose Individual.4. In the view pane, click a vector shape or segment.

The Information Report shows the details of theselected vector.

Showing information for raster data

1. Ensure that the raster data is opened in the viewpane.

2. From the Information Report, enable the Entriesunder cursor option in the Report on area.

3. In the view pane, click a feature.

The Information Report shows the DN values for the pixelof the selected feature for the top raster layer in the Mapstree.

If multiple raster layers are open in the Maps tree, youcan scroll between the DN values for the specified pixelin each of the layers by clicking the arrows in the Recordarea of the Information Report.

All features, both visible and invisible, are reported byclicking a location in the view pane. You can showinformation for a new record in the current layer with theRecord arrow buttons in the Information Report.

Displaying the attributes from a chart

1. In the Chart viewer, click the Identification button.2. Click a piece of data in the chart.

The attributes for that record display under Values.

Specifying the units of measurement

The Measure tool reports length, area, and perimetermeasurements of areas within imagery in the view pane.It allows you to draw areas and lines in several differentways, while reporting in the units of measure you choose.

1. With a file open, click the Measure arrow andchoose one of the following menu options:

• Linear Units: displays units for a linearmeasurement

• Area Units: displays units for an areameasurement

• Angle Units: displays units for an angle2. Choose a unit of measurement from the

corresponding menu option.

A check mark next to a unit of measurementindicates it has been selected.

Selecting a Measure tool

1. With a file open, click the Measure arrow andchoose one of the following menu options:

• Line: lets you measure a linear object

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• Polygon: lets you measure a polygonal object• Rectangle: lets you measure a rectangular

object• Ellipse: lets you measure an elliptical object

Measuring a line

1. With a file open, click the Measure arrow and clickLinear Units.

2. Choose a unit of measurement.3. Click the Measure arrow and choose Line.4. In the view pane, click where you want to begin

measuring.5. Move the cursor to the end of the measurement

area.

If you want to continue measuring in a differentdirection, click where you want to change directionand continue measuring.

The total length, segment length, and azimuthappear at the bottom of the view pane.

If you want to stop measuring, double-click the viewpane.

Measuring a polygon

1. With a file open, click the Measure arrow and clickArea Units.

2. Choose a unit of measurement.3. Click the Measure arrow and choose Polygon.4. In the view pane, click where you want to begin

measuring.5. Click the next polygon vertex.

Repeat this as necessary until you have at leastthree vertices in the polygon. The area andperimeter of the polygon appear at the bottom of theview pane.

If you want to stop measuring, double-click the viewpane.

Measuring a rectangle or ellipse

1. With a file open, click the Measure arrow and clickArea Units.

2. Choose a unit of measurement.3. Click the Measure arrow and choose one of the

following options:• Rectangle• Ellipse

4. In the view pane, click where you want to beginmeasuring.

For a rectangle, the starting point is a corner of themeasurement area. For an ellipse, start at thecenter of the measurement area.

5. Drag the rectangle or ellipse to cover the area youwant to measure.

The area and perimeter of the rectangle or ellipseappear at the bottom of the view pane.

If you want to stop measuring, double-click the viewpane.

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Reading the Measure tool report

Focus provides a report to help you keep track of yourimage measurements. You activate the MeasurementTool Report from the Options dialog box in the Toolsmenu. (See Measurement tools on page 112 ) When theMeasurement Tool Report is active, the report windowopens each time you take a measurement in the viewpane.

Information appearing in the Measurement Tool Reportdepends on the measurement tool you are using.Information is shown as either a linear or polygonalmeasurement. (See Specifying the units of measurementon page 206 )

Line Measure Reports:

Reports a measurement for each segment of a line thatincludes the length, azimuth, and start and endcoordinates.

Polygon Measure Report:

Reports the area, perimeter, and coordinates for eachpoint in the polygon. For ellipse measurements, thereport shows the perimeter and the area only.

Viewing histograms and statistics

Histograms graphically represent the count of each pixelvalue in an entire or a selected region of a raster. Thestatistical information that you obtain from the pixel

values can help you in your analysis of a geographicalarea.

You can access both histograms and statistics from theraster maps layer, and access the statistics from the file’sraster.

1. In the Maps tree, select a raster map layer.2. In the Focus view area, use the Zoom tools to select

the area for which you want to view a histogram.3. From the main menu, click Layer and then click

Histograms.

The Multi Histogram Display window appears if anRGB map layer is selected, otherwise, theHistogram Display window appears.

4. Proceed to Viewing a histogram on page 208 .

Viewing a histogram

You can view a histogram of a grayscale, pseudo-color,or an RGB map layer.

A histogram of the currently viewed area is firstdisplayed. For an RGB map layer, a histogram isdisplayed for each RGB channel. At a glance, you canview the distribution of pixels and then select a histogramto view its statistics. For more information, refer toViewing histogram statistics on page 209 .

You can also view a histogram of a region that is under abitmap mask. For more information, refer to Viewinghistograms under a bitmap mask on page 210 .

1. In the Multi Histogram Display or Histogram

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Display window, click a histogram to view thehistogram statistics and other details.

The Histogram with Statistics window appearsdisplaying the histogram of the content currentlyviewed in the Focus viewer.

2. Proceed to Viewing histogram statistics on page 209 .

Viewing histogram statistics

You can view statistics of a histogram that represent anentire raster, a region under a bitmap mask, or thecurrent view displayed in the Focus viewer. You can alsozoom into or out of the raster in the Focus viewer andwatch the histogram in the Histograms with Statisticswindow change accordingly. To view histogram statisticsof a region under a bitmap mask, refer to Viewinghistograms under a bitmap mask on page 210 .

In addition to viewing statistics, you can zoom intoportions of the displayed histogram, print, or export thehistogram in its zoomed or original version. For moreinformation, refer to Zooming into and out of a histogramon page 210 ,Printing a histogram on page 210 , andExporting a histogram on page 210 .

1. Perform one of the following steps:• In the Maps tree, perform steps in Viewing a

histogram on page 208 .• In the Files tree, right-click a raster channel

and select Histogram with Statistics.

The Histgogram with Statistics window appears.

2. In the Histogram with Statistics window, move themouse pointer over the histogram to view the

current count of pixels for a given pixel value.

The Statistics section provides you with furtherstatistical information about the histogram.

3. If required, in the Pixel Value and Pixel Countfields, enter values of a particular area of thehistogram. Press Enter.

The histogram view displays the portion of thehistogram that corresponds to the specified values.

4. If required, click Zoom to Overview to revert to theoriginal histogram view. For information about Maskcontents, refer to Viewing Mask contents on page 209.

Viewing Mask contents

You can view three types of histograms from the Masklist box in the Histogram with Statistics window:

• Entire raster view: displays a histogram of the entireraster.

• Current view area: displays a histogram of the areathat is displayed in the Focus viewer. If you arezoomed in closer than 1:1, the actual data pixels areused. If you are zoomed out further than 1:1 thedata pixels are approximated by using the renderedimage.

• Bitmap layer: displays a histogram of a region undera bitmap mask.

1. Perform one of the following steps:• In the Maps tree, perform steps in Viewing a

histogram on page 208 .• In the Files tree, right-click a raster channel

and select Histogram with Statistics.

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2. In the Histogram with Statistics window, select anoption from the Mask list box.

When accessed from the Maps tree, the Mask listbox displays the entire raster, current view, and anybitmap layers that are in the current area. Thebitmap layers are listed whether they are saved ornot. When accessed from the Files tree, the Masklist box displays the entire raster and the bitmaplayers that are saved in the same, active source file.The saved bitmap layers are listed with their file andlayer names displayed. For more information aboutviewing histograms for a bitmap layer, refer toViewing histograms under a bitmap mask on page 210.

Viewing histograms under a bitmap mask

You can view histograms for regions that have beendefined by bitmap masks. You must first create bitmaplayers and then apply bitmap masks for the regions. Formore information, refer to Creating a new bitmap layer onpage 141 and Creating a mask on page 228 .

1. In the Histogram with Statistics window, selectthe bitmap mask from the Mask list box.

When viewing from the Maps tree, bitmap layers forwhich masks have not been applied are also listedin the Mask list box. If you select one of these layersand then apply a mask to a region in the Focusviewer, the Histogram with Statistics windowrefreshes with the relevant histogram.

Zooming into and out of a histogram

You can zoom into an area of a histogram that isdisplayed on the Histogram with Statistics window to viewmore detailed pixel values.

1. In the Histogram with Statistics window, positionthe cursor over the area of the histogram you wantto zoom into.

2. Right-click and select Zoom In or drag a rectangle.

You can click Zoom Out to revert to the previousview of the histogram and Zoom to Overview torevert to the original histogram.

Printing a histogram

You can print the displayed histogram or its zoomedversion.

1. In the Histogram with Statistics window, selectFixed aspect ratio in the Options section, ifrequired.

2. In the Background list box, select a backgroundcolor for the histogram.

The selected color appears behind the histogram.

3. Click Print and specify the printer settings.4. Click Print.

Exporting a histogram

You can export the displayed histogram or its zoomedversion to a file.

1. In the Histogram with Statistics window, click

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Export.

The File Selector window appears.

2. Specify the file name, format, and location.3. Click Save.

Working with numeric valuesThe Numeric Values dialog box is an information tool thatprovides a numeric version of the digital number (DN)values in an image. The DN values for each band in anRGB image are displayed concurrently. The numericinformation lets you explore relationships between DNvalues in different image bands at a specific pixellocation. (See Opening the Numeric Values dialog box onpage 211 )

Opening the Numeric Values dialog box

The Numeric Values dialog box allows you to workdirectly with the pixel values in raster data. You can viewand edit the individual pixel values for grayscale andRGB channels through individual tables. Each tableprovides a sample of values that correspond to the cursorcoordinates in the view pane. You can change thesample of values by moving the cursor across the viewpane. You can also switch the values to show either rawor enhanced data. Red, green, and blue pixel values areshown in separate tables.

Raw Data:

Switches numeric values to raw data values.

Enhanced Data:

Switches numeric values to enhanced data values.

Line Numbers:

The gray column on the right of a numeric values tableshows the numbers for each line in an image.

Pixel Numbers:

The gray row at the top of a numeric values table showsthe numeric value for a single pixel.

Red Channel Value:

The red pixel value for a selected pixel in the view pane.A red channel value is indicated by a red border in thenumeric values table.

Green Channel Value:

The green pixel value for a selected pixel in the viewpane. A green channel value is indicated by a greenborder in the numeric values table.

Blue Channel Value:

The blue value for a selected pixel in the view pane. Ablue channel value is indicated by a blue border in thenumeric values table.

1. In the Maps tree, select an RGB layer.2. From the Layer menu, click Numeric Values.

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You can export digital number (DN) values to a text filefor further statistical analysis. You can also use theNumeric Values dialog box to change the DN values inan image.

Exporting the numeric values to a text file

1. From the Numeric Values dialog box, click Export.2. In the File Selector dialog box, locate and select a

file.3. Click Save.

(See Interpreting the values on page 212 ).

Change a color channel DN value

The digital number (DN) values of an image channel canbe altered directly. Only the image channels that arecurrently displayed can be altered.

1. In the Numeric Values dialog box, double-click thecell for the image layer and pixel location that youwant to edit.

2. Type a value (between 0 and 255 for RGB) andpress Enter.

Note: You cannot alter enhanced values.

(See Interpreting the values on page 212 )

Interpreting the values

The Numeric Values dialog can be expanded to displaymore values. Each table displays one color-highlightedcell containing the RGB value of a selected pixel/linecoordinate. The other cells contain the RGB values of thesurrounding pixel/line coordinates. RGB values show theposition of the cursor in the view pane.

Raw and Enhanced Data

The Numeric Values dialog box allows you to view thedigital number (DN) values for both raw and enhancedDN values. The raw data values represent the DN valuesthat are read directly from the image file. The enhanceddata values represent the DN values as they are currentlydisplayed in the view pane. For more information onenhanced data values. (See Changing a defaultenhancement on page 244 )

To display the RGB values for raw or enhanced data,enable the appropriate option.

Making an image profile

Image profiles show the spectral response of a selectedfeature along a user-specified cross-section. You cangenerate a spectral plot and a numeric values table fromRGB or grayscale input channels along a user-definedvector.

There are several instances where you can use an imageprofile. Your work will determine when and where youshould use one. Following are examples where profileshave been used effectively.

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Profiling can give you an idea of the spectralhomogeneity for a feature. If profiles taken across afeature are all relatively flat, the feature is consideredhomogeneous for the particular wavelength in which theprofile is taken. Relatively flat profiles indicate that aparticular wavelength channel is a good input for asubsequent supervised classification where the extractedfeatures are being investigated.

As another example, you may want to establish apotential correlation between a characteristic of a featurein the scene and its spectral response. Such a correlationcould be used in an image from the Coastal Zone ColorScanner (CZCS) satellite.

The CZCS satellite measures important ocean propertiesfrom space. It was designed specifically to measure thetemperature and color of the coastal zones of the oceans.The CZCS operates in six wavelength regions (bands),including bands in the visible, near-infrared, and thermalregions of the electromagnetic spectrum. The four visiblebands are used to map phytoplankton concentrations andinorganic suspended matter, such as silt. Thenear-infrared channel can be used to map surfacevegetation, while the thermal channel can be used tomeasure sea surface temperatures.

You can use the Image Profile to examine changes inocean properties as a function of distance from thecoastline or along the perimeter of a coastline. You candemonstrate graphically how chlorophyll, temperature,suspended sediment, and gelbstoff (the yellow substanceof interest to marine researchers) vary along the coastalwaters in a CZCS image.

Drawn across a DEM, a profile will give information onhow the elevation changes from one point to another,giving a cross-sectional perspective of the terrain.

1. In the Maps tree, click an image layer.2. From the Layer menu, click Profile.

The vector profile is normally interpreted from left to right;however, if the end points of the vector occupy the sameX position, the profile is interpreted from top to bottom. Inthe event of a closed shape, the profile is interpreted in aclockwise direction from the start/end node of the closedshape.

The graph is a profile of the image layer and shows theinput channels plotted with the gray values on the Y-axis,and the distance along the vector on the X-axis. Thegraph demonstrates how the gray values change withdistance.

Gray Values

In the case of an 8-bit RGB image layer, the range of theY-axis is 0 to 255 and represents the 256 possiblegray-level values for each pixel of the red, green, andblue input channels.

Distance

The X-axis is measured in meters and represents thedistance between the end points of the vector. The rangeof the X-axis depends on the length of the vector and thescale of the area or the ground distance covered by theimage.

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Using the mensuration bars

You can change the viewable range for both the X and Yaxes, export the plot to a graphic file, change thebackground color for the plot, and print the plot.

1. From the Profile Table, click Options.2. In the Profile Options dialog box, click in the

Current Channel column for a channel for whichyou want use the measuring tools.

A red X indicates the channel is selected.

3. In the Profile Graph, drag the sliding bars to theregion you want to measure.

Selecting vector profiles

If a vector is not selected, a simple line is automaticallygenerated and used to calculate the profile. As analternative, you can create a vector or select an existingvector for the profile. To modify the profile vector, use theLine Color editor or Vector Editing toolbar.

1. Draw or select an existing vector layer.2. With either the Selection Tool cursor or the Vector

Editing cursor, select the line in the view pane.

The values change in the Profile Table and the lineis updated in the Profile Graph.

Using the spectra extraction toolsYou can extract spectra from image data usingmultispectral or hyperspectral data. You begin spectra

extraction by configuring your data with the SpectraExtraction Configuration dialog box. Focus creates ahyperspectral metalayer to hold the extracted spectra.You must first specify the input file and channels youwant to work with. You can select an existing channel oryou can create a new one. (See About the SpectraExtraction Configuration dialog box on page 215 )

When you begin with no open data, the SpectraExtraction Configuration dialog box automatically createsa new Map and Area for your work. If a Map and an Areaare already open in and the input file has the samegeoreferencing as the Area, a new metalayer is added tothe Map and Area. When georeferencing is incompatible,a new Area is added to the existing Map.

When you have configured a metalayer, you can accessboth the Scatter Plot and Spectra Plot dialog boxes froma menu in the Spectra Extraction dialog box. Scatter plotsand spectra plots are automatically linked to the data youspecify in the Spectra Extraction dialog box. (SeeExtracting spectra from a region of interest on page 215 )

The Spectra Extraction tools let you:

• Collect regions of interest from a hyperspectralimage or a scatter plot.

• Review mean and ellipse information in a scatterplot for your spectra.

• Create and review spectra plots from a region ofinterest.

• Compare spectra signatures of regions withreference spectra from either a spectra library oranother image.

• Save spectra to either an XLS or to an SPL library.

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Extracting spectra from a region of interest

You can define regions of interest manually in the viewpane using the drawing tools and derive spectralsignatures for them. You can manually create regions ofinterest using the New Shapes tool. The resultingspectral end members can be used as input into spectralprocessing algorithms for image classification andspectral unmixing.

Hyperspectral spectra extraction provides linkingbetween image regions of interest, scatter plots, spectraplots and spectral libraries. (See Configuring ahyperspectral metalayer on page 215 )

About the Spectra Extraction Configurationdialog box

The Spectra Extraction Configuration dialog box lets youselect input channel data and choose a bit depth for youroutput data.

Input:

Lets you enter a file name and location or browse for thedata you want to use as input.

Browse:

Opens the File Selector dialog box, where you can locateand select input data.

Region of Interest Channel:

Lets you create a region of interest by either selecting alayer from the input data or creating a new layer. You canalso set the bit-depth of a new layer.

Layer:

Lets you choose a layer from an input data file or create anew layer.

Type:

Lets you choose a bit-depth for a new layer.

Accept:

Opens the Spectra Extraction dialog box and transfersthe settings you made in the Spectra ExtractionConfiguration dialog box.

(See About the Spectra Extraction dialog box on page 216).

Configuring a hyperspectral metalayer

During spectra extraction configuration, a metalayer iscreated in the Files tree. When you right-click a newmetalayer in the Maps tree, you open a sub menu withcommands for the Spectra Extraction Configurationdialog box, the Spectra Extraction dialog box, the SpectraPlotting dialog box, and the Scatter Plot dialog box. Youcan link between the image and a region of interestdefined by a mask layer and work with scatter plots andspectra plots.

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Metalayer analysis is based on wavelength metadata.Files must be either .pix format or linked to a .pix file.The region of interest channel must be added to a .pixfile when using compressed data.

1. From the Analysis menu, click Spectra Extraction.2. In the Spectra Extraction Configuration dialog

box, choose an input file from the Input list box.

If no file is available, click Browse, locate andselect a file in the File Selector dialog box, andclick Open.

3. In the Region of Interest Channel area, choose aregion of interest channel from the Layer list box.

If you want to change the bit depth of the layer,choose one from the Type list box. You must selecta channel type if you are creating a new layer.

4. Click OK.

(See About the Spectra Extraction Configuration dialogbox on page 215 ).

About the Spectra Extraction dialog box

The Spectra Extraction dialog box displays the channelsin the regions of interest in a table and is linked to theSpectra Plotting dialog box. The spectra table lists thechannels used to generate endmember or samplesignatures from selected pixels within a region of interest.You can either choose a channel as a region of interestor create a new channel and draw a bitmap mask overthe region in the view pane.

The Spectra Extraction dialog box lets you specify detailsfor a region of interest, edit the spectra list in the spectratable, change spectra attributes, and adjust layer opacity.

(See Region menu on page 216 )

Region menuThe Region menu has options for adding spectrachannels, importing bitmap and vector layers, mergingchannels, and exporting channels to create new files.

New:

Adds a new channel to the spectra table.

Import:

Lets you import vector or bitmap data to the spectratable.

Vectors:

Allows you to import vector regions from an existingvector segment for regions of interest and opens theImport Vectors dialog box. (See About the Import Vectorsdialog box on page 218 )

Bitmaps:

Allows you to import bitmaps from an existing bitmaplayer for regions of interest and it opens the ImportBitmaps dialog box. (See About the Import Bitmaps

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dialog box on page 219 )

Merge:

Allows you to merge multiple regions of interest that youselect from a source region and opens the MergeClasses dialog box. (See Merging a spectra channel onpage 220 )

Export Regions to Bitmaps:

Lets you export a region to a bitmap.

(See Edit menu on page 217 )

Edit menu

The Edit menu has options that let you clear and deletethe channels listed in the spectra table.

Clear Selected:

Clears a channel selected in the spectra table.

Clear All:

Clears all of the channels listed in the spectra table.

Delete Selected:

Deletes a channel selected in the spectra table.

Delete All:

Deletes all of the channels listed in the spectra table.

(See Tools menu on page 217 )

Tools menu

The Tools menu lets you access the Scatter Plot dialogbox and the Spectra Plotting dialog box, and savesspectra to a Spectra Library.

Scatter Plot:

Opens the Scatter Plot dialog box. (See Viewing thescatter plot for a layer on page 232 )

Spectra Plot:

Opens the Spectra plotting dialog box. (See Plottingspectra on page 221 )

Save Spectra Signatures:

Opens the Save Spectra to Library dialog box. (SeeSaving a spectra plot on page 226 )

(See Spectra extraction table on page 217 )

Spectra extraction table

The Spectra Extraction table lists spectra and lets youchange several attributes in the table cells.

Value:

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Lets you change the channel value for a channel listed inthe table.

Name:

Lets you enter a new name for a channel.

Color:

Shows the color of the bitmap layer for the channelshowing in the view pane.

Plot Mean:

Lets you include the plot mean information with thespectra channel when you save the spectra extractioninformation.

Plot Ellipse:

Lets you include plot ellipse information with the spectrachannel when you save the spectra extractioninformation.

Description:

Lets you enter and edit a brief description for the spectrachannel.

Opacity:

Lets you set an opacity value for the spectra bitmap. Anopacity value of 100% makes the spectra bitmap

completely opaque. No underlying imagery is visible. Anopacity value of zero makes the bitmap invisible.Underlying imagery is completely visible.

Apply:

Applies any changes you make with the Opacity slidecontrol to the image in the view pane.

Save and Close:

Closes the Spectra Extraction dialog box and saves thechanges you have made.

Save:

Saves the changes you have made but leaves theSpectra Extraction dialog box open.

About the Import Vectors dialog box

The Import Vectors dialog box lets you select vectors andchoose the attributes you want to import to the SpectraExtraction dialog box.

File:

Opens the File Selector dialog box, where you canchange the source files from which to import vector data.

Destination Class:

Reports the region you have selected in the Spectra

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Extraction dialog box to which you are importing vectors.

Segment:

Lists the ID for a segment in the source data.

Interior Points:

Lets you include interior point data with the importedvectors.

Polygon Boundary:

Lets you include polygon boundary data with theimported vectors.

Field:

Lets you choose the attribute you want to include with theimported vectors.

Description:

Shows the descriptions for the vectors from the sourcefiles.

Rasterize:

Uses the data and information you have set in the ImportVector dialog box and imports it to the Spectra Extractiondialog box as rasterized data.

About the Import Bitmaps dialog box

The Import Bitmaps dialog box lets you choose bitmapsfrom your source data and import them to the SpectraExtraction dialog box.

Import As:

Lets you import a raster as a new channel in the SpectraExtraction dialog box or import it as the channel you haveselected in the Spectra Extraction dialog box.

New Class:

Imports the raster and adds it to the Spectra Extractiontable.

Current:

Imports a raster as the channel you have selected in theSpectra Extraction dialog box.

Bitmap List Window:

Lets you import the available bitmaps in the source data.

Overwrite existing training areas:

Lets you overwrite a selected channel in the SpectraExtraction dialog box.

Import:

Imports the selected rasters to the Spectra Extractiondialog box.

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Merging a spectra channel

The Merge Classes dialog box lets you merge theattributes of one channel listed in the Spectra Extractiondialog box into another channel in the list.

Select Source Classes:

Reports the value, name, color, and description of theavailable source channels.

Value:

Reports the channel value for a channel listed in thesource table.

Name:

Reports the name of a source channel.

Color:

Shows the color of the source bitmap.

Description:

Reports the description for the source spectra channel.

Select Destination Classes:

Reports the value, name, color, and description of theavailable destination channels.

Value:

Reports the channel value for a channel listed in thedestination table.

Name:

Reports the name of a destination channel.

Color:

Shows the color of the destination bitmap.

Description:

Reports the description for the destination spectrachannel.

1. In the Spectra Extraction dialog box, click Regionand then click Merge.

2. In the Merge Classes dialog box, choose a sourcechannel from the Select Source Classes table.

3. In the Select Destination Classes table, choose adestination channel.

4. Click Merge.

Saving a spectral extraction

The Save Spectra Signatures dialog box lets you choosethe files and spectra you want to save to the Spectralibrary.

1. Choose a file from the File list box.

If no file is listed, click Browse, locate and select a

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file in the File Selector dialog box, and click Open.

2. Choose a mask to exclude any bitmap segmentfrom the Spectral Extraction file from the Mask listbox.

3. Enable one of the following Spectra Rangesoptions:

• Channel # expresses spectra ranges inchannels (bands) 1, 2#100

• Wavelength # expresses the spectra rangesin wavelengths (800um#12,000um)

4. Type a range based on the selected spectra rangetype in the Range Value box.

For example, if a spectra range is for a channel, anentered range of 5, -20, 30, -40 will yield spectrumtaken from channels 5 to 20 and channels 30 to 40;if spectra range is for a wavelength, an enteredrange of 800, -1200, 1400, -2000 will yield spectrumtaken from a wavelength of 800um to 1,200um anda wavelength of 1,400um to 2,000um.

5. Enable any of the following check boxes:• Save selected Spectra only # saves only the

spectra that you have selected• Save ROIs to Bitmap layers # saves the

spectra as a bitmap layer6. Click Save.

Plotting spectra

You can plot spectra with an interactive graph tool thatcan be used independently or with the spectra extractiontools allowing you to compare the signatures from aspectra library with the spectra in your regions of interest.

1. From the Maps tree, select a layer.2. From the Layer menu, click Spectra Plot.

(See About the Spectra Plotting dialog box on page 221 )

About the Spectra Plotting dialog boxThe Spectra Plotting dialog box allows you to view andconfigure a detailed graph that plots radiometric quantityand wavelength.You can import spectra from severalsources that include the cursor position in the view pane,a region of interest drawn in the view pane and listed inthe Spectra Extraction dialog box, and spectra signaturesfrom Spectra Library files.

There are several tools that let you control the datadisplay of the spectra you are plotting. You can show orhide the controls and then work with the graph values byzooming to any graph region along a plot line.

The Spectra Plotting dialog box controls include:

• Active Radiometric Quantity and Wavelength graph• Active Displayed Spectra table• Data controls• Hyperspectral Image adjustments• Plotting Range settings• Reports• Graph Options and settings

(See Radiometric quantity vs. wavelength graph on page 221)

Radiometric quantity vs. wavelength graph

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The Radiometric Quantity vs. Wavelength graph allowsyou to read radiometric and wavelength values for bothregions of interest and spectra library signatures in thesame graph. The X and Y scales can be adjusted usingthe Plotting Ranges and Graph Option controls. You canzoom to a region within the graph window by draggingyour mouse over the region you want to enlarge.

Library:

Measures radiometric quantities for spectra librarysamples.

Band Number or Wavelength [nm]:

Measures the band number or wavelength of both thelibrary samples and your source data. The the graphshows the unit of measure as Band Number orWavelength in nm depending on the presence ofradiometric transformation metadata in the sample data.When no transformation metadata is present, the valuesare shown as band numbers.

Image:

Measures radiometric quantities for the source data.

(See Displayed spectra on page 222 )

Displayed spectra

The Displayed Spectra table and controls lists the spectrasignatures available for viewing in the Spectra plot graph.

The table reports the spectra ID number, name, andcolor. The Displayed Spectra controls allow you to show,hide, and change the color of the spectra plot lines and tochoose new samples from a Spectra Library and newareas of interest.

ID:

Assigns a number to spectra signatures in ascendingchronological order.

Name:

Lists the names of each spectra signature.

Color:

Lists the plot line colors for each spectra signature in thetable. You can change the color of a signature plot line inthe graph.

Show:

Lets you show or hide a signature plot line.

From Spectra File:

Opens the Select Spectra From Library dialog box. Youcan change spectra libraries and choose more spectrasignatures. (See Selecting a spectra library on page 225 )

From Regions:

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Imports spectra listed in the Spectra Extraction dialog boxtable and makes them available for viewing in theSpectra Plotting dialog box.

From Image:

Imports spectra from the cursor position within the viewpane and adds the spectra values to the table, makingthem available for viewing in the Spectra Plotting dialogbox.

Clear Spectrum:

Clears a selected spectrum from the Display Spectratable.

Clear All:

Clears all of the spectra signatures listed in the DisplaySpectra table.

Save Spectra:

Opens the Save Spectra to Library dialog box, where youcan add a spectra to a Spectra library. (See Saving aspectra plot on page 226 )

Window Size Around Cursor:

Lets you choose a kernel size for the sample taken in theview pane at your cursor location.

Spectra Quantity to Sample:

When your data contains radiometric transformationmetadata, the transformed spectra are listed in theSpectra Quantity to Sample box. You can choose whichof the transformation quantities you want to sample fromthe list.

The possible radiometric transformations are:

• Uncalibrated digital number (DN) values• Non-physical adjustment• At-sensor (apparent) radiance• Scene radiance• Scene irradiance• Reflectance

Hyperspectral Image:

Let you work with hyperspectral image data.

Wavelength First:

Lets you adjust the starting wavelength value upwardfrom the default hyperspectral wavelength, read from thefile data.

Last:

Lets you adjust the last wavelength value downward fromthe default hyperspectral wavelength, read from the filedata.

Mask:

Allows you to choose bitmap masks in your source files.

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(See Graph options on page 224 )

Graph options

The Graph options allow you to change the way thegraph lines for the Spectra plot are shown.

Overlay:

Lets you show numbered scales on the graph for library,image, and wavelength values. Plot lines aresuperimposed so that the values can be compareddirectly.

Stack:

Shows a numbered scale for wavelength values only.Plot lines are separated so that the plot shapes can becompared.

Offset:

Lets you enter an offset for the graph plot lines.

(See Plotting ranges on page 224 )

Plotting ranges

The Plotting Ranges area lets you set several parametersfor a spectra plot.

Adjust Plot Range To Data:

Automatically adjusts the spectra plot to show all thevalues in the data.

X-axis Min:

Lets you enter a minimum range for the graph X-axis.

Max:

Lets you enter a maximum range for the graph X-axis.

Image Min:

Lets you enter a minimum range value for data plottedfrom the cursor position in the view pane.

Max:

Lets you enter a maximum range value for data plottedfrom the cursor position in the view pane.

Library Min:

Lets you enter a minimum range value for data plottedfrom a spectra library signature file.

Max:

Lets you enter a maximum range value for data plottedfrom a spectra library signature file.

Same As Image:

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Matches the graph values to the cursor values from theimage in the view pane.

(See Report on page 225 )

Report

The report area reports information for spectra signaturesselected in the Displayed Spectra table based on boththe entire spectra and on specific pixel/line coordinates.

Current Spectrum:

Reports the ID for a spectra selected in the DisplayedSpectra table.

Wavelength:

Reports the wavelength of a spectra selected in theDisplayed Spectra table.

Intensity:

Reports the intensity of a spectra selected in theDisplayed Spectra table.

Current Pixel:

Reports the pixel location.

Current Line:

Reports the line location.

Wavelength:

Reports the pixel wavelength value for the pixel/linelocation.

Intensity:

Reports the pixel intensity value for the pixel/line location.

Hide Controls and Show Controls:

Hides or shows all controls for the Spectra Plot panel.

Zoom In:

Zooms into the plot lines in the spectra plot graph.

Zoom Out:

Zooms out of the plot lines in the spectra plot graph.

Zoom Overview:

Zooms the plot lines in the spectra plot graph to anoverview showing the extents of the plotted values.

Selecting a spectra library

The Select Spectra From File dialog box lets you openspectra library files, choose spectra, and add them to thetable in the Spectra Plotting dialog box.

Spectra File:

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Lets you enter a spectra file from which to choosespectra signatures.

Browse:

Lets you find a spectra file from which you can select filesfor export to the Spectra Plotting dialog box.

Library window:

Lists the spectra contained in an open spectra file.

Add to Plot:

Exports the selected spectra in the list in the Librarywindow to the Spectra Plotting dialog box.

1. From the Spectra Plotting dialog box, click FromSpectra File.

2. In the Select Spectra From Library, choose alibrary file from the Spectral Library list box.

If no library file is listed, click Browse and locateand open a different spectra library file or folder.Spectra libraries use a .spl file name extension.

3. In the Spectra Library, select the spectra you wantto add to the Spectra Plotting table.

4. Click Add to Plot.

Changing the graph options

The Select Spectra From File dialog box lets you openspectra library files, choose spectra, and add them to thetable in the Spectra Plotting dialog box.

Spectra File:

Lets you enter a spectra file from which to choosespectra signatures.

Browse:

Lets you find a spectra file from which you can select filesfor export to the Spectra Plotting dialog box.

Library window:

Lists the spectra contained in an open spectra file.

Add to Plot:

Exports the selected spectra in the list in the Librarywindow to the Spectra Plotting dialog box.

1. Choose either Channel Number or Wavelengthfrom the X axis labelling list box.

2. Choose a wave record from the Wave record listbox.

3. Choose a number to represent the window sizefrom the Window size around cursor list box.

Saving a spectra plot

You can choose the files and spectra you want to save tothe spectra library.

1. Choose a file from the File list box.

If no file is listed, click Browse, locate and select afile in the File Selector dialog box, and click Open.

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2. Enable any of the following check boxes:• Save selected Spectra only: saves only the

spectra that you have selected• Save ROIs to Bitmap layers: saves the

spectra as a bitmap layer3. Click Save.

Opening the DEM Editing dialog box

Digital elevation models (DEMs) may contain pixels withfailed or incorrect values. You can edit a DEM to smoothout irregularities and create a more accurate model. Forexample, areas such as lakes often contain misleadingelevation values; setting those areas to a constant valueimproves the model.

For suggestions about how to correct commonirregularities, see Applying tool strategies for commonsituations in digital elevation models on page 230 .

1. From the Analysis menu, click DEM Editing.

Editing a DEM

1. From the DEM Editing dialog box, choose a DEMfrom the File list box.

If no DEM is available, click Browse and open a filefrom the File Selector dialog box.

2. Choose a layer that contains the DEM from theLayer list box.

3. Type the value assigned to pixels that have noelevation values because the image correlationfailed in the Failed box.

Some features are not accessible unless you entera failed value.

4. Type the value assigned to the area that lies outsidethe DEM in the Background box.

The background value can be a maximum orminimum value such as -150 or -999999. Somefeatures are not accessible unless you enter abackground value.

If you want to see the results without saving the newlayer, enable the Display option.

If you want to save the new layer in the project,enable Save option and choose a file from the Filelist box. Type a name for the new layer or select anexisting layer from the Layer list box.

If you want to display the results in the view pane,enable the Display saved results check box.

5. If you want to apply the edits repeatedly andachieve a cumulative effect on the data, enable theLoad results to input check box.

You can use a mask to identify specific areas that youwant to edit. The mask itself does not change the valuesin the area that it covers, but you can use the tools in theArea Fills Under Mask and Filtering and Interpolationareas to edit the data under the mask.

Opening an existing mask

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1. In the DEM Editing dialog box, click Open a MaskLayer.

To create a mask, see Creating a mask on page 228 .

To modify the values under the mask, seeReplacing the elevation values under a mask onpage 228 .

To edit the DEM, see Filtering and interpolatingDEM values on page 229 .

2. In the Select Layer dialog box, click Browse.3. In the File Selector dialog box, navigate to and

select the file.4. Click Open.

The file and its available layers are displayed in theSelect Layer dialog box.

5. Select a layer and click OK.

Creating a mask

A mask is a vector shape that identifies specific areasthat you want to edit. The mask does not change thevalues in the area that it covers.

1. From the DEM Editing dialog box, click the NewMask Layer button.

2. In the Maps tree, select the new bitmap layer.3. Use the New Shapes tools to draw a shape over

the area that you want to edit. For more information

about the New Shapes tools, see Adding points toan active layer on page 303 .

Replacing the elevation values under a mask

Once you have created a mask, you can replace theunsatisfactory value.

To replace values with a failed value

1. Create a mask.2. In the DEM Editing dialog box, click Fill.

To replace values with respective averages

1. Create a mask.2. In the Area Fills Under Mask area, choose

Average of Each Shape from the Fill using listbox.

3. Click Fill.

To replace a value with global average

1. Create a mask.2. In the Area Fills Under Mask area, choose

Average of All Shapes from the Fill using list box.3. Click Fill.

To replace a value with a specific value

1. Create a mask.2. In the Area Fills Under Mask area, choose

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Specified Value from the Fill using list box.3. Type a value in the Value box.4. Click Fill.

To remove a mask

1. In the DEM Editing dialog box, click the ClearMask button.

To hide a mask

1. In the Maps tree, disable the new bitmap layercheck box.

To save a mask

1. In the DEM Editing dialog box, click Save theMask.

Filtering and interpolating DEM values

You can use the filters available under Filtering andInterpolation to eliminate failed or incorrect values in aDEM. You can apply each filter repeatedly and indifferent combinations to achieve a cumulative effect.You can also limit the effect of the selected filter to aspecific area by creating a mask.

Remove Noise Filter

Noise refers to pixels containing distorted or failedvalues. Because pixels adjacent to failed pixels also tendto contain incorrect values, the Remove Noise Filter

uses two filters to identify failed pixel values and theirsurrounding pixels:

• The first filter calculates the average and varianceof the eight elevation values immediatelysurrounding each pixel, excluding failed andbackground pixels. If the center pixel is more thantwo standard deviations away from the average, it isreplaced with the failed value.

• The second filter counts the number of failed valuesimmediately surrounding each pixel. If five or morefailed pixels border the center pixel, the center pixelis also set to a failed value.

Erode holes

Because pixels adjacent to failed pixels also tend tocontain incorrect values, the Erode holes filter replacesthe eight pixels around each failed pixel with the failedvalue. When you apply the filter under a mask, the maskenlarges to cover any additional pixels replaced by thefailed value.

Median Filter

Ranks the pixel values within a 5x5 pixel frame accordingto brightness. The median is the middle value of thoseimage pixel values, which is then assigned to the pixel inthe center of the frame.

Smooth DEM

Is a Gaussian filter that calculates the weighted averageof all the pixels in a 3x3 pixel frame and assigns the valueto the center pixel in the frame. Failed and background

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pixel values are not replaced by the filter and are notused in the Gaussian calculation.

Interpolate

Replaces failed values with an estimate weighted bydistance calculated from the valid pixels surrounding thefailed pixel(s). The algorithm used to calculate theestimate is adequate for small areas of less than 200pixels, but is not recommended for larger areas.

To limit the filter to a specific area, you must create amask.

1. From the DEM Editing dialog box, choose a filterfrom the list box in the Filtering and Interpolationarea.

2. Enable one of the following options:3. Click Apply.

For more information, see Applying tool strategies forcommon situations in digital elevation models on page 230.

Applying tool strategies for commonsituations in digital elevation modelsEditing DEMs requires an understanding of the desiredresults. Each DEM presents a variety of problematicsituations. The following examples present the mostcommon problems and provide some methods to handlethem.

Adjusting pixel values for a lake

Because lakes have no features that can be used formatching during DEM extraction, lakes in a DEM oftencontain failed pixel values or incorrect elevation values.

1. Create a mask over the lake.2. Identify the elevation of the lake.3. In the DEM Editing dialog box, choose Specified

Value from the Fill using list box in the Area FillsUnder Mask area.

4. Type a value for the lake elevation in the Value box.5. Click Fill.6. Click the Clear Mask button.

Adjusting the pixel values for multiple lakes

1. Create a mask over each lake.2. In the DEM Editing dialog box, choose Interpolate

from the list box in the Filtering and Interpolationarea.

3. Enable the Use Mask option.4. Click Apply.5. In the Area Fills Under Mask area, choose

Average of Each Shape from the Fill using listbox.

6. Click Fill.7. Click the Clear Mask button.

Compensating for forests and urban areas

The repetitive textures of forests and urban areas oftencause those areas to contain a lot of failed values, noise,and poorly correlated elevation values.

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1. Create a mask over the area.2. In the DEM Editing dialog box, click Fill Mask from

Failed.3. Choose Interpolate from the list box in the Filtering

and Interpolation area.4. Enable the Use Mask option.5. Click Apply.6. Click the Clear Mask button.

Neutralizing cloud-covered areas

When clouds obscure a large area over rugged ormountainous terrain, the area may be too complex tointerpolate. To avoid confounding the data, you can setthe entire area to the background value.

1. Create a mask over the area.2. In the DEM Editing dialog box, choose Specified

Value from the Fill using list box in the Area FillsUnder Mask area.

3. Type the background value in the Value box.4. Click Fill.5. Click the Clear Mask button.

Removing noise from a DEM

Noise is a random occurrence of irrelevant ormiscorrelated values distributed throughout a DEM thatreduces its accuracy. The following procedure usuallyproduces a satisfactory DEM, except for areas containinglarge bodies of water, such as lakes.

1. Ensure all large bodies of water, such as lakes,have been fixed. See Adjusting pixel values for alake on page 230

2. In the DEM Editing dialog box, enable the Loadresults to input check box.

3. Choose Remove Noise Filter from the list box inthe Filtering and Interpolation area.

4. Enable the Entire DEM option.5. Click Apply.6. Click Apply again.7. Choose Interpolate from the list box in the Filtering

and Interpolation area.8. Enable the Entire DEM option.9. Click Apply.

10. Choose Smooth DEM from the list box in theFiltering and Interpolation area.

11. Enable the Entire DEM option12. Click Apply.13. Click Apply again.

Selecting the DEM layer

The Layer Selection dialog box lets you specify the DEMchannel you want to edit.

Browse:

Opens the File Selector dialog box.

Files:

Lists the files selected from the File Selector dialog box.

Channels/Segments available:

Lets you select channels and segments for editing.

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1. From the Layer Selection dialog box, clickBrowse.

2. In the File Selector dialog box, locate and select afile, and click Open.

3. In the Files pane, select a file.4. In the Channels/Segments available pane, choose

a DEM layer and click OK.

(See Editing a DEM on page 227 )

Viewing the scatter plot for a layer

Scatter plots are primarily used as data visualizationtools. Each plot shows the correlation between thehistograms for two channels.

Pixel distributions for the two specified image channelsdisplay in the scatter plot using one channel as the X-axisand the other as the Y-axis. They allow you to see wherethe majority of data values (or pixels) are concentrated.Frequency values at each point are color coded. Scatterplots also calculate relevant statistics and display at thebottom of the scatter plot.

Natural groupings of the spectral data are best illustratedwith a two-channel data set. For image data with morethan two channels, it is difficult to plot the values andvisually identify natural spectral groupings. Statisticaltechniques can be used to automatically group ann-dimensional set of observations into natural spectralclasses. This procedure is called cluster analysis.

A scatter plot can reduce the number of channels used

for a classification. If two channels have a very highcorrelation, you can omit one or the other as input for theclassification. You can also determine which portion ofthe spectra a given bitmap or training area occupies, andyou can use a scatter plot to determine the homogeneityof a bitmap or training area. If the scatter plot for thebitmap is tightly clustered with few outlying pixels, thespectral response for that area is homogenous in theselected image layers.

You can open the Scatter Plot dialog box from the Layermenu or from the training area collection window for asupervised classification.

Plot Scale

For 8 bit imagery, the scatter plot axis are 256 pixels by256 pixels. The top-left pixel represents the number ofpixels with a value of 255 for the input channel on theY-axis and zero for the input channel on the X-axis. Thebottom-right pixel represents the number of pixels with avalue of 255 for the input channel on the X-axis and zerofor the input channel on the Y-axis. When images areoutside the 0-255 range, the imagery is scaled to fit withinthat range. When images are outside the 0-255 range,the maximum digital number (DN) value is used for theplot scale.

Pixel Brightness

Is determined by the frequency of pixels in the image witha given gray-level value. Bright areas indicate commoncombinations and black areas indicate combinations thatrarely occur.

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1. From the Maps tree, select an image layer.2. From the Layer menu, click Scatter Plot.

Scatter plots typically show a bright smear in one area ofthe plot. By default, the plot appears with input channel 1on the X-axis and input channel 2 on the Y-axis.

In the controls area of the Scatter Plot dialog box, youcan specify the channels you want to show as the X andY axes. A color scheme for the plot and a look-up table(LUT) can be applied to either channel.

Changing the input channel for the X and Yaxes:

1. From the Scatter Plot dialog box, choose a channelfrom the X axis and Y axis list boxes.

The frequency is displayed using a simple grayscale or apseudo-color table.

Mask:

The Mask option allows you to create a scatter plot of aregion under a bitmap mask. You can also create ascatter plot of the entire raster. When creating a scatterplot of the entire raster, you set the Mask option to None.The Mask list box displays all of the bitmap layers thatare in the current area. The bitmap layers are listedwhether they are saved or not and for each savedbitmap, both the file and layer names are displayed.

Statistics:

The Statistics section displays the linear equation derivedfrom a linear regression calculation and the correlationcoefficient associated with the scatter plot. A value of'N/A' (Not Applicable) is given if these statistics cannot becalculated (usually if one of the selected channels isempty). The correlation coefficient measures thesimilarities of the two image channels. A value of oneindicates a complete correlation between two images,whereas a value of zero indicates there is no correlationbetween images. The A -1 value indicates a negativecorrelation.

Using the Scatter Plot dialog box

(For the Hyperspectral Scatter Plot only) Tospecify which values are compared

1. From the Hyperspectral Scatter Plot dialog box,enable one of the following options:

• Entire file: plots all the values in the twochannels

• Selected classes: plots only the values in theselected regions of the two channels (theMask list is disabled)

To change the color scheme of the display

1. From the Scatter Plot dialog box, enable one of thefollowing options:

• Gray: displays the plot with grayscalerepresentation

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• Pseudo: displays the plot with pseudo-colorrepresentation

Because the human eye can only detect approximately16 shades of grey, the scatter plot is more easilyinterpreted when displayed in pseudo-color with a whitebackground. You can apply an LUT to either inputchannel.

To apply an LUT to the X or Y-axis input channel

1. From the Scatter Plot dialog box, enable the ApplyLUT check boxes for the X- and Y-axis channels.

To hide the controls

1. From the Scatter Plot dialog box, click HideControls.

Zooming into and out of a scatter plot

You can zoom into an area of a scatter plot that isdisplayed in the Scatter Plot dialog box.

1. In the Scatter Plot dialog box, position the cursorover the area of the scatter plot you want to zoominto.

2. Right-click and select Zoom In or drag a rectangle.

You can click Zoom Out to revert to the previousview of the scatter plot and Zoom to Overview torevert to the original scatter plot.

Using the graph controls

Click Graph Controls at the bottom of the Profile Graphdialog box. You can also right-click in the profile andselect Graph Controls from the shortcut menu.

Use the Graphic Controls dialog box to

• Change the viewing range• Export the plot to a graphic file• Show and hide the plot legend.• Fix the plot aspect ratio• Change the plot background color• Print a plot

You can ensure the image information is not distorted byfixing the aspect ratio.

To open the Graph Controls dialog box

1. From the Scatter Plot dialog box, click GraphControls.

To fix the aspect ratio of a plot

1. From the Graph Controls dialog box, enable theFix aspect ratio check box.

To print a scatter plot

1. From the Graph Controls dialog box, click Print.

Changing the x and y view ranges

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You can control the range and hold the X and Y axes tothe original relationship.

1. In the X View Range and Y View Range areas,enter a value in the Min and Max spin boxes.

The default range of values for 8-bit imagery is 0 to255.

The range varies depending on the ground distancecovered by an image and the length of a vector.

Exporting a profile

You can change the file format before selecting an outputfile.

1. In the Graph Controls dialog box, choose a fileformat from the Format list box.

2. Click File.3. In the File Selector dialog box, enter a file name in

the File name list box.4. Click Save.5. In the Graph Controls dialog box, click Export.

Working with legend and color controls

To show a legend for the color scale

• From the Graph Controls dialog box, enable theShow legend check box.

To change the background color for a scatterplot

• From the Graph Controls dialog box, choose acolor from the Background palette.

Interpreting a profile table

In the case of an RGB layer, a Profile Table is anumerical representation of the RGB input channels of anactive image.

Sample Points and Distances

The table lists numeric information for each sample pointalong the current profile. A sample point is a pixel. Thespacing is determined by the pixel size. The rangedepends on the length of the vector and the image scale.A field is displayed for each of the channels that ismarked Visible in the Profile Options area.

1. From the Profile Table dialog box, click Options.

Profile Options:

Gives you control over various aspects of the profilegraph and table. You can control the following properties:

Color:

Displays the color used to represent each channel on theprofile graph. You can change any color by clicking onthe color chip you want to change. This opens the Line

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Color editor based on the RGB color space. The colorrepresentation of the channel's profile on the graph ischanged.

Visible:

A check mark in this field indicates that a particularchannel is visible in the profile graph and profile table.

Current Channel:

Indicates which plotted channel is associated with themensuration bars. There can be only one currentchannel, which is indicated by an X. To select the currentchannel, click the appropriate field under the CurrentChannel column.

Profile View:

Sets the coordinates for the horizontal axis of the ProfileGraph. The sample point coordinates are based on theimage pixel size, in meters. Choose betweenGeoreferenced and Sample Point coordinates. IfGeoreferenced is selected, the values in the X axis aredisplayed in metres. If Sample Points are selected, thevalues in the X axis represent pixel units. For example, ifa vector line is 8000 m long, the maximum value for the Xaxis if georeferenced is selected in the Profile options is8000. If the imagery has a resolution of 30 m, themaximum value for the same line displayed using Samplepoints is approximately 267 (8000/30).

Changing the color of a channel

Color spaces have been developed as a means ofdescribing color. Two of the most common color spacesare RGB (Red-Green-Blue) and CMY(Cyan-Magenta-Yellow). The former is used by monitorsand the latter is usually used by printers. RGB and CMYcan be difficult to understand.

Another color space, IHS (Intensity-Hue-Saturation) givea more accurate representation of how the eye interpretscolor. IHS transformations are useful in digital imageprocessing, as they allow for greater control over thecomponents that make up color.

You can change the color of any channel by clicking onits color chip. This opens the Line Color editor. The colorrepresentation of a channel#s profile on the graph ischanged.

1. Click the color chip for the corresponding channel.2. In the Line Color editor, move the Red, Green, or

Blue slide controls to the left or right to adjust yourcolors.

3. Click Close.

To customize the color of the profile vector, use the SetLine Color tool on the Display toolbar.

Changing the profile vector color

1. Click a line.2. On the Display toolbar, click the Set Line Color

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arrow and choose a color from the color palette.

(See About the Change Color dialog box on page 237 )

About the Change Color dialog boxThe Change Color dialog box allows you to create acustom color using one or a combination of the followingpalettes:

Basic Colors:

Is a palette of basic colors that are preset and cannot bemodified.

Color Continuum:

Is a palette composed of all possible hue/saturationcombined values.

Intensity/Lightness Scale:

Controls the brightness of the color. It is the only paletteavailable if the chosen color model is Gray.

The color you create using the palettes is visuallydisplayed alongside the color that is being replaced.These are referred to as the New and Old colors,respectively.

The numeric representation of the new color opens in aseries of data entry fields. You can edit the entries inthese fields and the new color changes accordingly. Thenumber of fields present corresponds to the chosen color

model.

RGB:

Is one of the additive color models and is based on thelight being emitted from computer monitors. The threeprimary colors are red, green, and blue. Combining thered, green, and blue colors in various proportionsproduces all the colors on your screen.

CMYK:

Is one of the subtractive color models and is based onthe amount of light being absorbed and reflected by anink film. This model is often used in printing. The primarycolors are cyan, magenta, yellow, and black.

HLS/HIS:

Is a more intuitive model based upon the way weperceive color. The primary components are hue (shadeof color), lightness/intensity (brightness of color), andsaturation (strength or purity of color).

Gray:

Is a continuum of gray values ranging from pure black topure white.

Printing without the mensuration barsshowing

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You can print the profile graph by clicking Print at thebottom of the Graph Controls dialog box.

1. Open the Profile Table dialog box.2. Click Options.3. In the Profile Options dialog box, click Close.4. In the Graph Controls dialog box, click Print.

Using the profile statisticsYou can open the Profile Statistics dialog box by clickingthe Statistics button in the Profile Table dialog box.

Statistics are shown for each RGB channel in theselected layer. The dialog box calculates the minimum,maximum, average, weighted average, and weightedaverage summary statistics for the sample gray valuesalong the profile.

Weighted average is the most accurate measure ofcentral tendency among sample points. The weight of asample gray value is the ratio of the length of a sampleinterval over the total distance of all the sample intervals.

Controlling the cursorYou can use the Cursor Control dialog box to specify ordetermine the location of the cursor in the view pane. Toopen the Cursor Control dialog box, click the CursorControl button on the Tools toolbar. The cursor controlinformation shows both the location on the map page andto the georeferenced ground location represented in theimage.

The Cursor Control dialog box has four areas that displaythe cursor position in different coordinate systems. Youcan move the cursor in any of the supported coordinateschemes by changing the any of the coordinates.

The Paper area measures the paper size set for the Map.It can be larger than the area view where imagery isdisplayed. The paper size can be changed in the Mapstree by right-clicking the Map layer and choosingProperties. From the Map Properties dialog box, chooseProperties and then click the Page Setup tab. The cursorcontrol panel shows the location in millimetres with theorigin at the bottom right of the map.

If more than one file is opened in the view pane, thecoordinates are based on the selected database. Youcan change the database file. The result is the pixel andline that the cursor points to in the currently selecteddatabase. The file origin, (0,0) is the top left of the imageor file. If the projection has not been set for a file, thedatabase coordinates are not displayed.

The Geocoded area displays the cursor coordinates ingeocoded coordinates (for example, Eastings andNorthings) according to the geocoding shown in theCursor Control dialog box. If opened data has noassociated geocoded locations, the geocoded location isshown in pixels and lines. The units displayed indicatethe geocoding type.

The User Defined Projection area shows Lat/Longcoordinates as the default if sufficient geocodinginformation is available for the viewed data. Typically,UTM data with a valid zone number must be provided for

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this transformation to occur. If a projection has not beenset, the User Defined Projection coordinates are notdisplayed.

Opening the GPS tool

The GPS Tool provides two functions: you can use it toupdate the position of the cursor within an Area layer andas a data input device for a new vector layer. In eithercase, you must have an Area layer that contains theappropriate georeferencing information open.

Before the GPS Tool can be opened, the GPSReceiver/Focus connection must be set. The GPSreceiver connection is made through the Focus Optionsdialog box. (See Setting up a GPS receiver on page 111 )

1. Ensure a GPS receiver is connected to the systemaccording to manufacturer specifications and that itis set up correctly.

2. From the Tools menu, click GPS Tool.

Using the GPS tool

1. Ensure a GPS connection has been established.2. Open an Area layer containing appropriate

georeferencing information.

The georeferencing bounds should correspond tothe area where the GPS receiver is located. If theGPS receiver is outside of these bounds, youcannot update the cursor or collect vectors.

3. From the Tools menu, click GPS Tool.

When the GPS Tool is active, you can use it to updatethe cursor position or to add vector data to an Area in theproject.

Updating the cursor position using the GPSreceiver

1. Ensure the GPS Tool is open.2. From the GPS Tool dialog box, click one of the

following buttons:• Capture Stream: automatically updates the

cursor position at the specified stream interval.For more on stream interval. (See Setting up aGPS receiver on page 111 )

• If you want to stop the stream capture, clickFinish.

• Capture Point: moves the cursor only once.To reset the cursor position using the GPSReceiver, click the button again.

Inputting vector point data using the GPSreceiver

1. Ensure the GPS connection has been established.2. In the Maps tree, right-click an Area layer and click

New Vector Layer.3. In the New Vector Layer dialog box, enable the

Point option.4. Click OK.5. In the Maps tree, select New Point Layer.6. On the Editing toolbar, click the New Shapes arrow

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list and click Points.7. In the GPS Tool dialog box, click one of the

following buttons:• Capture Stream: adds new points to your

vector layer at the specified stream interval.• If you want to stop the point capture, click

Finish.• Capture Point: adds a new point to your

vector layer. You can continue to collect pointsby repeatedly clicking the button.

Inputting vector line or polygon data usingthe GPS receiver

1. Ensure the GPS Tool is open.2. In the Maps tree, right-click an Area layer and click

New Vector Layer.3. In the New Vector Layer dialog box, enable one of

the following options in the Layer Type area:• Line• Topological Line• Polygon• Topological Polygon

4. Click OK.5. In the Maps tree, select the new layer.6. In the GPS Tool dialog box, click one of the

following buttons:• Capture Stream: adds a new vertex to the

vector layer at the specified stream interval.New vertices are added to the line or polygonuntil you click Finish.

• Capture Point: adds only the initial vertex tothe line or polygon layer. You can continue tocollect vertices for the line or polygon by

repeatedly clicking the button.

Using the ADAPT algorithm

You can use a single channel with a pseudo-color table(PCT) to represent data instead of a full three-channelRGB image. This helps if you need to import data tosoftware that accepts only single-channel .tif files withPCTs. It can also be used to reduce an RGB file to a thirdof its original size. You can also change data from asingle-image channel with a PCT to full RGBrepresentation.

When preparing color images for export to third-partysoftware (for example, a GIS system with limited colorcapability), the RGB2PCT compresses a 24-bit color(RGB) image into a single 8-bit layer based on a PCT. APCT colors the compressed image to look similar to theoriginal 24-bit color image.

The input file (FILE) contains the input RGB layers(DBIC) and the target layer where the compressed result(DBOC) is saved. When enhancing image data with anLUT, it should first be applied to the RGB layers using theLUT PACE program.

The input RGB layers and the output-compressed layershould be 8-bit. This restriction is due to the 8-bit natureof a PCT. While any type of image layer can be used,values are internally converted to 8-bit data. Using non8-bit data may result in unexpected results.

1. Open and run the ADAPT program from theAlgorithm Library to generate a well-distributed PCTto represent a particular image.

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2. Choose RGB2PCT from the Algorithm Library.3. Select three raster layers you want to use as your

RGB channels.4. Select the PCT that was created using ADAPT.5. Run RGB2PCT and save the results in the Maps

tree.

Also see PCTMAKE, CMPRSS8, and ERRDIFF in theAlgorithm Library.

Converting RGB to pseudo-color

1. From the Algorithm Library, run the algorithmADAPT.

ADAPT takes a 24-bit RGB image and compressesit to a single 8-bit image, based on a user-suppliedPCT. For each pixel, the nearest color in thesupplied PCT is established and a correspondingcolor index is placed in the output channel.

The results from ADAPT are used as input into theRGB2PCT program. RGB2PCT takes a 24-bit RGBimage and compresses it to a single 8-bit image, basedon a user-supplied PCT. For each pixel, the nearest colorin the supplied PCT is established, and a correspondingcolor index is placed in the output channel.

Converting RGB to pseudo-color

• From the Algorithm Library, run the PCE algorithm.

PCE encodes an input channel into three outputchannels (such as red, green, and bluecomponents) using a PCT held in a databasesegment.

Opening the PCT Editing dialog box

You can create and modify PCTs in the PCT Editingdialog box. A pseudo-color layer appears in the Mapstree as an icon with vertical color bars followed by layerfile information. A PCT is generated only for an imagelayer that is designated as a PCT layer.

• From the Maps tree, right-click a pseudo-color layerand click Edit PCT.

Adjusting the pseudo-color for single values

1. From the PCT Editing dialog box, click the SingleValue tab.

2. Click one of the following buttons:• Smooth: creates a smooth color ramp from

dark blue to magenta• Stepped: creates a series of short color ramps• Random: creates a set of random colors• Gray Ramp: creates a gray ramp with a black

value of 0 and a white value of 255

Editing a value

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The Current Pseudo-Color Table displays color values forthe current PCT. You can edit the breakpoint and RGBvalues in the table cells.

1. In the PCT Editing dialog box, double-click the cellyou want to change and type a new value.

If you want to select multiple PCT entries, drag overa series of list entries.

Selecting a basic color value

Color Selection lets you modify the output color of thecurrent PCT using the controls in the Color Selectionarea. The following is a list of the controls in the colorselection area:

• Basic color sample table• Basic color sample bar• Color selection control• Color Model list• Old and New sample boxes• Red, Green, and Blue boxes• Gray Value box• Apply command

1. Select a color model from the Model box.2. Click a tile in the Basic Colors table.

The color range changes in the Color Continuumand Intensity controls.

3. If required, use the Color Continuum, Instensity,or color value boxes to adjust the selected color.

4. Click Apply.

Customizing range-basedpseudo-color tables

You can edit PCT channels for range-basedpseudo-color. Standard and custom color selections areavailable under the Range-based tab. You can maintainexisting PCT colors or replace them with predefinedstandard PCT color values.

1. From the PCT Editing dialog box, click theRange-based tab.

Using standard mode

1. From the PCT Editing dialog box, click theRange-based tab.

2. Enable the Standard option in the Color Selectionarea.

Keeping the original color values

You can maintain or revert to the original pseudo colorvalues.

1. Click Use Original PCT.

Selecting colors within the range

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1. From the Range-based page, enable the Customoption in the Color Selection area.

2. Drag the left and right markers to the positions youwant on the color bar in the Color Selection area.

Applying pseudo colors to pixel values in araster

You can render pseudo RGB color values to the pixelvalues of the active raster. This allows you to distinctlyview specific areas of the raster.

1. In the Maps tree, right-click the pseudo-color layerand select Edit PCT.

The PCT Editing window appears.

2. Click the Range-based tab.3. In the Color Selection area, click Custom.4. Double-click First Color.

The Select First Color in Range window appears.

5. Select a color from which you want the color rangeto start.

6. Click OK.7. Double-click Last Color.8. The Select Last Color in Range window appears.9. Select a color at which you want the color range to

end.10. Click OK.11. Click Interpolate.

The color bar below First Color and Last Colordisplays the new color range.

12. In the Histogram area, slide the markers or specifythe values in the Min X and Max X boxes to definethe section to which you want to apply the colorrange.

13. If required, go back to the color bar and slide itsmarkers to narrow or widen the color range. Youcan also specify the values of the range in the LeftMarker and Right Marker boxes.

The color tabs of the histogram left and rightmarkers change color accordingly.

14. Click one of the following options from the ValuesOutside Range list in the Setup Preview of NewPCT section:

• Set to Black, which blackens the area of thehistogram that is outside the specified range

• Set to White, which whitens the area of thehistogram that is outside the specified range

• Ignore, which retains the original color of thehistogram outside the specified range

15. Click Compress.

The histogram reflects the new color range. Thecolor bar below Compress changes to reflect thenew color range and the option specified in theValues Outside Range list. The specified pseudocolor range is rendered to the specified pixel valuesof the active raster.

Opening the Raster Editing dialog box

You can replace the pixel values in an image with a valueof your choice. After you have set a value in the RasterEditing dialog box, you can use the New Shapes tool to

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edit the raster (see Adding points to an active layer onpage 303 ).

1. On the Editing toolbar, click the Raster Editingtool.

Specifying a value

1. In the Pixel value box, type the value that you wantto use.

2. In the Pixel value box, type the value that you wantto use.

If you want to replace all the pixel values within thepolygon instead of just drawing the outline of thepolygon, select the Fill polygon check box.

3. In the Line width box, type a value that representsthe thickness of the line in pixels. Click OK.

Changing a default enhancement

Images can be processed at several levels, fromstandard enhancements that filter images with a singlemouse click to fully customized enhancements usingLUTs and histograms. Original image files can be difficultto visually understand. Enhancements make imageryclear and easier to interpret. When you open an imagefile in Focus, it is automatically enhanced in the viewpane. You can change the default enhancement. (SeeSetting options and preferences on page 101 )

Changing Default Enhancements

You can remove the default enhancement from theRaster toolbar by clicking the Enhancements arrow andchoosing None. The enhancement is removed, and theview pane shows the image with no enhancement. Youcan also change the enhancement that is automaticallyapplied to imagery when you open new files.

1. From the Tools menu, click Options.2. In the Options dialog box, select Layers.3. In the Rasters area, choose a default enhancement

from the Default visual enhancement list box.4. Click OK.

There are three methods for enhancing images withFocus. For quick adjustments to your image data, youcan use the Raster toolbar command buttons or theshortcut menu in the Focus Maps tree. For more detailedcustom enhancements you can use the LUT Editor. Theimage enhancement is only applied through your systemmemory and must be saved if you want to use aparticular LUT again or if you want to export theenhanced image.

Applying a linear enhancement

There are several commands on the Raster toolbar forenhancing and adjusting the appearance of your imagesquickly. The Raster toolbar includes contrast andbrightness controls along with a list of standardenhancements, such as Linear, Root, Adaptive,Equalization, and Infrequency. The followingenhancements are available from the Raster toolbar:

None

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Removes all enhancements and displays the originaluncorrected image.

Linear

Improves the overall contrast of an image by stretchingthe minimum and maximum values in the image uniformlyover the entire available dynamic range. Thisenhancement is best applied to images that have anormal distribution of digital number (DN) values.

Root

Applies a square root enhancement, which compresseshigher DN values in an image and disproportionatelyexpands the darker values. Original darker values in theimage are given more contrast than the original bright(high-DN) values.

Adaptive

Applies an optimal enhancement curve, which is anadaptive derivative of an image histogram.

Equalization

Applies a histogram equalization enhancement.

Infrequency

Applies an infrequency enhancement, which maps graylevels based on frequency of occurrence.

The Linear stretch enhancement improves the overall

contrast of an image by stretching the minimum andmaximum values in the image over the entire availabledynamic range.

1. On the Raster toolbar, click the Enhancementsarrow and choose Linear.

Zooming an image feature with anenhancement

1. In the view pane, click on or near the feature youwant to zoom.

2. On the Zoom toolbar, click the Zoom 1:1 ImageResolution button.

Note: When an image overview is set in the view pane,all image statistics are used to calculate theenhancement. When an image is zoomed, apply theenhancement again. Focus uses the statistics of thezoomed image to calculate the new enhancement.

Image Enhancements and Image Statistics:

Digital numbers in images from the same sensor can varybecause of land cover or environmental changes in thescene. Enhancements are based on statistics from eachimage. Therefore, the effects of an enhancement canvary in different images taken from the same sensor.

For example, RADARSAT images are stored in 16-bitunsigned channels supporting a dynamic range from zeroto 65,535 digital numbers. The usable image values inthe radarsat.pix file are zero to 30,000 digital numbers.The image appears dark, with no enhancement, because

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it uses less than half of the available range.

When Focus collects statistics for applying anenhancement, the Tail Trim option omits the upper andlower 2% of the image histogram.

Adjusting toolbar enhancements

You can control how Focus computes each of thestandard enhancements before they are applied to animage by adjusting the tail trim options from the Rastertoolbar.

Applying the Tail Trim option

The pixel values for the image are averaged out over thedynamic range but the first 2% and the last 2% of valuesare omitted from the enhancement computation. You canalso adjust the amount of tail trim from the enhancementscommand list from 1% to 5%.

• On the Raster toolbar, click the Enhancementsarrow and click Tail Trim.

A check mark next to Tail Trim indicates the optionhas been enabled.

Adjusting the amount of Tail Trim

1. On the Raster toolbar, click the Enhancementsarrow and click Set Trim%.

2. Choose a number that represents the percentage oftail trim.

The enhancement must be re-applied to the newview pane.

Exclude Min/Max

If this option is enabled, the minimum and maximumvalues are not used as end points when applying theenhancement.

The table below shows a simple pix file with only 7 pixelsand 1 line. When the Exclude Min/Max option is enabled,the lowest and highest digital number (DN) values(excluding the outliers 0 and 255) are stretched to 0 and255. When the Exclude Min/Max option is disabled, theoriginal minimum and maximum values are used asanchors. The remaining values are stretched with respectto this range.

Table 10.

Pixel # ofline 1

1 2 3 4 5 6 7

Raw DataDN

0 5 50 51 52 60 255

EnhancedDN ExcludeMin/Max

0 0 127 140 153 255 255

EnhancedDN IncludeMin/Max

0 170 212 216 221 255 255

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Decreasing the image contrast

Interpreting image data is often simplified by adjusting theimage contrast and brightness. You can increase ordecrease the image contrast and brightness with theRaster toolbar controls. To increase the image contrast,click the Contrast button on the Raster toolbar.

1. On the Raster toolbar, click the Contrasts arrowand choose Decrease.

You can see an approximate 10% change in the imagecontrast each time you click the Contrast button. You canalso return the contrast level to the original enhancementbefore the contrast was changed by choosing the Resetoption.

The Brightness tool lets you increase, decrease, or resetthe image brightness. To increase the image brightness,click the Brightness button on the Raster toolbar. Eachclick changes the image brightness by approximately10%.

Decreasing the image brightness

1. On the Raster toolbar, click the Brightness arrowand choose Decrease.

You can also choose Reset to return to the originalthe brightness level.

Enhancing images from the shortcut menu

You can also apply image enhancements with theshortcut menu in the Maps tree. The same imageenhancement commands in the Raster Toolbar are foundin the shortcut menu.

1. In the Maps tree, right-click a data file layer andclick Enhance.

2. Choose an enhancement.

Opening the LUT editor

Focus allows you to create custom enhancements of8-bit, 16-bit, and 32-bit rasters.

Using the LUT Editor, you can create enhancements bydirectly tracing or editing the histogram of the activeraster. You can also compare the same histogram usingdifferent enhancements, and change the minimum andmaximum values within the bit depth and x-axis ranges.

1. In the Maps tree, right-click the active layer.2. Select Enhance and then select Edit LUTs.

The Multi Histogram Display window appears if anRGB map layer is selected, otherwise, theHistogram Display window appears.

3. Click a histogram.

The LUT Editor appears. The Min X and Max Xvalues mark the boundaries of the graph along thex-axis. These values change accordingly when youmanually change them or slide the x-axis level

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markers. The Min LUT (X) and Max LUT (X) valuesencompass the range that marks the bit depth of theimage. These values can change when youmanually change them or slide the y-axis levelmarkers.

Displaying a histogram in the LUT Editor

Focus allows you to display the input and output versionsof the histogram that you want to edit in the LUT Editor.You can also display the breakpoints that can be used toedit the histogram. The changes made to the breakpointsare reflected in the ouput.

1. In the LUT Editor, select one of the followingoptions from the Mask list box:

• Entire raster: displays a histogram of the entireraster.

• Current view area: displays a histogram of thearea that is displayed in the Focus viewer.

• Bitmap layer: displays a histogram of a regionunder a bitmap mask. The bitmaps are listedwhether they are saved or not. Both the fileand layer names are displayed for the savedbitmaps.

2. From the View menu, select or cancel the selectionof the following options:

• Input Histogram: displays the original versionof the histogram.

• Output Histogram: displays the resultinghistogram after enhancements

• Breakpoints: displays nodes, which facilitatethe enhancement process

Moving an entire histogram

You can move the entire histogram to the right or left ofthe x-axis boundaries to change the range.

• In the graph area, right-click and drag the entiregraph to the left or to the right.

Using the LUT tools

You can undo edits and compare different versions of ahistogram for the same image data using the tools on theLUT Editor.

When the LUT Editor is opened, Focus stores a copy ofthe histogram as a smaller version and displays it to theright of the LUT editor in the preview window. When youmake changes, you can switch between the previous andthe edited LUT using the Toggle option. You can alsocopy the edited LUT and save it as a temporary backup.

Using the LUT enhancement options

Enhancements are applied to values within the boundsdefined by the x-axis and y-axis markers.

The vertical markers set the minimum and maximumoutput grayscale values. The horizontal markers set therange of input grayscale values for an enhancement.

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To allow tail trimming, enable the Tail Trim check box. Inthe Tail Trimming list box, select the tail trim percent from1 to 5. You can also enable the Exclude Min./Max checkbox and enter values in the appropriate boxes. Once youapply an enhancement, you can customize it.

The view with the changes in the histogram panel isautomatically updated.

Trace-editing a LUT histogram

You can use the LUT Editor to create customenhancements by directly editing the red histogram in theLUT graph. You can trace the general contours of ahistogram. Focus redraws the image in the view pane.

1. In the LUT Editor, click the Manual Mode button inthe Graph editing tools area.

2. In the graph area, drag a contour.

Comparing custom enhancements

You can create different custom enhancements andswitch between the preview window and the LUT Editorusing the Copy and Toggle options on the LUT Editor.

1. In the LUT Editor, click the Manual Mode button inthe Graph editing tools area.

2. Create a custom enhancement by trace-editing thehistogram.

3. Click Copy.4. Create a new trace-edit enhancement or click on

one of the enhancements to the right of the maingraph.

5. Click Toggle.

You can also edit the LUT directly in a spreadsheet-styledialog box by selecting Edit Table from the Graph editingtools. To open the LUT for a histogram, click Edit Table inthe Graph editing tools area.

Some of the other graph editing tools include: AddBreakpoint, Move Breakpoint, and Delete Breakpoint.These options let you edit the LUT for a specific locationon the original image histogram. To show the breakpointson the curve from the view option list, chooseBreakpoints. The Thin Breakpoints option removesexcess breakpoints along straight stretches that areassociated with a LUT.

Applying a new look-up table to thecorresponding image plane

In the LUT, you can view both breakpoints and look-upvalues.

1. In the Graph editing tools area, click the EditTable button.

2. In the Lookup Table dialog box, enable the ViewLookup Values check box.

3. View the breakpoints in the Breakpoints table.

The values for X and Y where Y = LUT (X). Thevalue of Y is a function of the value of X in terms ofboth the position of X in the LUT graph and in termsof the mathematical function that is currentlyapplied.

4. In the LUT Editor, click Close.

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Working with spatial filtersCoherent signal scattering in SAR data often causesimage speckles or salt and pepper effects. Speckling isinherent in most images and can inhibit accurate imageinterpretation. There are several image filters in Focus tohelp manage image speckling.

Filters can enhance or subdue the details of an image.They can also be adjusted to sharpen, smooth, or detecthidden edges that are present in an image but notimmediately visible. You can use the low-pass andhigh-pass filters to reduce graininess and highlight edgedetails in images. There are also specialized filters thatyou can use to reduce sensor noise and to clean up radarimagery.

Filter computations are based on pixel samples drawnfrom a moving sample set, referred to as the kernel. TheKernel samples the image pixels and applies the filter tothe center pixel in the sample. Once the filter is applied tothe first sample, the kernel moves one pixel to the rightand re-applies the filter until the entire image has beensampled. The kernel dimensions, measured in pixels,must always be an odd number; for example, 3x3 or11x15. When the entire image has been sampled, Focusapplies the changes to the entire image in the view pane.

(See Opening the Filter dialog box on page 250 )

Opening the Filter dialog box

The Filter dialog box lets you apply high-pass, low-pass,

and custom filters. You can control the X and Ydimensions of the kernel in the Filter Size boxes. You canwork with different filter types.

1. Select an image layer in the Maps tree.2. From the Layer menu, click Filter.

Filtering under a mask:

You can apply the filters to all the data in the layer or youcan create a bitmap mask to restrict the filtering processto a particular area in the layer. See Filtering under amask on page 251 .

Low Pass Tab:

Low-pass filters pass only the low-frequency informationor the gradual gray-level changes. They produce imagesthat appear smooth or blurred when compared to theoriginal data. Click the Low Pass tab to work withlow-pass filters. See Using low-pass filters on page 251 .

Speckle Filters:

Also called adaptive filters, speckle filters are used withradar imagery to provide low-pass filtering. Speckle filtersremove radar noise while maintaining high-passinformation, such as edges. You can work with specklefilters under the Low Pass tab. (See Using low-passfilters on page 251 )

High Pass Tab:

Pass only the high-frequency information or the abrupt

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gray-level changes. The high-frequency image containsall of the local details of the image, such as object edges.Click the High Pass tab to work with high-pass filters.(See Using high-pass filters on page 254 )

Custom Tab:

Lets you design your own filter. You can specify thecoefficients for a filter template, regardless of the actualcoefficients. Custom filters perform spatial filtering oneach pixel in an image using the gray-level values ineither a square or a rectangular kernel. You createcustom filters under the Custom tab.

(See Creating custom filters on page 256 )

Filtering under a mask

You can create a bitmap mask to restrict the filteringprocess to a particular area in the layer.

1. In the Maps tree, create a bitmap layer. SeeCreating a new bitmap layer on page 141 .

2. On the bitmap layer, use the New Shapes tool setto draw shapes over the areas that you want tofilter. See Adding points to an active layer on page 303.

3. From the main menu, click Layer and then clickFilter.

For more information, refer to Opening the Filterdialog box on page 250 .

4. From the Mask list box in the Filter dialog box,select the bitmap layer that contains the mask.

The Mask list box displays all of the bitmap layersthat are in the current area. The bitmap layers arelisted whether they are saved or not. For eachsaved bitmap, both the file and layer names aredisplayed.

5. If you want to display or save the results for themask area only, enable the Output only mask areacheck box.

The data that is not covered by the mask is set tothe No Data value and is not saved in the outputfile.

Using low-pass filters

Low-pass filters pass only the low-frequency informationor the gradual gray-level changes. They produce imagesthat appear smooth or blurred when compared to theoriginal data. For non-radar image data, the followinglow-pass filters are available:

Average Filter

smooths the image data to eliminate noise. A 3x3 filterkernel computes the sum of all pixels in the filter kerneland divides the sum by the total number of pixels in thekernel.

Median Filter

also smooths your image data, but computes the medianvalues within a rectangular filter window surroundingeach pixel. This has the effect of smoothing the image

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and preserving edges.

In a 3x3 kernel, the median filter finds the median pixelvalue, the middle value in an ordered set, where an equalnumber of values are below and above the median. Forexample, 8 is the median value for the following 3x3kernel in a gray-level values set:

Mode Filter

computes the mode of the gray-level values that occurmost frequently in the filter kernel. For example, in a 3x3filter window with the following pixel values, the filteredpixel value of 3 occurs five times.

The mode filter is calculated as follows:

Mode filters are typically used to clean up thematic mapsfor presentation purposes. This filter replaces small islandthemes with their larger surrounding themes. With themode filter, the maximum kernel size is 7x7. The filterwindow can be rectangular.

Sometimes, two values can be equally distributed withinthe kernel sample. In such cases, if the center value isone of the competing values, it becomes the kernelsample value. If not, the first instance of the competingvalues becomes the sample value.

For example, in a 3x3 filter window with the followingpixel values, the pixel values 3 and 5 each occur three

times. In this case the Mode pixel of the filter kernel iscalculated as follows:

Neither 3 nor 5 is at the center of the kernel. The 5 in thetop row is encountered first and therefore becomes themode value.

1. In the Filter dialog box, enter an X- and Y-filterkernel size in the Filter size spin boxes.

The larger the kernel size, the smoother (moreblurred) the image.

2. Click the Low Pass tab.3. Enable one of the following filter options:

• Average• Median• Mode

4. Click Apply to View.

The filter is applied to the image in the view paneonly.

If you want to adjust a filter or change to a differentone, click Remove View Filter.

Note: Image filters are not cumulative. Each filter isapplied to the original data stored in the image file.

Using Gamma filters:

Most image files contain some type of high-frequency

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noise (speckling). While a low-pass filter reduces imagespeckles, it can also degrade some of the finer detail inthe image. Special low-pass filters, called Gamma filters,can preserve image details by filtering on individual pixelsin an image using the gray-level values in a squarewindow surrounding each pixel. You can apply a specklefilter to preserve some of the linear features in the image.Gamma filtering is primarily used on radar data to removehigh-frequency speckle, while preserving high-frequencyfeatures (edges). The input for the number of looks of theradar image is used to calculate the noise variance. Youcan specify an intensity or amplitude formate for the radarimage.

The dimensions of a Gamma filter must beodd-numbered and can be from 3x3 to 11x11 pixels.Filter size greatly affects the quality of processed images.If a filter is too small, the noise filtering algorithm is noteffective; if a filter is too large, subtle details of the imagewill be lost in the filtering process. A 7x7 filter usuallygives the best result.

All pixels are filtered. In order to filter pixels located nearedges of an image, edge pixels are replicated to givesufficient data.

For example:

Table 11.

a1 a2 a3 a4 a5 a6 a7 a8 a9

In a 3x3 filter window

Algorithm:

The resulting gray-level value R for the smoothed pixel is:

R = I for Ci less than or equal to CuR = (B*I +SQRT(D))/(2*ALFA) for Cu < Ci < CmaxR = CP for Cigreater than or equal to Cmax

where:

NLOOK = number of looksVAR = variance in filterwindowCP = center pixel gray-level valueI = meangray-level in the filter windowCu = 1/SQRT(NLOOK)Ci =SQRT(VAR)/ICmax = SQRT(2)*CuALFA = (1 +Cu**2)/(Ci**2 - Cu**2)B = ALFA - NLOOK - 1D = I*I*B*B+ 4*ALFA*NLOOK*I*CP

For the amplitude image, each gray level will be squaredbefore applying the algorithm, and the square root of thecalculated pixel is returned as the final result.

Applying a gamma filter

1. In the Filter dialog box, enter an X- and Y-filterkernel size in the Filter size spin boxes.

Use the mode-value information for an image to setup a Gamma filter.

2. Click the Low Pass tab.3. Enable the Gamma filter option.

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4. In the Number of Looks box, enter a value thatrepresents the number of noise-variationcalculations of the radar image that you want to use.

5. In the Image Format list box, choose one of thefollowing:

• Amplitude• Power• DB

6. Click Apply to View.

If the filtered image is hard to see at your currentresolution, you can zoom the image to see the filtereffects. The Gamma filter suppresses the imagespeckles, while the linear details are preserved.

Note: You must enter correct image mode values for theimage data files you are working with. The number oflooks and the image amplitude information is available inthe format definition included with your data.

(See Using high-pass filters on page 254 andSaving afiltered image to a new file on page 257 )

Using high-pass filters

High-pass filters emphasize border pixels betweencontrasting areas and are often referred to as edgedetectors. Like speckle filters, they highlight pixelcontrasts associated with linear features and edgedetails. You can apply a high-pass filter to highlight pixelcontrasts associated with linear features and edgedetails.

Gaussian Filter (SIGMSQ = 4)

is used as a band-pass filter to blur an image. This filteruses the following Gaussian function to compute the filterweights:

G (i, j) = exp ( -((i-u)**2 + (j-v)**2) / (2 * SIGSMQ) )

where (i, j) is a pixel within the filter window, (u, v) is thecenter for the filter window, and SIGMSQ is set to 4.

The filter weights W(i, j) are the normalized values of G(i,j) over the entire filter window; therefore, the sum of allweights is 1.

The gray level of a filtered pixel is the sum of W(i, j) *V(i,j) over all pixels in the filter window, where V(i, j) is theoriginal value at location (i, j).

Note: In order to filter pixels located near the edges ofthe image, edge pixel values are replicated to givesufficient data.

Laplacian Edge Detector Filters

generate sharp edge definition of an image. These filterscan be used to highlight edges that have both positiveand negative brightness slopes.

The two Laplacian filters have different weightarrangements, as shown below:

Table 12.

Type 1 Type 2

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0 1 0 1 -4 1 0 1 0 -1 -1 -1 -1 8 -1 -1 -1 -1

where the sum of all weights = 0

Example of 3x3 Laplacian filters

Note: In order to filter pixels located near the edges ofthe image, edge pixel values are replicated to givesufficient data.

Sobel Edge Detector Filter

creates an image where edges (sharp changes ingray-level values) are shown. Only a 3x3 filter size canbe used with this filter.

This filter uses two 3x3 templates to calculate the Sobelgradient as shown below:

Table 13.

-1 0 1 -2 0 2 -1 0 1 1 2 1 0 0 0 -1 -2 -1

X Y

Templates

Table 14.

a1 a2 a3 a4 a5 a6 a7 a8a9 3x3 filter window

where a1 - a9 are gray levels of each pixel in the filter

window

Apply the templates to a 3x3 filter window.

X = -1*a1 + 1*a3 - 2*a4 + 2*a6 - 1*a7 + 1*a9

Y = 1*a1 + 2*a2 + 1*a3 - 1*a7 - 2*a8 - 1*a9

Sobel Gradient = sqrt (X*X + Y*Y)

Note: In order to filter pixels located near the edges ofthe image, edge pixel values are replicated to givesufficient data.

Prewitt Edge Detector Filter

creates an image where edges (sharp changes ingray-level values) are shown. Only a 3x3 filter size canbe used with this filter.

This filter uses two 3x3 templates to calculated thePrewitt gradient value, as shown below:

Table 15.

-1 0 1 -1 0 1 -1 0 1 X

1 1 1 0 0 0 -1 -1 -1 Y

Templates

Table 16.

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a1 a2 a3 a4 a5 a6 a7 a8a9 3x3 filter window

where a1 - a9 are gray levels of each pixel in the filterwindow

Apply the templates to a 3x3 filter window.

X = -1*a1 + 1*a3 - 1*a4 + 1*a6 - 1*a7 + 1*a9

Y = 1*a1 + 1*a2 + 1*a3 - 1*a7 - 1*a8 - 1*a9

Prewitt Gradient = sqrt (X*X + Y*Y)

Note: In order to filter pixels located near the edges ofthe image, edge pixel values are replicated to givesufficient data.

Edge Sharpening Filter

uses a subtractive smoothing method to sharpen animage. First, an average filter is applied to the image. Theaveraged image retains all low-spatial frequencyinformation, but has its high-frequency features, such asedges and lines, attenuated. Consequently, the averagedimage is subtracted from its original image and theresultant difference image will primarily have the edgesand lines remaining. After the edges are deternimed inthis manner, the difference image is added back to theoriginal image to give an edge-enhanced image. Theresultant image will have clearer high-frequency detail;however, there is a tendency for noise to be enhanced.

Note: In order to filter pixels located near the edges ofthe image, edge pixel values are replicated to givesufficient data.

1. In the Maps tree, right-click an image layer and clickFilter.

2. In the Filter dialog box, enter an X- and Y-filterkernel size in the Filter size spin boxes.

3. Click the High Pass tab.4. Enable a filter option.5. Click Apply to View.

The high-pass filter changes the image in the viewpane. You can save a filter view by clicking Applyto File.

The Save New Filtered Image Layer dialog boxopens. You can either save the filtered image to anew image layer, or overwrite the existing layer.(See Creating custom filters on page 256 andSavinga filtered image to a new file on page 257 )

Creating custom filters

You can design your own filter by specifying thecoefficients for a filter template. Custom filters performspatial filtering on each pixel in an image using thegray-level values from either a square or a rectangularkernel surrounding each pixel.

Some common custom filters are

• Weighted average• Directional• Center weighted

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1. Click the Custom tab.2. Enter your filter parameters in the matrix provided.

For example, for a 3x3 filter you can use a1 a2 a3,a4 a5 a6, or a7 a8 a9, and so on.

When you enter a range of a1 - a9, the filter isplaced over the image so that the target pixel iscovered by a5. The neighbourhood pixels are thenmultiplied by the corresponding values in the filterand then summed. The pixel at a5 is replaced bythis sum.

3. To read a kernel from a specific file, click Import.

The number of entries in the first line of the filedetermines the number of columns in the kernel. Alllines of data that follow have the same number ofentries. If there are more, they are ignored. If thereare less, then zeros are used to make up thedifference. Data entries should be separated byspaces, tabs, or new lines.

4. To write a kernel to a file, click Export.5. Click Normalize.

The Normalize button divides all entries by the sumof the kernel entries. All other filtering algorithmsnormalize their respective kernels before performingthe filtering operation.

You can reset kernel entries to zero by clickingReset.

(See Saving a filtered image to a new file on page 257 )

Saving a filtered image to a new file

Save New Filtered Image is used to select where theoutput of the applied filter should be saved. A file andchannel must be specified for each color elementcomposing the filtered layer: three for RGB layers andone for grayscale and PCT layers.

1. From the Filter dialog box, click Apply to File.2. In the Save New Filtered Image dialog box, choose

a file from the File list box.

If a file is not listed, click Browse, locate and selectit, and click Open.

3. Choose a layer from the Layer list box.

If you want to create a new layer, choose NewLayer and enable the Load filtered layer checkbox.

4. Repeat steps step 2 and step 3 for the remainingchannels.

5. Click OK.

Scaling imagesRemote sensing data is structured in 8-bit, 16-bit, and32-bit formats. There are many instances where you mayneed to scale data from a higher to a lower bit depth. Forexample, you can prepare data for visual display byscaling it from 16-bit or 32-bit to 8-bit. You can also scaledata to a lower bit depth before you export it toapplications that do not support data bits greater than 8.Scaling will let you change 32-bit real data from a realnumber to a whole number and you can scale to reducethe size of your imagery. However, there is a risk oflosing information when you scale to reduce file size.

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Image Data and Scaling

For 8-bit data, the digital numbers (DN) assigned to eachpixel are between zero and 255. For 16-bit data, DNs canfall between zero and 65,535. Because eyes are notsensitive to subtle differences in grayscale or color, wecannot visually benefit from images composed ofthousands of shade variations.

Focus can also perform color and shade scaling to helpyou control a large range of data values. Scaling animage often makes the data easier to manage andinterpret.

Scaling output data using Save As

The Save As dialog box lets you scale data to a new bitdepth while letting you preserve the original version.Scaling data is a two-part process. Once a destinationfolder for your output is chosen, you can choose availableGDB options in the GDB Options Editor. You then selectthe bit depth for the scaled output by applying newproperties.

Using the Output Layer Properties panel, you can choosethe layer you want to scale, set your output to 8- bit,16-bit, or 32- bit, and choose a scaling method.

1. From the Maps tree, right-click the layer you want toscale and click Save As.

2. In the Save As dialog box, choose a file from theFile list box.

If an output file is not listed, click Browse, locate

and select it, and click Save.

3. Choose a format from the Format list box.

If you want to reconfigure a format, click Optionsand make any changes in the GDB Options Editor.

4. Click Properties.5. In the Output Layer Properties dialog box, choose

a bit-depth for your output from the Output type listbox.

6. Choose a scaling method for your output from theScaling list box.

7. Click OK.

Available scaling methods

LIN:

The linear function scales data values equally from theinput range to the output range. Other non-linearfunctions also perform compression and/or stretching.

SQR:

The square function compresses the lower end ofspectrum and stretches the upper end. The image graylevels are shifted towards the lower end so the imageappears darker in comparison to the linearly scaledresult.

ROOT, LOG:

The logarithmic and square root functions compress theupper end. The square root is stronger than logarithmic,so the image is made brighter.

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NQ:

The automatic normalized quantization methodtransforms a typical input image of a unimodal histograminto a near-symmetric, Gaussian-like distribution with themedian input level transformed to the mid-point of theoutput range. The algorithm applies a smooth nonlinearfunction to gradually compress the extreme high or lowportions of input range. The middle portion of the datarange is mapped with little distortion. This method isrecommended for image quantization to a lower numberof gray levels. It is robust in handling 32-bit input images.

EQ:

The equal-area quantization method maps an image tothe output range with an equalized output histogram. Forexample, each output level has approximately the samenumber of pixels.

POW:

The general power function fine-tunes the amount ofcompression and shifting each way with a user-suppliedexponent value. If the exponent is greater than 1, theeffect is shifting down; if the exponent is less than 1, theeffect is shifting up.

For both the input and output the entire range of digitalnumbers (DN) is used in determining the range. Usingthe Save As feature may be appropriate for scaling to8-bit data, but situations may arise where you needcontrol of the input and output range. If this is the case,you must use the SCALE algorithm in the Algorithm

Library.

Scaling output data

A SCALE algorithm is available in the Algorithm Library.In some cases, you may want to use the SCALEalgorithm instead of the Save As method, as it gives youmore control when scaling an image by allowing you tospecify your input minimum and maximum and youroutput minimum and maximum values. Additionally, youwill be able to specify the left and right tail trimming, thescaling function, and the bit depth for the output layer.

SCALE maps the gray levels of an input image to thegray levels of an output image. The typical use of thisprogram is to scale/quantize imagery in a high-resolution(32-bit or 16-bit) channel down to a fewer number of graylevels to fit into a low-resolution (16-bit or 8-bit) channel.SCALE can also be used to stretch or shift the dynamicrange of an input image for visual enhancement.

If you have a Geomatica Prime license, you can use theSCALE program in the Algorithm Library.

Minimum and Maximum Input Gray Level Values:

If Minimum Input Gray Level Value and Maximum InputGray Level Value are set as the default, the SCALEalgorithm calculates the range from the image data basedon the tail-trimming levels.

If the number of input channels is greater than one andboth Minimum Input Gray Level Value and Maximum

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Input Gray Level Value are specified, this range is usedfor every input channel.

Tail Trimming:

Optionally specifies the amount of tail trimming of inputimage histogram before scaling. If Minimum Input GrayLevel Value and Maximum Input Gray Level Value arespecified, the specified input range is used, while Left TailTrimming% and Right Tail Trimming% are ignored. If thetwo trimming parameters are not specified, the minimumand maximum of image data for every input channel isused for input range.

The two trimming parameters are useful only for scalingalgorithms (LIN/SQR/LOG). The two quantizationalgorithms squeeze tails automatically.

Minimum and Maximum Output Gray Level Value:

Specifies the minimum and maximum output gray-levelvalues after scaling. If the number of channels is greaterthan one, the values are used for every output channel.

Scaling Function:

Specifies the scaling function or quantization algorithm.

The following scaling functions are available

• #d289e3_id on page 258 Linear.• #d289e3_id on page 258 Square.• #d289e3_id on page 258 Square root and

Logarithmic.

• #d289e3_id on page 258 Power with a specifiedexponent as defined by Exponent.

• #d289e3_id on page 258 Automatic normalizedquantization

• #d289e3_id on page 258 Equal-area quantization

Output Type:

Specifies the sub-data type of one or more resultingimages.

• 8-bit unsigned• 16-bit signed• 16-bit unsigned• 32-bit real

1. Open SCALE from the Algorithm Library.2. Select one or more raster layers for scaling.3. Fill in the input parameters for the file.4. Run SCALE.5. Right-click the new layer and click Save.

Fusing image dataThere are two algorithms you can run from the AlgorithmLibrary that can fuse different data files into a new file.The Raster Calculator lets you work with raster data inthe spectral domain, while providing indices such as theNDVI Leaf Area Index. This section provides informationon using the Raster Calculator tool, the IHS-FUSE, andthe PANSHARP algorithms.

Running the FUSE algorithm

Intensity/Hue/Saturation-FUSE performs data fusion ofan input RGB color image on an input file with a

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black-and-white intensity image The result is an outputRGB color image with the same resolution as theintensity image. If the input and output files are different,the input RGB color image is resampled using thespecified resampling method. Either the Hexcone orCylinder IHS color model is used for data fusion.

IHS converts red, green, and blue image channels tointensity, hue, and saturation image channels, whichenhances and controls the output colors for a given set ofinput red/green/blue imagery.

CYLINDER was the original method used by the IHS andRGB programs in previous PCI software releases(Version 6.0.1 and earlier). The Hexcone model is usedby many commercial image processing softwareprograms. One model can produce more visuallypleasing results than the other, depending on thecircumstances. The Hexcone model runs about 15%faster than the Cylinder model.

Running FUSE is similar to running IHS and RGB. IHSseparates an RGB channel into three color spacecomponents (intensity, hue, and saturation) and placeseach in a separate channel. The RGB program can thenbe used to convert intensity, hue, and saturation channeloutput by IHS back to red, green, and blue channels. TheIHS and RGB programs can enhance and control theoutput colors more easily for any three channels in animage database file.

In computer imaging, colors are produced ascombinations of the additive primary colors (red, green,and blue). Another means of color definition is in terms of

intensity, hue, and saturation.

Intensity is the lightness or darkness of a color. Forexample, in an axis that is equidistant from the threeprimary color axes, which are orthogonal or perpendicularto each other, zero intensity represents black. As theintensity is increased, the lightness increases and thedarkness decreases. Full intensity (for 8-bit data, this is255) represents white.

Hue refers to an actual color and is defined as an angleon a circle that is centered and perpendicular to theintensity axis. For the Hexcone model, zero degreesrepresents red and hue values cycle throughRed-Green-Blue-Red; whereas, in the Cylinder model,zero degrees represents blue and hue values cycle in theopposite direction through Blue-Green-Red-Blue. Thefollowing table shows the unscaled and scaled huevalues for both IHS models:

Table 17.

HueAngle

HexconeUnscaled

ModelScaled

CylinderUnscaled

ModelScaled

Red 0 0 240 170

Yellow 60 42 180 128

Green 120 85 120 85

Cyan 180 127 60 42

Blue 240 170 0 or 360 0 or 255

Magenta 300 212 300 212

Red 360 255 240 170

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Saturation is the amount of color present or the radius ofthe circle described by the hue. Zero saturationrepresents no color and would appear as a gray shadedepending on the associated intensity; full saturation (1.0for unscaled Hexcone model or 208.2066 for 8-bitunscaled Cylinder model) represents full color.

Full saturation accentuates the RGB components at theexpense of other hues, in that other hues peak in theirsaturation at less than the maximum possible saturation.

IHS is an easier means of controlling the output colorthan RGB. For example, it is easier to comprehendlightening an image (increasing the intensity) or addingmore color (increasing the saturation) than it is tocomprehend the effects of increasing or decreasing theRGB values. One possible application of IHS is toproduce channels from three input channels, stretch thesaturation channel, and then convert the IHS channeldata back to the equivalent RGB channels for videodisplay. The output image would have a better saturationrange without changing the colors of the original image.

The following diagram shows the geometric relationshipbetween the RGB and IHS coordinate systems forrepresenting color. The hexcone or cylinder is oriented sothat the angles between the Intensity axis and theprimary RGB color axes are the same. The Saturationaxis is perpendicular to the Intensity axis. Hue is theangle between the radius of the circle defined by theRGB value and the Saturation axis.

Geometric relationship between RGB and IHS

1. With a multispectral and panchromatic imagesopen, open the Algorithm Library, and locate anddouble-click FUSE.

2. Select the panchromatic image layer as input to theIntensity Layer.

3. Select the multispectral image layers as input intothe Red, Green, and Blue image layers.

4. Click the Input Params 1 tab and choose a type ofresampling you want to use from the ResampleMode list box.

5. Choose a model from the IHS Model list box.6. Click Run.

An advantage of running IHS and RGB instead of only

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running FUSE is that you can enhance the output fromIHS individually, and then use the enhanced output inRGB.

Running IHS and RGB

1. With multispectral and panchromatic images open,open the Algorithm Library, and locate anddouble-click IHS.

2. Select three image layers from your multispectralfile for the red, green, and blue input layers.

3. Click the Input Params 1 tab and choose a type ofresampling you want to use from the ResampleMode list box.

4. Click Run.5. Open the Algorithm Library, and locate and

double-click RGB.6. Select a high-resolution panchromatic image layer

as input for the intensity layer.7. Select hue and saturation outputs from IHS as the

inputs for the hue and saturation input layers.8. Click the Input Params 1 tab and choose a type of

resampling you want to use from the ResampleMode list box.

9. Specify the output bit depth.10. Click Run.

Using the PANSHARP algorithm

PANSHARP fuses high-resolution panchromatic imagerywith multispectral imagery, creating a high-resolutioncolor image. This technique is often referred to aspan-sharpening. This program was designed to work with8-bit, 16-bit, or 32-bit real data. Panchromatic data can

be fused with multi-spectral imagery simultaneouslyacquired by the same sensor or with images fromdifferent sensors. The best results is achieved when theimagery is collected simultaneously and the resolutions ofthe panchromatic and multispectral data are closelymatched. The spectral characteristics of the original datawill be preserved in the resulting high resolution colorimagery. This means that analysis such as classificationcan be done on the pan-sharpened imagery with theadded benefit of higher spatial resolution.

For more information, visit the PCI Web site athttp://www.pcigeomatics.com/support/quickguide/pansharp.pdf.

For information about orthorectifying QuickBird andIKONOS data for QuickGuides, go to:

http://www.pcigeomatics.com/support/quickguide/QuickBird.pdf

http://www.pcigeomatics.com/support/quickguide/IKONOS_Help_v2.pdf

Note: Landsat 7 pan and ms data is co-registered at thesatellite; therefore, the geocorrection step is notnecessary when using this data.

1. Ensure the panchromatic (PAN) channel andmulti-spectral (MS) channels are co-registered,geo-corrected, or orthorectified.

2. Open the PAN and MS images.3. Open the Algorithm Library, and locate and

double-click PANSHARP.

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4. Choose the pan image channel from the InputPanport.

The input reference image channels should beselected so that the ms bands cover the frequencyrange of the panchromatic channel as closely aspossible.

The channel number given in the above table is thestandard ordering on the sensor and may differ fromthe order in an actual data file.

5. Select the MS channels to use in the Input port.

The best pan-sharpening results are obtained fromMS channels whose wavelengths lie within thespectral frequency range of the pan data.

6. The output can either be sent to the viewer or canbe saved to a new .pix file.

Note: To avoid reducing the radiometric resolution of thedata, process and save all the image bands in signed 16bits. Testing demonstrated that 16 bits for intermediatedata are enough; 32 bits are not necessary.

The following is a list of the reference bands forsome well-known satellite sensors:

Table 18.

Sensor Reference Bands

Landsat 7(ETM+)

Green 2 Red 3 Near IR:4

SPOT 1,2, 3

Green 1 Red 2

Sensor Reference Bands

(HRV)

SPOT 5(HRG)

Blue 1 Green 2

IRS 1C,1D

Green 1 Red 2

IKONOS Blue 1 Green 2 Red 3 Near IR:4

QuickBird Blue 1 Green 2 Red 3 Near IR:4

There is only one optional parameter in the InputParams1 tab. For a description of the No data image valueparameter, see PANSHARP in the online Help.

The automatic image fusion algorithm was developed byDr. Yun Zhang from the University of New Brunswick. Formore information and comparative results, see the belowreferences:

• Zhang, Yun. Problems in the fusion of commercialhigh-resolution satellite, Landsat 7 images, andinitial solutions. ISPRS, Vol. 34, Part 4, #GeospatialTheory, Processing and Applications#, Ottawa,2002.

• Zhang, Yun. A new automatic approach foreffectively fusing Landsat 7 and IKONOS images.IEEE/IGARSS'02, Toronto, Canada, June 24-28,2002.

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Using the raster calculatorThe Raster Calculator lets you formulate, write, and runcalculations based on data associated with raster files. Itprovides a graphical interface where you can createexpressions for working with any raster data, such asspectra data and digital elevation models (DEM).

When you build an expression, either type the expressionin the Expression box or build the expression by clickingthe buttons and items in the dialog box. Combining thetwo methods may cause unwanted effects.

The Raster Calculator also provides indices, such as theNDVI Leaf Area Index. You can calculate results for thesimplest raster arithmetic or the most complex equationsand your output can be a number, a 2D image, or both.The following table shows a list of the Raster Calculatorcategories and their associated functions.

Table 19.

Category Functions

Attribute Statistics

FieldValue - min, max,mean, sum, mode, std,median, count, first, last,wgtavg

Channel StatisticsChannel - min, max, mean,sum, mode, std, median,count

Constants E, PI, 2*PI, PI/2, PI/4

Conversion Rad2Deg, Deg2Rad,

Category Functions

Feet2Meters, Meters2Feet

Division Div, Mod

Exponential Exp, Pow, Sq(a), Squr, Sq(a,b), hyp

Extreme Min, max, round, floor, ceil

Hyperbolic Cosh, Sinh, Tanh, ACosh,ASinh, ATanh

Logarithmic Ln, Log, Alog

Random Rand, Seed

Rational If a = b, If a <> b, If a > b, Ifa < b, If a >= b, If a <= b

Sign Abs, Neg, Sgn

Trigonometric Cos, Sin, Tan, ACos,Asign, Atan, Atan2

Special Values

@x, @y, @dbx, @dby,@meterx, @metery,@geox, @geoy, @sizex,@sizey

Variables String, integer, float,double

(See About the raster calculator on page 265 )

About the raster calculatorThe Raster Calculator can be used in either basic or

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advanced mode. Advanced mode provides morecategory and function options and allows you to choosefrom several attributes that can be used in yourcalculations.When you use the Raster Calculator, newoutput layers are added to the Focus window.

Expression

The Expression menu lets you start a new expression,open a saved expressions, export an expression as andEASI file (.eas), and run an expression on chosen data.

New:

Starts a new Expression sessions.

Open:

Opens saved expressions.

Save:

Opens the New Expression Name dialog box to save anexpression.

Save As:

Opens the New Expression Name dialog box to eithersave an expression or save an expression with a newname.

Export to EASI:

Opens the File to Save dialog box to save an expressionusing the EASI file format (.eas)

Run:

Runs the expression you are working with on the datayou have selected in the Channels and Bitmaps list. (SeeChannels and Bitmaps)

Run and Close:

Runs your expression and closes the Raster Calculator.

Close Window:

Closes the Raster Calculator.

Edit

The Edit menu lets you work with the text in theExpression area. You can undo text edits, cut, copy,paste, and delete text in your expression.

Undo:

Cancels the last action within the Expression area.

Cut:

Cuts selected text in the Expression area.

Copy:

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Copies the selected text in the Expression area.

Paste:

Pastes cut or copied text at the cursor location.

Delete:

Deletes selected text in the Expression area.

Select All:

Selects all the contents of the Expression area.

View

The View menu lets you choose either basic or advancedmode for the Raster Calculator.

Basic:

Changes the Raster Calculator to Basic mode.

Advanced:

Changes the Raster Calculator to Advanced mode.

Raster Calculator toolbar

The Raster Calculator toolbar lets you start newexpressions, open saved expressions, save expressions,run expressions, and stop expression operations.

New:

Starts a new expression.

Open:

Opens the Expression name dialog box, where you canselect a saved expression from a list.

Save:

Opens the New Expression Name box so that you canenter name for a new expression.

Run:

Runs the expression you have selected.

Stop:

Stops an expression operation.

Expression

The Expression area shows the numeric values and theexpressions used in a calculation. You can add valuesand, in Advanced mode, you can add expressions byselecting a category and choosing a function.

Input:

Lets you choose file data and specify the layers of a file.

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Browse:

Opens the File Selector dialog box.

Channels and Bitmaps:

Lets you choose a channel or bitmap from the list for theexpression.

Attributes:

Lists the attributes in the data.

Calculator keys

The Raster Calculator Keys include most standardcalculator keys and numbers. In Advanced view,additional functions are available. Advanced functions aredivided into 15 categories.

Categories:

Lets you choose a category of functions you can use inyour expression.

Functions:

Lists the functions for the category you have chosen.

Output parameters

The Output parameters area lets you set the parametersfor your Expression output data.

Single Value:

Gives a numerical output value. When you disable thecheck box, the Mask, Type, Display, and Save optionsare available.

Mask:

Lets you choose a bitmap mask from within your sourcedata.

Type:

Lets you choose the bit depth of your output raster data.

Display:

Shows the output of your expression in the view pane.

Save:

saves the output to a selected file and layer.

Display Saved Results:

Opens your results in the view pane after you have runan expression.

File:

Lets you choose a target output file.

Browse:

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Opens a File Selector dialog box, where you can choosea target output file.

Layer:

Lets you select a target output channel.

Status bar:

Reports single-value results and the status of anexpression.

Using the Raster Calculator to set outputparameters

The Single Value option gives you a single-number resultfor a single-band computation in the status bar of thecalculator tool.

Display:

Is the result of a computation on one or more bands thatproduces a band. This output field can be saved to diskand can be shown in the Focus window.

1. From the Tools menu, click Raster Calculator.2. Click in the Expression box.3. Using the calculator buttons, enter an equation in

the Expression box and specify Add to existingfile.

4. Enter an equation in the Expression box andspecify Add to new file, channel description, andchannel type into the output parameters.

5. Enter an equation in the Expression box thatresults in a single integer value.

When no output parameters are specified, theRaster Calculator checks for errors in the equation(such as parentheses not closed), calculates theresult, and displays it in a new window.

Many of the same formatting rules for EASI Modelingapply to the Raster Calculator. (See Opening the EASIModeling dialog box on page 269 )

Opening the EASI Modeling dialogbox

You can use the EASI scripting language to write scriptsand run them on data you have open in Focus. You canalso open the EASI Modeling dialog box to run EASIscripts for data that is not open in Focus. Dozens ofpre-written scripts are available in the Geomatica V10.0pro folder.

EASI Modeling uses a single input file. The model isperformed directly on the database file. It isrecommended that you keep a copy of the original inputfile before running the model. You can also test themodel using bitmaps instead of image layers, whereapplicable.

The Modeling window provides the option of displayingthe results to the view pane. It is not necessary to savethis new layer back to the database, as the modelingprogram operates directly on the database file, rather

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than the display. When you review the results on-screen,you can delete the new layer by right-clicking the layer inthe Maps tree and clicking Remove.

For details on numeric, string, logical, and modeling(channel, bitmap and special variable) expressions, seethe EASI topic in the Geomatica Help.

The online Help provides details on the entire EASIscripting language. EASI Modeling is designed primarilyfor simple image modeling. While all options are availablefor PACE MODEL scripts run at the EASI prompt, only asubset of these commands can be used in the EASIModeling window.

For more information on EASI Modeling with Geomatica,go to http://www.pcigeomatics.com/support/quickguide/EASIModelinginFocus.pdf on the PCIGeomatics Web site.

1. From the File menu, click Open.2. In the File Selector dialog box, locate and select

the file on which you want to run an EASI script, andclick Open.

The image and bitmap layers must exist in thedatabase .pix file prior to running the model.

3. From the Tools menu, click EASI Modeling.

About the EASI Modeling dialog box

The EASI Modeling dialog box allows you to view EASIModels as text. You can load and edit previously writtenscripts, select input data, run scripts, save scripts andscript changes, and have the results opened in the view

pane.

Input File:

Lets you select an input file from the list box.

Browse:

Opens the File Selector dialog box.

Run:

Runs the EASI script loaded in the EASI Modeling dialogbox.

Clear:

Clears all text appearing in the EASI Modeling dialog box.

Load:

Opens a File Selector dialog box, where you can selectpre-written or saved EASI Modeling files.

Save:

Saves scripts opened in the EASI Modeling dialog box.

Save As:

Lets you save an EASI script using another file name.

Display Results:

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Opens the output of the EASI script.

Close:

Closes the EASI Modeling dialog box.

Adding image and bitmap layers to a .pix file

1. From the Files tree, right-click a file and click Newand then click Image Layer (or Bitmap Layer).

2. From the Tools menu, click EASI Modeling.3. In the EASI Modeling dialog box, from the Input

File list, choose an input file from the Input File listbox.

4. Click in the model box and type a model (forexample, %12=(%1-%2)/(%1+%2);).

If you want to display the model results in the viewpane, enable the Display Result check box.

5. Click one of the following buttons:• Run: executes the model• Clear: clears the model box• Load: opens an existing model with files using

the .eas file name extension• Save: saves the model to a text file using the

.eas file name extension

Using simple image models

Modeling equations, in their simplest form, are arithmeticcombinations of image layers assigned to other imagelayers. Image layers are indicated by a percent signfollowed by the layer number. The following equation

assigns the average numeric value of image layers 1 and2 to image layer 3.

%3 = (%1 +%2)/2

The assignment is evaluated for every pixel in imagelayer 3, using the corresponding pixel values from imagelayers 1 and 2.

You can also assign a constant value to an entire imagelayer.

%1 = 255

A standard set of arithmetic operations is available inmodeling expressions:

a + b Addition

a - b Subtraction

a * b Multiplication

a / b Division

a ^ b Exponentiation

(a) Parentheses, also square brackets [].

- a Unary negation

The following mathematical intrinsic functions are alsoavailable:

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sin(), cos(), tan(), asin(), acos(), atan(), ln(), log10(),exp(), exp10(), rad(), deg(), abs(), int(), random() andfrac()

All the rules previously indicated for image layers alsoapply to bitmap layers, except that the variables areprefixed with two percent signs instead of one. A bitmaplayer can have a value of either 1 (ON) or 0 (OFF). Forexample, if image layer 1 has a digital number greaterthan 50, then set bitmap layer 15 to 1.

If %1 > 50 then

% %15 = 1

endif

Understanding the basic modeling logic

In addition to using simple assignment equations, youcan also construct simple logical operations in the EASIModeling dialog box. These operations take the form of'IF' statements.

The following command sets the numeric value of imagelayer 2 to 255 anywhere the value of image layer 1 isbetween 32 and 64. Line breaks are significant; eachstatement must be on its own line.

if (%1 >= 32 AND %1 <= 64) then

%2 = 255

endif

The following example shows a more complex procedureto turn on bitmap layer 2 (%%2), where image layers 1, 2,and 3 are equal to 255.

if (%1 = 255) and (%2 = 255) and (%3 = 255) then

%%2 = 1

else

%%2 = 0

endif

The possible comparison and logical functions are:

a > b a greater than b

a < b a less than b

a = b a equals b

a <> b a not equal b

a <= b a less than or equal b

a >= b a greater than or equal b

a OR b a is true or b is true

a AND b a is true and b is true

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!a a is not true

You can also use brackets to ensure operations takeplace in the expected order.

Detailed Examples

In the following example, a 'Vegetative Index' calculationusing image layers 1 and 2 is performed and the resultsare saved to image layer 13 of the same file. Next, a32-bit real image layer is added to the sample data fileirvine.pix to store the results.

1. With irvine.pix open, click the File tab.2. Right-click irvine.pix and click New and then click

Raster Layer.3. In the Add Image Channels dialog box, enter a 1 in

the 32 bit real box and click Add.4. From the Tools menu in the Focus window, click

EASI Modeling.5. In the EASI Modeling dialog box, enter the

following model in the model box:• %13=(%1-%2)/(%1+%2);

To output to an 8-bit image layer, some scaling andadjustment is necessary.

6. Click Run.

Adding a bitmap layer to irvine.pix

• From the Files tree, right-click irvine.pix and clickNew and then click Image Bitmap Layer.

To view the results in the view pane, enable the Display

Results check box.

if (%1 < 55) and (%2 < 55) and (%3 < 55) then

%%33 = 1

else

%%33 = 0

endif

The demo file irvine.pix does not contain a black 'nodata' area outside the image. For the purpose of thefollowing example, a digital number of less than 55 inimage layers 1, 2, and 3 was used to create the bitmaplayer. If you are creating an actual mask for the 'no data'area, you use (%1 = 0) and (%2 = 0) and (%3 = 0) in theIF statement.

Change area under bitmap to white in image layers 1, 2,and 3;

if %%33=1 then

%1=255

%2=255

%3=255

endif;

Create a white grid on an RGB image:

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if (mod(@geox,1000)<=@sizex) or(mod(@geoy,1000)<=abs(@sizey)) then

%1 = 255

%2 = 255

%3 = 255

else

%1 = %1

%2 = %2

%3 = %3

endif

See 'Special Variables' for details on the use of @geox/@geoy & @sizex/ @sizey.

Blending examples

Create an image which smoothly blends image layer 1into image layer 2 as you move across the image. Theoutput is placed in image layer 8.

%8 = ((@x-1)/@dbx)*%2 + ((@dbx-@x)/@dbx)*%1

5) Create a gray level ramp of 0 to 255 across an imagelayer.

%8 = ((@x-1)*255) / @dbx

Perform a 3x3 smoothing filter on image layer 8. Backslashes are used to extend a statement over multiplelines. Also note that the Algorithm Library program FAVperforms this operation more efficiently.

%8 = (%4[@x-1,@y-1] + %4[@x,@y-1] + %4[@x+1,@y-1] + \

%4[@x-1,@y ] + %4[@x,@y ] + %4[@x+1,@y ] + \

%4[@x-1,@y+1] + %4[@x,@y+1] + %4[@x+1,@y+1] ) /9

When processing pixels on the border of the image, theneighbourhood of the current pixel extends off thedatabase. To ensure that referenced pixels that are offthe database (such as%4[@x-1,@y-1] in the top leftcorner) are usable, the image values are replicated outfrom the edge of the database to supply values that aremissing.

The following section describes EASI Modeling syntax inmore detail.

Image layer variables

Image layers can be specified in a modeling expressionusing any of the following forms:

%n [(x_expr, y_expr)]

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%{ n } [(x_expr, y_expr)]

%{ file_spec, n } [(x_expr, y_expr)]

The first case is the image layer sign (%) followed by aliteral numeric value, such as 1, 2 or 3, indicating layer 1,2, or 3 of the implicit database (such as the input file).The second example is similar, but the image layernumber may be a numeric expression that is evaluated tobe the image layer number.

The third case is more general yet. The file_spec may bea database file name or a file handle returned byDBOpen(), and the image layer number is evaluated asan expression(#n#).

For simple models, you cannot reference files other thanthe input file selected from the list box. EASI Modelinggenerally operates on a single file for both input andoutput. For example, you cannot run the following modelif your input file is D:\Geomatica_V82\demo\irvine.pix.

%13 = %{"D:\Geomatica_V82\demo\eltoro.pix", 1}

However, you can override this by using the DBOpen()function to open any number of database files. To copyimage layer 1 from eltoro.pix to image layer 12 inirvine.pix:

local integer fdinput, fdoutput

fdinput = DBOpen("D:\Geomatica_V82\demo\eltoro.pix","r")

fdoutput = DBOpen("D:\Geomatica_V82\demo\irvine.pix", "r+")

%{fdoutput,13} = %{fdinput,1};

call DBClose(fdinput)

call DBClose(fdoutput)

The irvine.pix file is 512x512 and eltoro.pix is1024x1024. The previous operation copies image layer 1of eltoro.pix to image 13 of irvine.pix, but becauseirvine.pix is the implicit database (such as the input file),the area of operation is 0, 0, 512, 512; only the top leftquarter of eltoro.pix is copied into channel 13 ofirvine.pix.

The second part of the image layer specification is anoptional subscript specification. In the above case, thedefault subscript specification used is x --> x, y --> y. Thesubscript specification allows you to indicate the pixel thatshould be operated on for the current value of X and Y,and may be given as an expression.

The following example assigns a sampled copy ofeltoro.pix to irvine.pix. The @x and @y symbols are thecurrent pixel location when the expression is evaluatedfor each pixel.

local integer fdinput, fdoutput

fdinput = DBOpen( "D:\Geomatica_V82\demo\eltoro.pix","r")

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fdoutput = DBOpen("D:\Geomatica_V82\demo\irvine.pix", "r+")

%{fdoutput,13} = %{fdinput,1}(@x*2+1,@y*2+1);

call DBClose(fdinput)

call DBClose(fdoutput)

X and Y vary from 0 to 511 as the implicit window ofoperation is 0, 0, 512, 512... the area of irvine.pix.However, image layer 1 of eltoro.pix is sampled forvalues of 1 to 1023. As @x and @y value from 0 to 511,the expression @x*2+1 varies from 1 to 1023.

It is also legal for the subscript expressions to extend ofthe source database. In this case image values from theedge of the database are replicated out as far as isneeded to satisfy requests. Thus, a simple filter such asexample 6 above the following will work in a reasonablemanner, even on the edge of the database.

Bitmap Layer Variables

Bitmaps layers are basically one bit deep image layers,used primarily to serve as masks for regions whereoperations are to take place and may be specified in amanner very similar to image layers. All the rulespreviously indicated for image layers also apply to bitmaplayers, except that the variables are prefixed with twopercent characters instead of one. Also, the indexnumber is the segment number of the bitmap layer to beused.

%%n [(x_expr, y_expr)]

%%{ n } [(x_expr, y_expr)]

%%{ file_spec, n } [(x_expr, y_expr)]

Bitmap layer variables will only assume values of zero orone. Any non-zero value assigned to a bitmap layer willbe treated as one.

Creating an EASI bitmap maskCreate a bitmap mask (segment 2) which is true (1)everywhere channels 1 and 2 are less than 25. Then thismask and the mask in segment 3 are used to determine aregion that should be zeroed in image channels 1 and 2.

if

(%1 < 25 and %2 < 25)

then

%%2 = 1

else

%%2 = 0

endif

if (%%2 = 1 and %%3 = 0)

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then

%1 = 0

%2 = 0

endif

Special Variables

Allow access to information about the size andgeoreferencing information of channels being operatedon and the position of the current pixel. The followingspecial variables may be treated as elements in modelingexpressions.

@x current x (pixel) processing location

@y current y (line) processing location

@dbx size of database in x (pixel) direction

@dby size of database in y (line) direction

@meterx size of a pixel in x direction in meters

@metery size of a pixel in y direction in meters

@geox x georeferenced centre of current pixel

@geoy y georeferenced centre of current pixel

@sizex x size of a pixel in georeferenced units

@sizey y size of a pixel in georeferenced units

Note that @x, @y, @geox and @geoy change value foreach pixel processed, while @dbx, @dby, @meterx,@metery, @sizex and @sizey remain constant over thewhole image.

It is usually necessary to use the @x and @y specialvariables when constructing subscript expressions forchannel expressions. For example, the followingassignment would mirror an image across a verticalcenter line. The @dbx is used in computing the centerline.

%2 = %1[@dbx-@x+1,@y]

Numeric Expressions

Numeric expressions in EASI are normally operated on indouble precision floating point. Values with less precisionare promoted to double precision before operations areperformed.

A wide set of built-in operations are available in numericexpressions and are listed below with a short description.

a + b Addition

a - b Subtraction

a * b Multiplication

a / b Division

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a ^ b Exponentiation

( a ) Parenthesis, also square brackets [].

- a Unary negation

A numeric element can be any of the following:

• A numeric constant.• An EASI variable of type byte, int, float or double.• An element of a numeric variable array.• A numeric intrinsic function.• A numeric user defined function.• A subscripted numeric parameter.

Numeric constants can be entered as decimal orscientific notation numbers with an optional negative sign.Scientific notation is denoted with the #E# or #D#character - for example 123000 can be written as 1.23e5,1.23 * 10 ^ 5

Comparison and logical functions

a > b a greater than b

a < b a less than b

a = b a equals b

a <> b a not equal b

a <= b a less than or equal b

a >= b a greater than or equal b

a OR b a is true or b is true

a AND b a is true and b is true

!a a is not true

Example

if (%1 = 255) and (%2 = 255) and (%3 = 255) then

%%2 = 1

else

%%2 = 0

endif

Logical

Logical expressions in EASI are used to computeTRUE/FALSE results for use with the IF and WHILEconditional statements. There is currently no way to storea pure logical value in an EASI variable. Logicalexpressions consist of comparisons between numericand string expressions combined with the use of thelogical operations AND, OR, and NOT.

The equality and inequality tests may be used with twonumeric expressions. The equal sign (#=#) is used to testfor equality, while inequality is tested with #<># or #!=#.

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Examples

If( %1 = 0 ) then

...

while( flag <> 1 )

...

The ">", "<", ">=" and "<=" operations may only beperformed on numeric expressions.

Examples:

while( total <= 100 )

while( total < 101 )

while( NOT total > 100 )

while( NOT total >= 101 )

The logical operations AND and OR operate on twological expressions, while NOT operates on one logicalexpression. The symbols #&#, #|# and #!# are consideredto be equivalent to AND, OR, and NOT.

Examples:

if( A = 1 AND B = 1 )then

...

endif

if( A = 1 & b = 1 )then

...

endif

The IF statement is used to conditionally executestatements.

IF( logical_expression )THEN

statement_list

[ELSEIF( logical_expression )THEN

statement_list]

[ELSE

statement_list]

ENDIF

logical_expr - a logical expression as described in#Logical Expression.#

statement_list - a list of one or more statements.

Each logical_expression is evaluated in turn until one ofthem evaluates to be true. When one is true, thecorresponding statement_list will be executed, and

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control will continue beyond the ENDIF. If none of thelogical expressions is true and an ELSE clause exists,the associated statement_list will be executed.

The WHILE command provides a general purposelooping construct.

WHILE( log_expr )

statement_list

ENDWHILE

log_expr - a logical expression which is evaluated beforeeach iteration of the loop.

The logical expression in the WHILE statement isevaluated. If the result is true, the statement list isexecuted; otherwise, control skips to the statementfollowing the ENDWHILE. Once the statement list hasbeen executed, control returns to the WHILE statement totest the logical expression again.

It is possible to jump into, or out of, the WHILE loop usingthe GOTO statement, but this is poor style and may notwork in future versions of EASI.

The FOR command provides a simple looping constructover a series of numeric values.

FOR iter_var = start_val TO end_val [BY incr_val]

statement_list

ENDFOR

iter_var - the iteration variable. This may be any numericvariable type, including a parameter.

start_val - this initial value to assign to the `iter_var'.

end_val - when `iter_var' passes this value, iterationstops.

incr_val - a value by which to increment `iter_var' eachiteration. The default is 1.

The FOR statement initializes the iteration variable to theinitial value, checks it against the end value, and if theend value is not exceeded it executes the statement list.When the ENDFOR statement is reached, the iterationvariable is increased by the increment value andcompared to the end value. If the end value is notexceeded, the statement list is executed again. The startvalue may be greater than the end value and theincrement value may be negative, but if the incrementvalue does not take the iteration variable value closer tothe end value each iteration, the FOR loop will neverterminate.

It is possible to alter the value of the iteration variableinside the FOR loop and also to use GOTO to escape orenter the loop, but this is poor style and may causeproblems in future versions of EASI.

Example:

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The following example runs the PACE task CLR on thefirst 128 channels of the PCIDSK file irvine128.pix ingroups of 16 channels at a time.

local i,j

valu = 0

file="C:\Geomatica_V82\demo\irvine128.pix"

for i = 1 to 128 by 16

for j = 1 to 16

dboc(j) = i + j - 1

endfor

run clr

endfor

Multiple statements

can be placed on the same line by separating thestatements with a statement separator. The back slashand semi-colon characters can be used interchangeablefor this purpose. A line of input may be almost any length.

Examples

File = "C:\Geomatica_V82\demo\irvine.pix" \ run clr

File = "C:\Geomatica_V82\demo\irvine.pix"; run clr

Single Statements

You can split very long statements over multiple lines byplacing a back slash character, not a semi-colon, at theend of each incomplete line.

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Chapter 7Understanding atmosphericcorrectionThe data obtained by optical satellite sensors with highspatial resolution has become an invaluable tool for manygroups interested in studying, managing, developing, andprotecting our population, environment, and resources.Unfortunately, satellite images are often obscured byatmospheric effects like haze as a result of conditions inthe atmosphere at the time the image was captured.Atmospheric correction is a process used to reduce oreliminate atmospheric effects and reveal more accuratesurface reflectance values.

Two atmospheric correction processes are available:ATCOR2, which is used for correcting satellite imageryover flat terrain, and ATCOR3, which is used forcorrecting satellite imagery over rugged terrain. Both arealgorithms that work with a database of atmosphericcorrection functions, which are stored in lookup tables.The algorithms have been developed mainly for satellitesensors with a small swath angle such as Landsat andSPOT, but some wide field-of-view (FOV) sensors suchas IRS-WiFS are supported as well.

For more information on the atmospheric correction,please see the following articles:

R. Richter, 'A spatially adaptive fast atmosphericcorrection algorithm' Int. J. Remote Sensing, Vol. 17,1201-1214 (1996)

R. Richter, 'Atmospheric correction of satellite data withhaze removal including a haze/clear transition region',Computers & Geosciences, Vol. 22, 675-681 (1996)

R. Richter, 'Correction of satellite imagery overmountainous terrain', Applied Optics, Vol. 37, 4004-4015(1998)

Preparing data

Before you begin setting up the atmospheric correctionprocess, the data must be in one PCIDSK (.pix) file withall the channels in the same bit depth and resolution.Focus supports 8-bit unsigned, 16-bit unsigned, 16-bitsigned, and 32-bit real bit depths.

1. Transfer the data from the CD to PCIDSK (.pix)files, see Transfer data to PCIDSK on page 283 .

2. Reproject the thermal data, see Reprojecting dataon page 284 .

3. Assemble the data into one PCIDSK (.pix) file, seeAssembling data into a file on page 285 .

Transfer data to PCIDSK

You should import your images from the compact disk(CD) using the appropriate CD read algorithm. Eachsensor has its own CD read algorithm. It creates aPCIDSK file, imports the imagery channels from the CD,

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extracts the metadata, and saves the satellite pathinformation in a segment. By preparing your imagery thisway, Focus can automatically set or calculate severalparameters when you configure the atmosphericcorrection.

The number and types of bands on the CD depends onthe sensor used to capture the data. Usually, the visible,thermal, and panchromatic bands are in differentresolutions. Some sensors may not provide thermal orpanchromatic bands. Read the bands of the sameresolution at the same time into one file.

For example, Landsat 7 data usually has eight bands:bands 1 to 5 and 7 are the visible wavelengths with a30-meter resolution, band 6 contains two thermalwavelengths with a 60-meter resolution, and band 8 isthe panchromatic with a 15-meter resolution. You woulduse the CDLAND7 algorithm to read bands 1 to 5 and 7into a file, then band 6 into a file, and then band 8 into afile.

If you do not intend to use the thermal or panchromaticbands in the atmospheric correction process, then you donot need to read those bands into a file.

The CD read algorithms are available through EASI,Modeler, OrthoEngine, and Focus.

1. In the main menu, click Tools and then clickAlgorithm Librarian.

2. Under PCI Predefined in the Data Interchangefolder, open the CD Reading/Utilities folder.

3. Click the appropriate CD read algorithm for the

data.4. Click Open.5. Enter the required information on the Files and

Input Params 1 tabs.6. Click Run.7. Repeat for each set of bands with the same

resolution.

Reprojecting data

If you intend to use a thermal band in the atmosphericcorrection (ATCOR) process, you need to reproject it tothe same resolution as the visible bands. For Landsat 7data you can use either the high gain or low gain thermalchannels with ATCOR. For ASTER data use band 13.

For example, Landsat 7 thermal bands have a 60-meterresolution while its visible bands have 30-meterresolution. Therefore, the thermal bands have to bereprojected to a 30-meter resolution.

1. In the main menu, click Tools and then clickReprojection.

2. Click the Browse button beside Source file andselect the file that you want to reproject.

3. In the Destination file box, type the path and filename for the reprojected data.

4. In the Output format box, click PIX:PCIDSK.5. Under Reprojection Bounds, click Use bounds

and resolution in the list.6. In the Pixel Size boxes in the X and Y boxes, type

the new resolution.7. In the Resampling list, click the resampling method

of your choice.• Nearest: Nearest Neighbor resampling

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identifies the gray level of the pixel closest tothe specified input coordinates and assignsthat value to the output coordinates. Althoughthis method is considered the most efficient interms of computation time, it introduces smallerrors in the output image. The output imagemay be offset spatially by up to half a pixel,which may cause the image to have a jaggedappearance.

• Bi-Linear: Bi-linear resampling determines thegray level from the weighted average of thefour closest pixels to the specified inputcoordinates and assigns that value to theoutput coordinates. This method generates animage with a smoother appearance thanNearest Neighbor resampling, but the graylevel values are altered in the process, whichresults in blurring or loss of image resolution.

• Cubic: Cubic resampling determines the graylevel from the weighted average of the 16closest pixels to the specified inputcoordinates and assigns that value to theoutput coordinates. The resulting image isslightly sharper than one produced by Bi-linearresampling, and it does not have the disjointedappearance produced by Nearest Neighborresampling.

8. Under Source Layers, click Select All.9. Click Add.

10. Click Reproject.

Assembling data into a file

If you intend to use a thermal band in the atmospheric

correction process, you need to add the thermal band tothe file containing the visible bands. The thermal bandmust be in the same resolution as the visible bands. ForLandsat 7 data you can use either the high gain or lowgain thermal channel with ATCOR. For ASTER data useband 13.

1. From the Files tree, right-click the thermal channel.2. Click Export (Save As) and click To existing file.3. Beside Destination file click the Browse button

and select the file containing the visible bands.4. Under Source Layers, click Select All.5. Click Add.6. Click Transfer Layers.

Opening the Atmospheric CorrectionConfiguration dialog box

Before you begin setting up the process, you shouldimport your images from the compact disk (CD) using theappropriate CD read algorithm. For example, if you haveIKONOS imagery, you would use CDIKONOS to importyour images. By preparing your imagery this way, Focuscan automatically set or calculate several parameters.Also, the data must be in one PCIDSK (.pix) file with allthe channels in the same bit depth and resolution. Formore information, see Preparing data on page 283 .

Once your files are prepared, you can configure theAtmospheric Correction parameters. These parametersdefine the image to be corrected, the source of theelevation, the sensor information, the atmosphericconditions, and other required parameters.

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1. In the main menu, click Analysis.2. Click Atmospheric Correction.

Setting up atmospheric correctionparameters

1. In the Image file list, type the path and file name ofthe file that you you want to correct or click Browseto select a file.

2. If the image represents an area of flat terrain or ifyou do not have a digital elevation model (DEM) forthe image, click Constant(ATCOR2) and in theHeight box type a value representing a constantelevation for the area covered by the image.

3. If you do have a DEM for the image, click DEM(ATCOR3). In the File box click the file that containsthe DEM or click Browse to select a file. In theLayer list select the layer containing the elevationvalues.

4. To calculate Sky View and Shadow or to importSlope and Aspect calculations, click Setup. Formore information, see Calculating slope, aspect, skyview, and shadow on page 289 .

5. In the Units list, click the unit of measurement usedfor the elevation values.

6. In the Sensor type list, click the type of sensorused to collect the image.

7. If you did not use a CD read algorithm to importyour images, you may need to match the sensorband numbers to the correct image channelnumbers. To set up the channels, click BandSetup. For more information, see Matching bandnumbers to channel numbers on page 290 .

8. In Pixel size list, type the pixel size of the input

image.9. If the date is included in the metadata, the Date

boxes are set automatically. If not, in the Dateboxes click the month, day, and year when theimage was taken.

10. The Tilt list is available only when the sensorselected provides the tilt capability. If the sensorwas tilted when the image was taken, click the titleangle used in the Tilt list. If the metadata describesthe tilt angle in terms of left and right, right meansWest and left means East.

11. In the Calibration file list click the calibration file forthe image and sensor type or click Browse to selecta file. In most cases you can use the file with#standard# (or std) in the file name. For moreinformation, see Editing an existing calibration file tocreate a new file on page 292 .

12. In the Atmospheric definition area list, click theaerosol type for the image. For more informationsee About aerosol types on page 287 .

13. In the Condition list, click the standard atmospherepresent when the image was taken. For moreinformation see About standard atmospheres onpage 287 .

14. If you also selected a thermal band to correct, in theThermal atmospheric definition list click thestandard atmosphere present when the image wastaken. For more information see About standardatmospheres on page 287 .

15. If the date, time, and position are included in themetadata, the solar zenith value will be calculatedautomatically. If they are not, in the Solar zenithbox type the solar zenith value or click Calculate tocalculate the value (see Calculating the solar zenithand azimuth on page 290 ).

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16. (Available for ATCOR3 only) If the date, time, andposition are included in the metadata, the solarazimuth value will be calculated automatically. Ifthey are not, in the Solar azimuth box type thesolar azimuth value or click Calculate to calculatethe value (see Calculating the solar zenith andazimuth on page 290 ).

17. In the Visibility box type the visibility value. Formore information, see About visibility on page 291 .

18. In the Adjacency box type the adjacency value. Formore information, see About adjacency on page 291 .

19. (Available for thermal bands only) In the Offset tosurface temperature list, type the value used tocompensate for a systematic error in the conversionof radiance values to temperature values. For moreinformation, see Determining the offset to surfacetemperature value on page 291 .

20. Click OK.

About aerosol typesThe Atmospheric definition area list on the AtmosphericCorrection Configuration dialog box (see Opening theAtmospheric Correction Configuration dialog box on page285 ) contains the possible aerosol types for the image.The aerosol type is determined by the predominantparticles present in the area at the time the image wascaptured, which usually can be inferred its geographiclocation. Wind direction and weather conditions in thearea in the days before the image was taken can affectthe aerosol type present.

The aerosol types are:

• Rural: The rural aerosol type is composed mostly of

dust-like and organic particles. It is predominant incontinental areas whose atmosphere is not stronglyinfluenced by urban or industrial centers. It isrecommended for areas such as forested,agricultural, or snow-covered areas.

• Urban: The urban aerosol type is composed mostlyof particles such as sulfate aerosols resulting fromcombustion and industrial activities. If you do notknow the composition of the atmosphere, the ruralaerosol type is recommended.

• Desert: The desert aerosol type is composedmostly of large dust-like particles. If you do notknow the composition of the atmosphere, the ruralaerosol type is recommended.

• Maritime: The maritime aerosol type is composedmostly of sea-salt, dust-like and organic particles. Ifyou do not know the composition of theatmosphere, the rural aerosol type isrecommended.

About standard atmospheresThe Condition list and the Thermal atmospheric definitionlist on the Atmospheric Correction Configuration dialogbox (see Opening the Atmospheric CorrectionConfiguration dialog box on page 285 ) contain thestandard atmospheres used in Atmospheric Correction.Standard atmospheres are vertical profiles of pressure,temperature, water vapor, and ozone density.

The water vapor content present in the area plays a keyrole in determining which standard atmosphere to selectwhen performing an atmospheric correction. For sensorsthat do not include water vapor bands, you can estimatethe water vapor content based on the season when the

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image was captured and the location.

The standard atmospheres are:

• Dry or Dry Desert: A dry atmosphere has a totalwater vapor content of 0.41 (g cm-2).

• Fall (spring): A fall (autumn) atmosphere has atotal water vapor content of 1.14 (g cm-2).

• Humid: A humid atmosphere has a total watervapor content of 4.94 (g cm-2).

• Mid-latitude summer: A midlatitude summeratmosphere has a total water vapor content of 2.92(g cm-2).

• Mid-latitude winter: A midlatitude winteratmosphere has a total water vapor content of 0.85(g cm-2).

• Sub-Arctic summer: A sub-arctic summeratmosphere has a total water vapor content of 2.08(g cm-2).

• Sub-Arctic winter: A sub-arctic winter atmospherehas a total water vapor content of 0.42 (g cm-2).

• Tropical: A tropical atmosphere has a total watervapor content of 4.11 (cm or g cm-2).

• Arid: An arid atmosphere has a total water vaporcontent of 2.15 (g cm-2).

• US standard: The 1976 US Standard atmospherehas a total water vapor content of 1.42 (g cm-2).

Opening the elevation informationsetup dialog box

In ATCOR3 a digital elevation model (DEM) is used tocalculate the effect of radiance and transmittance overrugged terrain. The Slope and Aspect calculations are

mandatory for ATCOR3. The Sky View and Shadowcalculations are optional. These calculations can beautomatically calculated from the DEM or you can importthem in the Elevation Information Setup dialog box if youhave already created a file containing these values.

If you click Calculate for Slope, Aspect, Sky View, orShadow, PCIDSK files are automatically created in theuser folder where you installed Geomatica when youperform the atmospheric correction. By default each filename is the original input file name prefixed with 'slope_','aspect_', 'skyview_', or 'shadow_'.

The Slope algorithm measures the angle of the incline foreach pixel, which is expressed as a value between 0 and90 degrees. The value is calculated from the planeformed by the vector connecting the left and rightneighbours of the pixel and the vector connecting theupper and lower neighbours of the pixel.

The Aspect algorithm measures the orientation of theslope of each pixel, which is expressed as a valuebetween 0 and 360 degrees relative to the top of theimage. The value is calculated from the orientation of theplane formed by the vector connecting the left and rightneighbours of a pixel and the vector connecting the upperand lower neighbours of the pixel. The angle is measuredbetween north (top of image) and the projection of thenormal vector of this plane onto the horizontal plane.

The Sky View algorithm uses a ray tracing program todetermine the proportion of the sky hemisphere visible foreach pixel of the terrain.

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The Shadow algorithm uses a ray tracing program andthe solar zenith and azimuth angles to calculate the castshadows.

1. Open the Atmospheric Correction Configurationdialog box, see Opening the AtmosphericCorrection Configuration dialog box on page 285 .

2. Under Elevation Information Setup, click theSetup button.

Calculating slope, aspect, sky view, andshadow

1. In the File list under Elevation, click the file thatcontains the DEM or click Browse to select a file. Inthe Layer list select the layer containing theelevation values.

2. In a DEM each change in gray level represents achange in elevation value. In the Elevation stepbox, type the value that represents the change ofone level of gray.

3. Under Slope, either:• Click Calculate to calculate the slope values

automatically.• Click From file to import the slope values from

a file. In the From file list, click the file thatcontains the slope values or click Browse toselect the file. In the Layer list, click the layerof slope values.

4. Under Aspect, either:• Click Calculate to calculate the aspect values

automatically.• Click From file to import the aspect values

from a file. In the From file list, click the file

that contains the aspect values or clickBrowse to select the file. In the Layer list,click the layer of aspect values.

5. Under Sky View, either:• Click None if you do not want to include sky

view factor in the atmospheric correction.• Click Calculate to calculate the sky view factor

automatically.• Click From file to import the sky view factor

from a file. In the From file list, click the filethat contains the sky view factor or clickBrowse to select the file. In the Layer list,click the layer with the sky view factor.

6. Under Shadow, either:• Click None if you do not want to include

shadow data in the atmospheric correction.• Click Calculate to calculate the shadow data

automatically.• Click From file to import the shadow data from

a file. In the From file list, click the file thatcontains the shadow data or click Browse toselect the file. In the Layer list, click the layerof shadow data.

7. Click OK.

Opening the band setup dialog box

When you prepared the PCIDSK (.pix) file foratmospheric correction, the band numbers may notmatch the channel numbers. For example, band 1 fromthe sensor may not necessarily be in channel 1 in yourfile. You may need to match the sensor band numbers tothe correct image channel numbers.

1. Open the Atmospheric Correction Configuration

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dialog box, see Opening the AtmosphericCorrection Configuration dialog box on page 285 .

2. Under Sensor Information, click the Band Setupbutton.

Matching band numbers to channelnumbers

1. For each row under the Input Channel column,type the channel number that contains the sensorband corresponding to the band number under theSensor Band# column.

2. In the Output Corrected column, click to select therows corresponding to the channels that you want tocorrect. Rows identified by a check mark will becorrected.

3. If the NoData value is included in the metadata, itwill be entered automatically. If it is not, in theNoData Value column type the NoData value foreach channel in its corresponding row.

4. In the Gain Setting column, type the gain settingvalue from the header file.

The gain setting is only needed for the MOMS andAster sensors. It represents the offset between theimage and the calibration.

5. Click OK.

Opening the Solar Calculations dialogbox

The solar zenith and azimuth are important values usedin the atmospheric correction. If you imported you images

using a CD read algorithm, the values can be extractedfrom the metadata.

1. Open the Atmospheric Correction Configurationdialog box, see Opening the AtmosphericCorrection Configuration dialog box on page 285 .

2. Under Correction Parameter, click the Calculatebutton.

About Solar Zenith and Azimuth

The Solar Azimuth and Solar Zenith express the positionof the sun. The Solar Azimuth is the angle of the directionof the sun measured clockwise from the North along thehorizon. If the solar azimuth is measured from the South,usually referred to as the bearing, it will have to beadjusted since Focus assumes that North is the origin.The Solar Zenith is the angle measured between thelocal zenith and the line of sight of the sun.

Illustrating Solar Zenith and Solar Azimuth

Calculating the solar zenith and azimuth

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1. In the Date boxes click the month, day, and yearwhen the image was taken.

2. In the Time boxes, type hours, minutes, andseconds when the image was taken.

3. In the Latitude box, type the y-coordinate of thecenter of the image.

4. In the Longitude box, type the x-coordinate of thecenter of the image.

5. Click Calculate.6. Click OK.

About visibilityVisibility, or optical depth, is a meteorological statistic thatcalculates the opacity of the atmosphere at a certain timeand place. It measures the furthest distance that a personcan see a prominent object. In Focus the range isbetween 5 and 180 kilometers.

Focus uses the value set in the Visibility box. For moreinformation, see Opening the Atmospheric CorrectionConfiguration dialog box on page 285 for the SpatiallyVarying Conditions, and for Constant Conditions options,see Opening the Run Atmospheric Correction dialog boxon page 294 . When you use the Spatially VaryingConditions option, Focus calculates the visibility for eachpixel in the image using the Visibility value as a startingpoint for the calculation. When you use the ConstantConditions option, Focus uses the Visibility value as aconstant for each pixel in the image. The calculationresults in a Visibility layer that is a temporary PCIDSK(.pix) file with its default file name being the the originalfile name prefixed with 'hot_level_'.

Visibility is used to more accurately specify theatmospheric conditions at the time the image was taken.If the metadata that came with the image does notinclude the visibility values, you can obtain it from thefollowing sources:

USA: http://www.noaa.gov/wx.htmlCanada:http://www.weatheroffice.ec.gc.ca/canada_e.html

About adjacency

Adjacency is the effect of backscattering on neighboringpixels. It is used to more accurately specify theatmospheric conditions at the time the image was taken.

The adjacency effect is calculated for an area aroundeach pixel up to a maximum of 200 pixels. For example,an image with 30-meter resolution like Landsat will havea maximum Adjacency value of 6, because 200 multipliedby 30 meters is 6000 meters, which is 6 kilometers.Therefore, an Adjacency value of 0 would not take theadjacency effect into consideration while 6 wouldcalculate the maximum effect. The default is 1 and issuitable for most cases.

Determining the offset to surfacetemperature value

Occasionally there may be a consistent difference intemperature between actual temperatures measured onthe ground and those reported in the Spectral Plot. Toverify if you need to compensate for this difference, youneed to collect the temperature of identifiable points in

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the region at the time the image was captured. Thesetemperature samples are sometimes referred to as'ground truths'.

If you compare the ground truths to the results from thesame points collected on a temperature layer using theSpectral Plot, the temperature for each point in bothshould be the same. If you observe a consistentdifference in temperature, you can enter the value in theOffset to surface temperature box.

For example, you compare the actual water temperaturesof three lakes to their temperatures reported in theSpectral Plot and discover that there is a difference of 2degrees between the ground truths and the Spectral Plot.Therefore, you type 2 in the Offset to surface temperaturebox.

1. Configure and run the atmospheric correction. Formore information, see Opening the AtmosphericCorrection Configuration dialog box on page 285and Opening the Run Atmospheric Correctiondialog box on page 294 .

2. Position the cursor precisely on the feature that youcan clearly identify in the image for which you havea known ground temperature.

3. In the Maps tree, right-click the ATCOR MetaLayer.4. Click Spectra Plot.5. On the Atcor Spectra Plotting dialog box, click

From Image.6. Compare the actual temperature of the feature to

the temperature displayed under Report.7. Repeat step 2 to step 6 for each ground truth.

Editing an existing calibration file tocreate a new file

The standard calibration files are in the cal folder underthe atcor folder where you installed Geomatica (forexample, C:\Program Files\Geomatica_V100\atcor\cal).Each sensor has a set of calibration files created by Dr.Richter.

When you complete the Atmospheric CorrectionConfiguration dialog box, you can use one of thestandard calibration files since they are sufficient in mostcases. If you are not obtaining expected results, comparethe calibration coefficients (gain and bias values) in yourdata#s metadata file to those in the calibration file. If thevalues are significantly different, you can create you owncalibration file specific to your data.

The calibration file contains a table of the bands, the gainvalue for each band, and the bias for each band. ATCORuses mW/cm-2 sr-1 micron-1 as the radiance unit foreach band, except the thermal band which uses mW m-2sr-1 micron-1. Since the sensors may use a differentradiance unit, you may need to convert the values. Formore information, visithttp://www.op.dlr.de/atcor/atcor2+3_faq.html.

For example, some calibration coefficients are measuredin W m-2 sr-1 micron-1. To convert it to the ATCORradiance value, you multiply the values in the metadatafile by 0.1.

Example of a calibration file

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.

1. Open a standard calibration file for the sensorappropriate for your data.

2. Open the metadata file that came with your data.3. If required, convert the values from the metadata file

to ATCOR radiance units: mW/cm-2 sr-1 micron-1(or mW m-2 sr-1 micron-1 for thermal bands).

4. Replace the bias and gain values for each bandwith the converted values from the metadata file.

5. Save as a new file with the .cal extension in the calfolder in the folder for the appropriate sensor.

Opening the Define Haze and Clouddialog box

After configuring the parameters for atmosphericcorrection, you must create a mask over the hazy andcloudy areas in the image while excluding areas coveredby water or snow. Water and snow are identified by

comparing the water reflectance values in the NIR bandto the reflectance values in the snow band (1.6 um band).

In most cases the default values for reflectancethresholds will identify water and snow in image.However, you may have to iteratively adjust the thresholdvalues and recreate the mask to achieve the desiredresults.

1. In the Maps tree, right-click the ATCOR MetaLayer.2. Click Define Haze and Cloud.

Automatically creating a mask

1. Click Automatically Calculate Haze and Cloud.2. Under Mask Size, click either:

• Large area haze mask to create a mask overall the areas that may contain haze. Thisoption also includes areas where haze issuspected, but may not be obvious uponvisual inspection.

• Smaller area haze mask to create a maskonly over the areas where the haze is obvious.

3. Under Haze Thickness, click either:• Correct thin haze to thick haze if you want to

include the thick haze (cloud cover) when youperform the correction.

• Correct thin to medium haze if you want toignore the thick haze (cloud cover) when youperform the correction.

4. In the Water Refl. Threshold in NIR (%) box, typethe value in percent representing the limit belowwhich is considered water reflectance values in theNIR sensor band.

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5. In the Water Refl. Threshold in Snow (1.6um) (%)box, type the value in percent representing the limitbelow which is considered water reflectance valuesin the 1.6 um sensor band.

6. In the Cloud Refl. Threshold in Blue (<0.8um) (%)box, type the value in percent representing the limitbelow which is considered cloud reflectance values.

7. Under Output, click either:• Display to show the mask in the Focus view

pane.• Save to save the mask layer in a file. In the

File list, click the file where you want to savethe mask or click Browse to select the file. Inthe Haze Layer list, click the layer where youwant to save the haze mask. In the CloudLayer list, click the layer where you want tosave the cloud mask.

8. Click Create Mask.

Importing the masks from a file

1. Click Load Haze and/or Cloud from File.2. Under Haze, in the File list click the file that

contains the haze mask or click Browse to selectthe file. In the Layer list, click the layer containingthe haze mask.

3. Under Cloud, in the File list click the file thatcontains the cloud mask or click Browse to selectthe file. In the Layer list, click the layer containingthe cloud mask.

4. Click Create Mask.

Editing the Cloud mask

1. Right-click the ATCOR MetaLayer.2. Click Edit Cloud Mask.3. Use the New Shapes tools to modify the bitmap.

For more information, see Adding points to anactive layer on page 303 .

Editing the Haze mask

1. Right-click the ATCOR MetaLayer.2. Click Edit Haze Mask.3. Use the New Shapes tools to modify the bitmap.

For more information, see Adding points to anactive layer on page 303 .

Editing the Visibility layer

1. Right-click the ATCOR MetaLayer.2. Click Edit Visibility.3. Use the New Shapes tools to modify the bitmap.

For more information, see Adding points to anactive layer on page 303 .

Opening the Run AtmosphericCorrection dialog box

When you perform the atmospheric correction, Focusadds a thematic raster metalayer to the Maps tree. Themetalayer contains the image being corrected, the Hazebitmap mask layer, the Cloud bitmap mask layer, thevisibility layer, and a layer with the Value-Added Data.

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To use the Spatially Varying Conditions option, you musthave the Red, near-infrared (NIR), and Short WavelengthInfrared (SWIR) bands, and you must have referenceareas of known reflectance such as a section of densevegetation or a body of water present outside the haze touse as a reference target. When you use the SpatiallyVarying Conditions option, Focus calculates the visibilityfor each pixel in the image using the value set in theVisibility box on the Atmospheric Correction Configurationdialog box as a starting point for the calculation.

Use the Constant Conditions option when you aremissing one of the bands, the image does not contain areference target, or you are sure that the imagerepresents an area with constant atmospheric conditionssuch as an area without rugged terrain, large bodies ofwater, or mountains. When you use the ConstantConditions option, Focus uses the value set in theVisibility box on the Atmospheric Correction Configurationdialog box as the visibility for each pixel in the image.

The result of the atmospheric correction is a scaledsurface reflectance image with a range of 0 to 255 for8-bit data and 0 to 65535 for 16-bit data. If you wantunscaled values or percent reflectance values, divide thescaled values by 4 for 8-bit data and by 10 for 16-bit data.For example, 150 divided by 10 equals 15% reflectancefor a 16-bit image.

1. In the Maps tree, right-click the ATCOR MetaLayer.2. Click Run Atmospheric Correction.

Running the correction

1. Click Constant Conditions if you want to performthe correction assuming relatively uniformatmospheric conditions over the image.

2. Click Spatially Varying Conditions if you want toperform the correction assuming differingatmospheric conditions throughout the image.

3. Under Corrected Output, in the File box click thefile where you want to save the corrected data orclick Browse to select a file.

Deriving additional data from the correctedimagery

1. Under Value-added Data Output, in the File boxclick the file where you want to save the additionaldata or click Browse to select a file.

2. To perform a transformation that minimizes theinfluence of soil brightness, select the SoilAdjusted Vegetation Index check box.

3. To calculate the green leaf density, select the LeafArea Index check box.

If you want to change the equation used for the LAIcalculation, click LAI Options. For moreinformation, see Opening the Leaf Area IndexModel dialog box on page 296 .

4. To calculate the calculate the amount ofphotosynthetically active radiation absorbed by aplant canopy, select the Fraction of AbsorbedRadiation check box.

If you want to change the values used in the FPARcalculation, click FPAR Options. For moreinformation, see Changing the values for the

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fraction of photosynthetically active radiation(FPAR) equation on page 297 .

5. To calculate ground reflectance, select the SurfaceAlbedo check box.

6. To calculate the difference between the emittedatmospheric radiation and the emitted surfaceradiation, select the Thermal Flux Differencecheck box.

7. To calculate the exchange rate of energy betweenthe earth#s surface and the underground, select theGround Heat Flux check box.

8. To calculate the shortwave solar radiation absorbedby the surface, select the Absorbed SolarRadiation check box.

9. To calculate the exchange rate of stored heatenergy between the air and the earth#s surface,select the Latent Heat check box. Latent heat fluxis measures the amount of energy needed tochange matter from one state to another (from solidto liquid to gas).

10. To calculate the exchange rate of excess heatenergy between the air and the earth#s surface,select the Sensible Heat check box. Sensible heatflux measures the amount of energy needed tochange air temperature.

11. To calculate the difference between absorbed andemitted shortwave and longwave radiations, selectthe Net Radiation check box.

12. Click Run Correction.

Opening the Leaf Area Index Modeldialog box

The leaf area index (LAI) is the density of the greenleaves in an area. It is a measure of the green leaf area(one-side) per unit of surface area.

You can choose one of two equations to calculate thedensity: the Soil Adjusted Vegetation Index or theNormalized Difference Vegetation Index. Both equationscontain three parameters whose values depend on thetype of vegetation being measured and on the season inwhich they are being measured.

The LAI can only approximate typical trends in thevegetation. It should not be used to replace or confirmfield measurements of other types of vegetation indifferent seasons. The defaults provided for the equationsare typical for soybean crops (Choudury et al. 1994). Byusing a constant set of values, either custom or default,to calculate the LAI for images of the same area overtime, you can uncover trends in the vegetation.

SAVI uses the red and near-infrared bands to measurethe density and vigor of green vegetation by attempting toeliminate the reflectivity of the ground beneath thecanopy.

NDVI uses the visible and near-infrared bands tomeasure the density and vigor of green vegetation bycomparing the amount of visible light reflected to theamount of near-infrared light reflected.

1. Open the Run Atmospheric Correction dialogbox, see Opening the Run Atmospheric Correctiondialog box on page 294 .

2. Under Value-Added Data Output, select the Leaf

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Area Index check box.3. Click the LAI Options button.

Selecting the equation for calculating theLeaf Area Index

1. Select one of the following:• SAVI for the Soil Adjusted Vegetation Index

equation.• NDVI for the Normalized Difference Vegetation

Index equation.

Changing the values for the fractionof photosynthetically active radiation(FPAR) equation

The Fraction of Photosynthetically Active Radiation(FPAR) equation uses the red and near-infrared bands tocalculate the fraction of radiation between 400 and 700nm absorbed by green vegetation.

The FPAR equation contains three parameters whosevalues depend on the type of vegetation being measuredand on the season in which they are being measured.The equation also includes the result from the leaf areaindex (LAI) equation that you selected (see Opening theLeaf Area Index Model dialog box on page 296 ).

The FPAR equation can only approximate typical trendsin the vegetation. It should not be used to replace orconfirm field measurements of other types of vegetation

in different seasons. The defaults provided for theequations are typical values based on several studies(Asrar et al. 1984, Asrar 1989, Wiegand et al, 1990,1991). By using a constant set of values, either custom ordefault, to calculate the FPAR for images of the samearea over time, you can uncover trends in the vegetation.

1. Open the Run Atmospheric Correction dialogbox, see Opening the Run Atmospheric Correctiondialog box on page 294 .

2. Under Value-Added Data Output, select theFraction of Absorbed Radiation check box.

3. Click the FPAR Options button.

Opening the Advanced Option dialogbox

The Advanced Options are parameters used in producingthe data in the Value-Added Data Output section on theRun Atmospheric Correction dialog box. The availabilityof the parameters depends on the presence or absenceof data:

• The Visibility data, BRDF Correction, and TerrainReflectance sections are only available in ATCOR3.

• The Emissivity and Radiation and heat flux sectionsare only available if your data includes a thermalband.

• The Reference pixels section is only available ifyour data does not include a Short WavelengthInfrared (SWIR) band. If your data does includeone, Focus automatically calculates the referencepixels.

1. In the Maps tree, right-click the ATCOR MetaLayer.

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2. Click Advanced Options.

Setting the parameters

1. Under Visibility data, click Calculate to calculatethe visibility values when you perform theatmospheric correction or click Use Existing toselect a visibility layer calculated previously.

If you selected Use Existing, in the File list click thefile that contains the visibility layer or click Browseto select a file. In the Layer list, click the layercontaining visibility values.

2. (Available only if your data includes a thermal band)Under Emissivity, click Constant to use 0.98 asthe emissivity constant for all the pixels in the imageor click Surface cover dependant to calculate theemissivity for each pixel using specific valuesdepending on whether the pixel represents water,vegetation, or another material.

3. (Available for ATCOR2 only and only if your dataincludes a thermal band) In the Scene airtemperature box, type the overall temperaturepresent in the area at the time the image was taken.Select the temperature scale used to measure theair temperature.

4. (Available for ATCOR3 only and only if your dataincludes a thermal band) In the Air temperaturebox, type the temperature of the air at a specifiedelevation. Select the temperature scale used tomeasure the air temperature. In the Elevation box,type the elevation at which the air temperature wasmeasured.

5. (Available for ATCOR3 only and only if your data

includes a thermal band) In the Temperaturegradient box, type a value representing the numberof degrees Celsius at which the temperature willchange per 100 meters of elevation.

6. (Available for ATCOR3 only and only if your dataincludes a thermal band) In the Water vapor partialpressure box, type a value representing the rate atwhich the pressure will change per 100 meters ofelevation.

7. In Threshold T1 box, type the value representingthe limit below which is considered bare soil or othernongreen materials. For more information, seeSetting the thresholds for the reference pixels onpage 299 .

8. In Threshold T2 box, type the value representingthe limit below which is considered high NIRreflectance. For more information, see Setting thethresholds for the reference pixels on page 299 .

9. In the Reflectance % in RED band box, type thevalue in percent representing the limit below whichis considered vegetation. For more information, seeSetting the thresholds for the reference pixels onpage 299 .

10. (Available for ATCOR3 only) Under BRDFCorrection, click Empirical Correction if you wantto correct view and illumination angle effects or clickNo Correction if you do not.

To specify which empirical correction function youwant to use, click BRDF Options. For moreinformation about the Bidirectional ReflectanceDistribution Function (BRDF), see Opening theEmpirical BRDF Correction dialog box on page 299 .

11. (Available for ATCOR3 only) Under TerrainReflectance, you select the method that you want

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to use to calculate the terrain reflectance for eachpixel, which is used to calculate the adjacencycorrection and the spherical albedo effect. You canclick either:

3 iterations to calculate the average terrainreflectance. The equation is computed iterativelywith the terrain view factor and sky view factorcalculated from the digital elevation model (DEM) toachieve convergence.

No iterations to calculate the terrain reflectancewithout iterative calculations to improve theaccuracy.

12. Click OK.

Setting the thresholds for thereference pixels

If the data contains a Short Wavelength Infrared (SWIR)1.6 m or 2.2 m band, Focus automatically calculates thereference pixels when you run the atmospheric correctionusing the Spatially Varying Conditions option.

Reference pixels are target areas of known reflectance inone band present outside the haze. In Focus the targetareas are areas of dense, dark vegetation. The referencepixels are used to develop a spatial map of the visibility(optical depth) of the pixels in the image.

Threshold T1 identifies areas with dense vegetation bycalculating the Ratio Vegetation Index using both the redand near-infrared sensor (NIR) bands. The thresholdmarks the value representing the limit below which is

considered bare soil or other nongreen materials.

Threshold T2 identifies pixels with low reflectance in theNIR band. The threshold marks the value representingthe limit below which is considered materials with highreflectance. It is used to exclude vegetation with highreflectance, therefore identifying dark vegetation.

Reflectance % in RED band identifies the value inpercent representing the limit below which is consideredvegetation. The reflectance values for dark vegetation aretypically between 1 to 3% in the RED band. Dr. Richterrecommends that you begin with a value of 2% andcompare the result to the original image to determine ifthe identified targets are acceptable reference pixels.

• See Opening the Advanced Option dialog box onpage 297 .

Opening the Empirical BRDFCorrection dialog box

Bidirectional Reflectance Distribution Function (BRDF),available only in ATCOR3, corrects the reflectanceeffects resulting from the view angle and illuminationangle when the image is taken. The reflectance canappear very different depending on the position of thesensor and the position of the light source. The textureand composition of the surface also affect reflectance.

BRDF compensates for these effects by computing afactor (G) used to reduce the reflectance of pixels with

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extreme incident angles so that they more closelyresemble the reflectance values of pixels with moderateincident angles. In the BRDF equation:

• t represents the threshold angle• i represents the incidence angle• e represents the exitance angle (for sensors with

the tilt capability)

The lower boundary value (g) is a value less than 1 thatconstrains the factor G to prevent over-reducing thereflectance of pixels with extreme incident angles:

. By default the lower boundary value is

0.25. If the corrected reflectance values appear too low(dark), decrease the lower boundary value and repeat thecorrection.

1. Open the Advanced Options dialog box, seeOpening the Advanced Option dialog box on page297 .

2. Under BRDF Correction, click EmpiricalCorrection.

3. Click the BRDF Options button.

Selecting the BRDF equation

1. Select one of the following. Click:• (1) G = cos(i)/cos(t) when the incidence angle

is between 60 to 90 degrees. This equation isrecommended for most cases.

• (2) G = sqrt[cos(i)/cos(t)] when the incidenceangle is between 60 to 90 degrees.

• (3) G = cos(i)*cos(e)/cos(t) when the sensorwas tilted when the image was taken resulting

in a larger off-nadir viewing angle, 20 to 30degrees for example.

• (4) G = sqrt[cos(i)*cos(e)/cos(t)] the sensorwas tilted when the image was taken resultingin a larger off-nadir viewing angle, 20 to 30degrees for example.

2. In the Threshold angle box, type the value thatresults from adding 20 degrees to the solar zenithvalue.

3. In the Lower boundry box, type a value to raise orlower the boundary.

4. Click OK.

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Chapter 8Understanding vector layer typesVectors are a way of presenting spatial information.Instead of representing that information in pixels, vectorsrepresent the information as points, lines, and polygons.Focus provides two main methods for presenting thevectors: Unstructured and Topological. Each methodcontains several vector layer types.

Vector layers contain a number of default attributes thatcan be viewed with the Attribute Manager. For moreinformation, see Understanding vector layer type defaultfields on page 307 .

Unstructured vector layersAn unstructured layer can contain a combination ofshapes. You can limit the layer to a particular type. Thefollowing describes the shapes available on anunstructured layer.

Point:

A shape that contains only one vertex.

Line:

A shape that contains two or more vertices, where thefirst and last vertices do not conjoin.

Whole Polygon:

A shape that contains three or more vertices, where thefirst and last vertices conjoin.

Unconnected Table:

A layer that contains attributes but is not associated to ageographical component. (See Creating an unconnectedtable on page 306 )

About topological layersTopology is a mathematical representation of the surfacefeatures of a location. Topology involves not only buildinga relationship between the shape and the attributes, butalso a relationship between the shapes themselves.

Topological Line:

Contains lines that use topological conventions. Atopological line can contain several vertices, but only twonodes. A node is the start point or the end point of a line.

A topological line layer is composed of two layers. Onelayer stores the lines and the other stores the nodes.Focus generates and manipulates nodes in the nodelayer as you edit and create the topological lines.

Understanding topological lines

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Topological Polygon

Contains polygons that use topological conventions. Atopological polygon is a closed figure formed by one ormore topological lines that define the boundary of aspecific location.

When a topological polygon overlaps another, theintersecting points become nodes; the lines are split,resulting in a new polygon in the overlap. That is, twotopological polygons become three.

A topological polygon layer is composed of three layers.When you create a topological polygon layer, Focus alsogenerates a line layer and a node layer. As you createand edit polygons, Focus manipulates the lines andnodes that form the polygon.

The line layer includes attributes that identify whichpolygons lie on either side of each line. The regionoutside the boundary of the digitized areas on the layerare represented by a global polygon. This global polygon,called Outside Area, appears as -1 in the Attribute Tablefor topological line layers. These attributes describe therelationship between the shapes.

Understanding topological polygons

Thematic rastersA thematic raster is a raster with associated attributes.Normally, rasters present spatial information as pixelvalues. The numeric value of the pixel represents theattribute for that pixel. Neighboring pixels with the samepixel value collectively represent a surface feature. Inthematic rasters, the pixel values are associated to anynumber of attributes, which can be viewed using theAttribute Manager. In Focus, the attributes for a thematicraster are stored in a vector segment in its file.

Understanding vector editing in amath model areaA Math Model Area is similar to an Area, except theprojection is determined by a math model segmentcontained in the image file. The image is displayed

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without correction in the viewer, but accurate groundcoordinates are calculated for each pixel using the pixeland line coordinates, the math model, and the digitalelevation model (DEM) or an approximate elevation valuethat you provide. For more information, see Using a mathmodel with images on page 40 .

In the Math Model Area, you can digitize geocodedthree-dimensional vectors on a raw image, instead ofgoing through the potentially time-consuming,labor-intensive process of orthorectifying the imagery.Vectors are saved in the projection of the layer withoutthe effects of the math model. As such, the vectors haveaccurate X, Y, and Z coordinates.

You can open vectors digitized in the Math Model Area inan Area containing an orthorectified or geometricallycorrected image and the vectors will display correctly.However, if you open vectors without elevation in a MathModel Area, the vectors may be offset from the correctposition, as it uses elevation values to calculate thecorrect position.

When you edit vectors in a Math Model Area, you areessentially moving objects in three-dimensional spaceusing two-dimensional vision. You cannot modify the Xand Y coordinates of the vector without affecting the Zcoordinate. To edit only the X and Y vector coordinates,open the vectors in a planimetric layer instead.

Adding a new vector layer

1. In the Maps tree, right-click an Area and click NewVector Layer.

2. In the New Vector Layer dialog box, enable thetype of layer that you want in the Layer Type area.For more information about layer types, seeUnderstanding vector layer types on page 301 .

3. In the Georeferencing area, enable one of thefollowing options:

• Use Area Georeferencing: uses the samegeoreferencing as defined in the New Area.

• Use Layer Georeferencing: uses the samegeoreferencing as defined in an existing layer.Choose a layer that has the desiredgeoreferencing form the list box.

• User-entered: defines the georeferencing.Enter the projection , bounds, and extents asrequired.

4. Click OK.

Adding points to an active layer

1. On the Editing toolbar, click the New Shapes arrowand choose Points.

2. Click in the view pane where you want to add apoint.

3. Repeat step 2 for all points that you want digitized.

Adding a line or a polygon to anactive layer

1. On the Editing toolbar, click the New Shapes arrowand choose Line or Polygon.

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2. Click in the view pane where you want to add thefirst point of the line or polygon.

3. Repeat step 2 until you have digitized the shapethat you want.

4. Double-click the last vertex to complete the shape.

Adding a rectangle or ellipse to anactive layer

1. On the Editing toolbar, click the New Shapes arrowand choose Rectangle or Ellipse.

2. Click in the view pane where you want to add arectangle or ellipse.

For a rectangle, start at a corner of the area whereyou want to draw a rectangle; for an ellipse, start inthe center of the area.

3. Drag to form a shape.

If you want to create a square or a circle, press andhold the Shift key while dragging.

Tracing a line on an active layer

1. On the Editing toolbar, click the New Shapes arrowand choose Trace.

2. Click in the view pane where you want to starttracing.

3. Trace over the line.4. Double-click to complete the trace.

Digitizing 3-D vectors

Using the mono-restitution process, you can digitizevectors with accurate X, Y, and Z coordinates with theNew Shapes tools. To set up mono-restitution, you needa raw image with a math model segment and a digitalelevation model (DEM), or an estimate of the elevation.

The math model and DEM are used to set thegeoreferencing for the Math Model Area, in which theimage is displayed without correction in the viewer.Accurate ground coordinates are calculated for each pixelusing the pixel and line coordinates, the math model, andthe DEM or approximate elevation value. For moreinformation, see Using a math model with images onpage 40 and Understanding vector editing in a mathmodel area on page 302 .

1. In the Focus window, open a raw image with a mathmodel segment. Click Math Model.

2. Set up the Math Model Area (see Using the mathmodel for georeferencing on page 41 ).

3. Use the New Shapes tools on the Editing toolbar todigitize vectors (see Adding points to an active layeron page 303 ).

Performing tasks in the AttributeManagerThe Attribute Manager is another way of visualizing data.Each record in the Attribute Manager represents a shapeon the layer. Each shape is described by a number ofattributes. You can view the records individually or in atable. In the table, each row records all attributes for ashape. Each column holds values for an attribute.

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See:

Viewing records on page 307

Selecting and clearing records and fields on page 307

Understanding vector layer type default fields on page 307

Adding records to the Attribute Manager on page 309

Adding new fields on page 309

Setting the field definitions on page 309

Changing an existing field to a geometry field on page 310

Updating the geometry on page 311

Using find and replace in the Attribute Manager on page 311

Selecting all records that match a value in the current cellon page 312

Using the compute function on page 314

Creating a relational database on page 312

Opening the Aggregate Attributes dialog box on page 315

Opening the Area Neighbors dialog box on page 315

Opening the Z-value Transfer dialog box on page 317

Exporting layer attributes to a file on page 318

About the Preferences dialog boxThe Preferences dialog box contains options that controlthe cursor#s behavior in the Attribute Manager andcontrols what statistics are displayed in the AttributeManager.

Select the topic that interests you:

Controlling the Attribute Manager cursor on page 305

Setting a selected record statistics display on page 306

Controlling the Attribute Managercursor

You can control the cursor movement and behavior in theAttribute Manager through the Attribute ManagerPreferences dialog box.

1. In the Attribute Manager, click Edit and then clickPreferences.

2. In the Preferences dialog box, choose one of thefollowing options from the After pressing #Enter#list box:

• Moves To Next Record: moves the cursorfrom record to record as you press Enter

• Moves To Next Field: moves the cursor fromfield to field as you press Enter

• Does Not Move: keeps the cursor in a cellwhen you press Enter

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3. Choose one of the following options from the Whenentering cell list box:

• Select Entire Cell: highlights the contents ofthe cell

• Go To Start Of Cell: places the cursor beforethe contents in a cell

• Go To End Of Cell: places the cursor after thecontents in a cell

4. Click OK.

Setting a selected record statisticsdisplay

When you select a record, its statistics are displayed inthe Attribute Manager. You can choose the statistics youwant to display.

1. In the Attribute Manager, click Edit and then clickPreferences.

2. In the Preferences dialog box, enable any of thefollowing check boxes in the Field Statistics area:

• Count: displays the number of selectedrecords

• Sum: calculates the sum of the values for theselected records for each numeric field

• Mode: calculates the value that occurs themost frequently among the selected recordsfor each field

• Mean: calculates the average value of theselected records for each numeric field. Theaverage is obtained by adding values of theselected records and dividing that value by thenumber of records used in the sum.

• Minimum: displays the lowest value in the

numeric field from the selected records• Median: ranks for each numeric field the

values of the selected records in numericalorder. The median is the middle value of theselected records.

• Maximum: displays the highest value in thefield from the selected records

• Standard Deviation: measures the variationin the distribution of values, which is calculatedfrom square root of the variance

3. Click OK.

Creating an unconnected table

An unconnected table is a layer that contains attributesthat are not directly associated to a vector representing ageographical location.

1. Create an unstructured layer. For more information,see Adding a new vector layer on page 303 .

2. Right-click the layer and click Attribute Manager.3. Design the table as you require. (See Adding new

fields on page 309 )4. From the Record menu, click Add New.5. Enter data.

Restricting the layer so you cannotadd shapes to it

1. In the Focus window, save the layer.2. Click the Files tab.3. Right-click the layer and click Properties.4. In the File Properties dialog box, click the

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MetaData tab.5. Click the Add button.6. In the Value column next to LAYER_TYPE, type

TABLE in upper case letters.7. Click OK.

Viewing records

When you view individual records, the fields appear in thefirst column followed by the values for that record.

When you view all records in a table, each row is arecord that contains all the attributes for the shape. Eachcolumn is a field that contains the values for eachattribute.

To view an individual record

• From the View menu in the Attribute Manager, clickRecord Display.

To view a record in a table

• From the View menu in the Attribute Manager, clickTable Display.

Opening a file saved as an attribute

If a file name and a path are saved as an attribute, youcan open the file from the Attribute Manager.

1. In the Attribute Manager, click the cell containingthe file name and path of the file that you want to

open.2. From the View menu in the Attribute Manager, click

File.

The file will open using the operating system'sdefault application for that file type.

Selecting and clearing records andfields

To select a record, click the lead cell next to it. You canpress and hold Shift and click a range of records orfields, or press and hold Ctrl and click multiple records orfields. Statistics for selected records display at the bottomof the Attribute Manager. The lead cell in the currentrecord is highlighted in yellow.

To select a field, click the heading of the field. Theheading in the current field is highlighted in yellow.

• On the Attribute Manager toolbar, click the Clearselected records or Clear selected fields button.

Understanding vector layer typedefault fields

When you create a new vector layer, it automaticallycontains a set of default fields that Focus maintains. Youcan modify definitions of some default fields; however,most are restricted by the system. (See Setting the fielddefinitions on page 309 ) The following table lists the fieldsmaintained by Focus.

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Table 20. Default Fields

Field Name Description Layer Type

REPCode

Contains the keyto define theappearance ofthe shapesaccording to theRepresentationEditor. (SeeUsing the GPStool on page 351 )

Unstructured

Angle

Controls the slantof the text stringor point.Measured inradians bydefault, but youcan change it todisplay indegrees,gradians, or mils.

PointUnstructured

TextString

Defines the fieldto acceptcharacters, suchas text. You cantype directly onthe layer or in theTextString field.

PointUnstructured

GroupID

Identifies a set ofshapes that yougroupedtogether. (See

Point LineUnstructuredWhole Polygon

Field Name Description Layer Type

Grouping shapeson page 321 ) Theidentificationnumber isgenerated byFocus andcannot bechanged.

Area

Displays thecomputed areaenclosed by thepolygon.

Whole PolygonTopologicalPolygon

Perimeter

Displays thecomputedcircumference ofthe polygon.

Whole PolygonTopologicalPolygon

ArcIdList

Identifies thelines thatcompose apolygon in atopological layer.(See Abouttopological layerson page 301 )

TopologicalPolygon

RightAreaId

Identifies thepolygon on atopological layerwhich is on theright of the line.(See Abouttopological layerson page 301 )

Topological Line

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Field Name Description Layer Type

LeftAreaId

Identifies thepolygon on atopological layerwhich is on theleft of the line.(See Abouttopological layerson page 301 )

Topological Line

StartNodeId

Identifies thepoint (node) thatbegins atopological line.(See Abouttopological layerson page 301 )

Topological Line

EndNodeId

Identifies thepoint (node) thatends atopological line.(See Abouttopological layerson page 301 )

Topological Line

Length

Displays thecomputeddistance coveredby the line.

Line TopologicalLine

• From the Field menu in the Attribute Manager, clickShow All.

Adding records to the AttributeManager

As you add shapes in the view pane, a record isautomatically created in the Attribute Manager. Eachrecord contains the default fields or the fields that wereset when the table was created. You can add a record tothe table not associated with a shape. (See Creating anunconnected table on page 306 )

1. From the Maps tree, right-click a layer and clickAttribute Manager.

2. From the Record menu in the Attribute Manager,click Add New.

Adding new fields

Records in the Attribute Manager contain default fieldsand fields that were set when the table was created. Youcan add new fields or modify the existing ones. To modifythe fields, see Setting the field definitions on page 309 Youcan also add new fields directly from the TableDefinitions dialog box.

1. From the Maps tree, right-click a layer and clickAttribute Manager.

2. From the Field menu in the Attribute Manager, clickAdd New.

For information on how to modify the fields, seeSetting the field definitions on page 309 .

Setting the field definitions

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You can define the contents of the Attribute Managertable by choosing attributes in the table and by adding orremoving records using the Table Definition dialog box.You can also set the field properties for new and existingrecords.

1. From the Edit menu in the Attribute Manager, clickTable Definition.

2. In the Table Definition dialog box, do any of thefollowing:

• To hide a field, disable the appropriate checkbox in the Shown column.

• To change a field name, double-click the fieldin the Name column and type a new name.

• To add a field, click the Add button.• To remove a field, select it and click the

Remove button.3. Type or choose data that will appear by default from

the Default Value list box.4. Type a value that will appear in fields that do not

contain real data from the NoData Value list box.

NoData values are not included in computations.

5. Choose one of the following options from the Readonly list box:

• No: lets you change values in a field• Yes: restricts changes to a field

6. Choose how you want to align data in a field fromthe Justification list box.

7. Type or choose the width of a field in characters inthe Field size list box.

8. Type or choose a number of decimal placesdisplayed in a field in the Decimal places list box.

9. Choose one of the following options from theScientific notation list box:

• Yes: displays values in a field as scientificnotations

• No: displays values in a field as regularnumbers

• Auto: displays values as either regularnumbers or scientific notations, depending onwhich is shorter

10. Choose one of the following unit types for a fieldfrom the Angular units list box:

• Radians: expresses angles in radians, where2 pi radians equals the 360 degrees in a circle(one radian equals approximately57.29577951 degrees)

• Degrees: expresses angles in degrees, whichis the angle between two adjacent radiimeasured at the center of the circle tht isdivided along its radius into 360 equal parts

• Mils: expresses angles in mils, which measureangles where 1 mil equals 1/6,400 of a circle(1 mil equals approximately 0.05625 degrees)

• Grads: expresses angles in grads, whichmeasure angles where 400 grads equals the360 degrees in a circle (a 90-degree rightangle equals 100 grads)

11. Choose a conversion type from the Conversion listbox.

If you choose New, type a factor in the ConversionFactor box.

12. Click OK.

Changing an existing field to a

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geometry field

Geometry fields are system fields that display themeasurements of lines or polygons on a layer. Focusautomatically calculates and updates thesemeasurements as you modify the respective shapes.Three Geometry Field types are available:

• Length: calculates the length of a line• Perimeter: calculates the circumference of a

polygon• Area: calculates the area of a polygon

When you create a new vector layer, Focus automaticallycreates Length, Area, and/or Perimeter fields in theAttribute Manager according to the selected layer type.You can modify some properties, but most remainunavailable.

1. From the Edit menu in the Attribute Manager, clickTable Definition.

2. In the Table Definition dialog box, enable thecheck box in the System column for the field thatyou want to change into a Geometry Field.

3. In the Geometry Field Properties area, choose thetype of field that you want from the Type list box.

4. Choose a unit of measurement for the field from theDisplay units list box.

5. Click OK.

Adding all appropriate geometryfields

1. From the Edit menu in the Attribute Manager, clickTable Definition.

2. In the Geometry Field Properties area, clickCreate.

3. Select each new field and define as necessaryusing the available properties. (See Setting the fielddefinitions on page 309 )

Updating the geometry

If you edit a layer outside of Focus, the Geometry Fieldsmay no longer be up-to-date when you reopen them inFocus.

1. From the Maps tree, right-click a layer and clickAttribute Manager.

2. From the Field menu in the Attribute Manager, clickUpdate Geometry.

Using find and replace in the AttributeManager

1. From the Edit menu of the Attribute Manager, clickFind or Replace.

2. In the Find and Replace dialog box, type thecharacters that you want to find in the Find whatbox.

3. Enable any of the following check boxes:• Match case: searches for the examples with

the same capitalization as the characters inthe Find what box only

• Match entire cell: searches for the examplesthat contain only the characters in the Find

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what box. For example, if you type 123 in theFind what box, you will only receive matchesfor cells that contain only 123. You will notreceive matches for other numbers such as12345 or 9123.

• Limit search to selected fields: searchesonly in a field selected in the AttributeManager

• Limit search to selected records: searchesonly in a record selected in the AttributeManager

4. Click Find next.5. If you want to replace text, click the Replace tab

and type the characters that you want to use as thereplacement in the Replace with box.

6. Click Replace.

If you want to replace all the examples with thereplacement characters, click Replace all.

Creating a relational database

You can join layers to form a relational database. Onelayer serves as the source of the data. This layer, calledthe Secondary Table, usually contains an UnconnectedTable (See Creating an unconnected table on page 306 ),but you can also use another layer in your project as thesource. The layer that receives the attributes from theSecondary Table is called the Primary Table.

When you join layers, you select one field in PrimaryTable and a corresponding field in the Secondary Tableto serve as the key. The key is the common link betweenthe layers. The attributes from the Secondary Table

appear in the Primary Table.

The Secondary Table acts like a look-up table for theattributes. If you change the values in the SecondaryTable, the Primary Table is automatically updated withthe new values, as long as the tables are joined.

1. Right-click the layer that you want to use as thePrimary Table and click Attribute Manager.

2. From the Tools menu in the Attribute Manager,click Table Join.

3. In the Define Table Join dialog box, click Browse.4. In the Select Layer dialog box, choose the layer

that you want to use as the Secondary Table.5. In the Primary Table#s Attribute box, select an

attribute.6. Select the attribute from the Secondary Table#s

Attributes box that you want to join with theattribute from the Primary Table#s Attribute box.

7. Click the Add button.8. Click OK.

Selecting all records that match avalue in the current cell

A query searches and selects records that correspond toa set of criteria that you define.

Match Current Cell:

All records that contain the same value as the current cellare selected. The statistics of the selected recordsdisplay at the bottom of the Attribute Manager. (SeeSetting a selected record statistics display on page 306 )

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1. Select a value that you want to match.2. From the Record menu in the Attribute Manager,

click Query by and then click Current.

Exclude Current Cell:

All records that do not contain the same value as thecurrent cell are selected. The statistics of a selectedrecord is displayed at the bottom of the AttributeManager. (See Setting a selected record statistics displayon page 306 )

Selecting all records that do notmatch a value in a selected field

1. Select a value that you want to exclude from thesearch.

2. From the Record menu in the Attribute Manager,click Query by and then click Excluding Current.

Query by Example:

You can create an expression that selects allcorresponding records. An expression can be astatement where two attributes are connected by arelational operator to produce a result. It can also be twoor more statements joined by an AND or OR operator.

For example, if you have an attribute called Length thatdescribes the length of rivers on a layer, you can query'Length > 10.# The result shows all records that contain avalue greater than 10 in the Length field.

Making a query by example

1. From the Record menu in the Attribute Manager,click Query by and then click Example.

2. In Query by Example dialog box, choose New fromthe Equation list box.

3. In the Attributes list, select the attribute you want touse in the query.

4. Select a relational operator (such as =, >, <, and soon) from the list box next to the Attributes list.

5. Enable one of the following options:

Attribute Values: uses field values in the query

Attributes: uses another attribute in the query

6. Select a value or attribute from the appropriate list.7. Enable one of the following options:

• AND: selects records that are true for bothjoined statements

• OR: selects records that are true for at leastone of the joined statements

8. Click Add.9. Repeat step 3 to step 8 as needed.

10. Click Save.11. Enter a name for the equation in the Equation

name box and click OK.12. In the Query by Example dialog box, click OK.

Query by Subset

If you select Query by Subset before using the Query byfeatures (Current, Excluding Current, and Example), the

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query is limited to the selected records only instead ofperforming the query on all the records.

Limiting the query to selected records

1. Select records in the Attribute Manager.2. From the Edit menu in the Attribute Manager, click

Query By Subset.3. Perform a query.

Using the compute function

Compute creates a field containing the results of anequation or expression involving the attributes in a layer.You can build equations using the calculator or you cancreate more complex expressions with the AdvancedCompute features and EASI scripts. For more informationabout EASI scripts, see the EASI User Guide.

When you build an expression, either type the expressionin the Expression box or build the expression by clickingthe buttons and items in the dialog box. Combining thetwo methods may cause unwanted effects.

1. From the Field menu in the Attribute Manager, clickCompute.

2. From the View menu in the Compute dialog box,click one of the following options:

• Basic: creates an equation using the attributesand the calculator

• Advanced: creates an expression using theattributes, the calculator, and functions

3. Build an expression. You can use any combination

of the following to create the expression that youwant:

• Type all or part of the expression in theExpression box. Text should be placed indouble quotes (for example, #text#).

• Double-click an attribute in the Attributes listto add it to the expression.

• Use the calculator to include integers and thebasic mathematic operators in the expression.

• Select a category of functions from theCategories list box to display the availablefunctions in that category. In the Functionslist, select the function that you want to use inthe expression. (Available only on theAdvanced Compute)

4. If you want to display the result on the screenwithout adding it to the Attribute Manager, enablethe Single Value check box and proceed to step 8.

5. If you want to include the result in the AttributeManager, select a field in the Field Name box thatwill receive the results of the computation or typethe name of a new field.

6. In the Field Description box, type a description ofthe contents of the field.

7. Choose one of the following types of field from theField Type list:

• Text: defines the field as a text string• Integer: defines the field for positive or

negative whole numbers• Float: defines the field for single-precision real

numbers• Double: defines the field for double-precision

real numbers8. Click the Run button.

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If you want to save the equation with the layer, clickSave.

Opening the Aggregate Attributesdialog box

The Aggregate Attributes dialog box is used as areporting tool or to quickly recombine data for analysis. Itcombines records based on selected attributes. Theoutput is an unconnected table that contains the resultsof a specified function or statistical calculation.

The Based On criteria is comparable to the Group Byclause in an SQL select statement.

• From the Tools menu in the Attribute Manager,click Aggregate Attributes.

• From the Layer menu in the Focus main menu,click Aggregate Attributes.

Performing a calculation

1. In the Aggregate Attributes dialog box, do any ofthe following:

• To use only the selected records in theoperation, enable the Aggregate selectedshapes only check box.

• To compute the results based on the shapesthat contain the same style in theRepresentation Editor, enable theRepresentation values option and select anattribute and function that you want to use.

• To compute the results based on the recordsthat contain the same attribute values, enablethe Attributes option and enable the chck boxnext to the attribute in the Based On column.Add any function or statistic fields to the outputAttribute Manager. For more information, seeAdding function fields to output layers on page 320.

• To add a field containing the number ofrecords used in the calculation, enable theAdd a count field check box.

2. Click Aggregate.

Opening the Area Neighbors dialogbox

Area Neighbors is a reporting tool for whole polygonlayers, topological polygon layers, and thematic rasters. Itgenerates an unconnected table containing attributes thatyou can analyse.

1. From the Tools menu in the Attribute Manager,click Area Neighbors.

2. From the Layer menu in the Focus main menu,click Area Neighbors.

Reporting bordering areas

1. In the Area Neighbors dialog box, do any of thefollowing:

• To perform an analysis using only the selectedrecords, enable the Find neighbors toselected input areas only check box.

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• To report which shapes border the selectedshapes, enable the Adjacent to the inputareas option.

• To include a region outside the boundary ofthe digitized areas on the layer, enable theReport outside area in result check box.This represents the global polygon or outsidearea, which appears as -1 in the AttributeManager.

• To report in separate records the results of ashape that borders another shape in differentplaces (not available for thematic rasters),enable the Report neighbor B as tworecords in result check box. For example, theperimeter of shape B touches shape A in twoplaces so you obtain two records for shape B.

• To report only the shapes that completelysurround another shape (for example, lakescontaining islands), enable the Input areassurround option.

• To report shapes that are surrounded by othershapes (for example, islands), click Inputareas are surrounded by option.

2. In the Input Areas column, enable the check marknext to the layer attributes that you want to add tothe Area Neighbors table.

3. In the Neighbors column, enable the check boxnext to the layer attributes that you want to add tothe Area Neighbors table.

If you want to select the records in the AttributeManager that correspond to the results, enable theSelect found neighbors option.

4. Click OK.

Creating a chart from the AttributeManager

You can generate a chart from vector, grayscale, andpseudo-color layers in the Maps tree, but not from bitmap(1-bit) or RGB layers. Charts are also available from theFiles tree on raster channels or vector segments.

When you create a chart, it compares the values of theselected records and fields in the layer attributes, orgraphs the pixel value counts from a raster withoutattributes.

For more information about charts, see Viewing data as achart on page 337 .

1. Right-click a layer that contains the data that youwant to chart and click Attribute Manager.

If you want to chart the pixel value counts from araster without attributes, you will have to createdefault attributes. When the message displays, clickOK to create the attributes.

2. In the Attribute Manager, select the fields andrecords that you want to chart.

3. In the main menu of the Attribute Manager, clickTools.

4. Click Charts and choose a chart type.

For more information about the Chart viewer, see Usingthe Chart Viewer on page 343 .

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Opening the Z-value Transfer dialogbox

If you have a Z-value as an attribute for a shape on anUnstructured, Line, Point, Whole Polygon, or TopologicalLine vector layer, you can transfer that value to theshape#s vertices. Conversely, you can also convert theZ-values from the shape#s vertices into an attribute.

The values for the vertices are not directly associated tothe attributes. If you change the Z-values for theattributes, it will not automatically update the vertices,and vice versa. If you want to update either the verticesor the attributes, you must repeat the Z-value transfer.

You can view the vertices of a shape with the Verticestool available in the Vector Editing toolbar (see Addingand removing: vertices on page 329 ).

• From the Edit menu in the Attribute Manager, clickZ-value Transfer.

Transferring Z-values from thevertices to a field

1. If you want to transfer the Z-value for the selectedrecords only, enable the Transfer Z-value ofselected shapes only check box.

2. Click Shape to attribute.3. In the Destination field list, click the field that you

want to receive the Z-value.

If you want to create a new field in the AttributeManager, click New Field. A default label calledZ-value is displayed in the Destination field list.You can rename the label to one of your choice.The field properties, except the data type, are set bydefault. You set the data type in step 4. To modifythe field properties, see Setting the field definitionson page 309 .

4. If you create a new field for the Z-value, the Typelist becomes available. In the Type list, click one ofthe following data types:

• Integer: defines the field for positive ornegative whole numbers

• Float: defines the field for single-precision realnumbers

• Double: defines the field for double-precisionreal numbers

5. In the Z-value aggregation list, click the methodthat you want to use to combine the Z-values fromthe vertices into an attribute for the shape. Click oneof the following methods:

• First: for each selected shape it uses theZ-value from the first vertex as the attribute.

• Last: for each selected shape it uses theZ-value from the last vertex as the attribute.

• Sum: for each selected shape it calculates thesum of the Z-values from the vertices anduses that value as the attribute.

• Mean: for each selected shape it calculatesthe average Z-value from the vertices anduses that value as the attribute. The averageis obtained by adding values from the verticesand dividing that value by the number of

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vertices used in the sum.• Minimum: for each selected shape it uses the

lowest Z-value from the vertices as theattribute.

• Maximum: for each selected shape it uses thehighest Z-value from the vertices as theattribute.

• Mode: for each selected shape it calculatesthe Z-value that occurs the most frequentlyamong the vertices and uses that value as theattribute.

• Median: for each selected shape it ranks theZ-values from the vertices in numerical order.The median is the middle value and it usesthat value as the attribute.

• Standard Deviation: for each selected shapeit measures the variation in the distribution ofZ-values, which is calculated from square rootof the variance, and uses that value as theattribute.

6. Click Transfer.

Transferring Z-values from a field tothe vertices

1. If you want to transfer the Z-value for the selectedrecords only, enable the Transfer Z-value ofselected shapes only check box.

2. Click Attribute to shape.3. In the Z-value field list, click the field that contains

the Z-values that you want to copy to the vertices.4. Click Transfer.

Exporting layer attributes to a file

1. From the Layer menu in the Attribute Manager,click Export Attributes.

2. In the Export Attributes dialog box, enable any ofthe following check boxes:

Save selected shapes only - saves only selectedrecords in the layer

Save selected fields only - saves only selectedfields in the layer

3. In the Output area, choose a file from the File listbox.

If a file is not listed, click Browse, locate and selecta file, and click Save.

4. Choose a file format from the Format list box.

If you want to modify the file format, click Optionsand make any changes in the GDB Options Editor.

5. Choose a layer from the Layer list box.6. Click Save.

Exporting the attributes to a text file

You can convert data in the Attribute Manager to anASCII delineated text file using the Export to Text dialogbox.

1. From the Layer menu in the Attribute Manager,click Export to Text.

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2. In the Export to Text dialog box, enable one of thefollowing options:

• Entire Table: exports the whole AttributeTable

• Visible Region: exports only the displayedrecords and fields

• If you want to export specific records andfields, choose a range of records next to Rowand choose a range of fields next to Column.

3. Click OK.

Opening GeoRasters from theAttribute Manager

A table in Oracle 10g Spatial can contain a large numberof records of geospatial data. Images stored in Oracle10g Spatial are called GeoRasters. Since opening a largenumber of GeoRasters can take a significant amount oftime, it may be more efficient for you to open only theirfootprints. A footprint is a vector representation of thespatial extents of the GeoRaster. By viewing thefootprints, you can make a more informed decision onwhich GeoRasters to open and, therefore, save yousome time.

GeoRasters are represented by a camera icon in theAttribute Manager. If a red cross appears on the cameraicon, it means that the GeoRaster is not available.

1. From the GeoRaster column in the AttributeManager, right-click a camera icon.

2. Click Add to Area.

Dissolving a boundary

Dissolve combines shapes that contain the same valuefor a selected attribute. The resulting output is a layer thatcontains the newly combined shapes with each shaperepresented as a layer record.

1. From the Analysis menu in the Focus window, clickDissolve.

2. In the Dissolve dialog box, choose a file from theFile list in the Input area.

If a file is not listed, click Browse, locate and selecta file, and click Open. If you choose Active Layer,the dissolve is performed on the current layer.

3. In the Output area, enable one of the followingoptions:

• Display: displays the results without savingthe new layer

• Save: saves the new layer in the project.Choose a file from the File list box and choosea layer from the Layer list box.

• If you want to display the results in the viewpane, enable the Display saved resultscheck box.

• If you want to use only the selected records,enable the Dissolve selected shapes onlycheck box.

4. In the Dissolve Option dialog box, enable one ofthe following options:

• Only adjacent shapes: combines all shapesthat share a common border and contain thesame value for the selected attribute or RSTstyle

• All shapes: forms one record for all the

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shapes on the layer that contain the samevalue for the selected attribute or RST style

• If you want to combine the adjacent pixels thatare diagonal to each other and that contain thesame value for the selected attribute or RSTstyle for thematic rasters, enable the Pixelsthat meet at a diagonal check box.

5. In the Dissolve Method area, enable one of thefollowing options:

• Representation Values: removes boundariesbetween shapes that contain the same key forthe representation of the layer

• Attributes: removes boundaries betweenshapes that contain the same attribute values

6. In the Based on column, enable the check box nextto the attributes you want to include.

If you want to add a field containing the number ofshapes combined to form each record in the output,enable the Add a count field check box.

7. Click OK.

For information about adding function or statistic fields tothe output Attribute Manager, see Adding function fieldsto output layers on page 320 .

Adding function fields to outputlayers

When you use Aggregate Attributes, Dissolve, orStatistical Overlay, you can add statistic and functionfields to the output layer Attribute Table, or both. Formore information, see Opening the Aggregate Attributes

dialog box on page 315 , Dissolving a boundary on page319 , and Using a statistical overlay on page 333 .

You can add fields using the simple or advancedmethods. With the simple method, you can add only onenew field per attribute. With the advanced method, youcan add several fields per attribute.

The statistic fields, Mean, Minimum, Maximum, Mode,Median, and Standard Deviation, are described in Settinga selected record statistics display on page 306 .

To add fields using the simple method

• From the Function column, click in an attribute celland choose a function or statistic.

To add fields using the advanced method

1. Click Advanced.2. Click in a column for the attribute.

A check mark indicates the selected functions andstatistics.

If you want to calculate the weighted average, clickin the Weighted Avg column next to the attributethat you want to use in the calculation and choosean attribute.

Working with shapesYou can use the Selection tools in the view pane and in

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the Symbol Editor to select, group, and attach shapes.

Selecting a single shape

When you select a shape in the view pane, its record isalso selected in the Attribute Manager. To select a recordin the Attribute Manager, see Selecting and clearingrecords and fields on page 307 .

1. From the Editing toolbar in the Focus window, clickthe Selection Tools arrow and choose Individual.

2. Click the shape that you want.

If you want to select another shape, press Shift andclick a shape.

Selecting shapes within or partiallywithin a circle

1. From the Editing toolbar in the Focus window, clickthe Selection Tools arrow and choose Circular.

2. Drag a circle over a location in the view pane.

If you want to add more shapes to your selection,press Shift and drag another circle.

Selecting shapes within or partiallywithin a polygon

1. From the Editing toolbar in the Focus window, clickthe Selection Tools arrow and choose Area.

2. Click in the view pane for each vertex you wantincluded in the area.

3. Double-click the last vertex.

All the shapes that are inside or that touch thepolygon are selected.

If you want to add more shapes to your selection,press Shift and digitize another polygon.

Grouping shapes

Grouping ties shapes from the same layer to act as asingle unit. Each shape in a group maintains its originalrepresentation and attributes. You cannot select ormodify grouped shapes individually; however, you canchange individual attribute values in the AttributeManager.

When you group shapes, a new field labeled GroupId isadded to the Attribute Manager. Focus assigns eachrecord in the group the same GroupId number.

1. Select the shapes you want to group.2. From the Edit menu in the Focus window, click

Group.

Ungrouping shapes

1. Select the grouped shapes that you want toseparate.

2. From the Edit menu in the Focus window, clickUngroup.

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Attaching shapes

Attaching combines shapes from the same layer into onerecord. The shapes appear as grouped in the view pane,but the records for the attached shapes are unified in arecord in the Attribute Manager. You can attach adjacentshapes, non-adjacent shapes, and shapes that arecontained within other shapes. Attached shapes arereferred to as rings.

You can use rings when separate shapes form a singleentity, such as a collection of islands forming one county,or when shapes are contained within other shapes, suchas an island in a lake.

1. Make sure the items are on the same layer.2. Select the items you want to attach.3. From the Edit menu, click Attach.

Separating shapes

1. Select the attached items.

This can be accomplished using the AttributeManager, by clicking on a group member, through awindow selector, or a query.

2. From the Edit menu, click Detach.

Creating buffers

A buffer is a margin created at a specific distance aroundshapes on a layer. You can create margins of different

sizes, each referred to as a buffer level.You use bufferlevels to analyse suitability or risk around the inputshapes, which is referred to as a proximity analysis.

For example, you can create a buffer around domesticwells to analyse the risk of contamination from pesticideuse.

• From the Analysis menu, click Buffer.

Creating buffers - step 1

1. In the Input area, choose a file from the File listbox.

If a file is not listed, click Browse, locate and selecta file from the File Selector dialog box, and clickOpen.

2. Choose a layer from the Layer list box.3. In the Output area, enable one of the following

options:• Display: shows the results without saving the

new layer• Save: saves the new layer to the project.

Choose a file from the File list box and choosea layer from the Layer list box.

• If you want to display the results in the viewpane, enable the Display saved resultscheck box.

• If you want to include only the selectedrecords in the layer, enable the Bufferselected shapes only check box.

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4. In the Buffer Distances area, enable one of thefollowing options:

• Simple: buffers all the selected shapes• Representation Values: buffers the selected

shapes according to their representationvalues

• Field: buffers the selected shapes accordingto an attribute. Choose an attribute from thelist box.

5. Enter a number of levels that you want in the Bufferlevels spin box.

6. Choose a unit of measurement from the Units listbox.

7. In the Buffer distances table, type a number ineach Level column to determine the width of abuffer.

8. Click Next.

Creating buffers - step 2

1. In the Vertex Options area, enable a corneringtype.

2. In the Line Options area, enable an option for theside you want the buffer to appear.

3. Enable an End style option for the style you want touse at the end of lines.

4. In the Polygon Options area, enable a style option.5. In the Fields to Add area, enable the

SourceShapeId check box.6. Enable any of the following check boxes:

• [attribute name]Value: includes the attributevalues in the output layer if the buffer is basedon an attribute and if overlapping buffers arekept separate

• BufferDistance: lists the width of the buffer foreach level in the output layer

• BufferLevel: lists the levels in the output layer7. In the Output Areas area, enable one of the

following options:• Combine: combines the shapes where the

buffers overlap• Keep Separate: keeps each buffer separate

8. Click Finish.

Editing vectors using the vectorediting tools

You can access the vector editing tools and the VectorEditing Tools toolbar from the Edit menu. A variety oftools are provided for editing vectors. Some of thechanges that you can make using the vector editing toolscan affect the attributes of the shape you are editing. Forexample, the Merge Line/Polygon tool combines twoshapes, including their attributes.

When you edit vectors in a Math Model Area (seeUnderstanding vector editing in a math model area onpage 302 ), the vertices are shown in the correct positionaccording to the math model and DEM, or theapproximate elevation value that you provided when youcreated the Area. Lines connecting the vertices arestraight and do not reflect the effects of the math modeland elevation.

1. Click a shape with the Individual Selection tool.2. From the Edit menu, click Vector Editing.

The vector editing tools on the Edit menu become

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available and the Vector Editing Tools toolbar aredisplayed.

About the Vector Editing tool barThe following table shows the available tools.

Table 21. Vector Editing tools

Tool Name Action

Find

Selects theshape andIdentifies thestart and endvertices.

Reverse Vertices

Changes linedirection (notavailable forwhole polygons).

Add VerticesCreates newvertices within ashape.

MergeLine/Polygon

Connects ends oflines together orcombinespolygons byremovingcommonboundaries.

SplitLine/Polygon

Breaks lines andpolygons into

Tool Name Action

separate shapes.

Extend LineExtends thelength of a vertexin a straight line.

Auto Merge Line

Removes thestart or endvertices sharedbetween lines(pseudo-nodes)

Close Shape

Automaticallyconnects thestart and endvertices of a lineto form apolygon.

Mirror Tools

Flips a shapehorizontally orvertically to makea mirror image.

Rotation ToolsRotates a shapearound ananchor.

BreakLine/Polygon

Separatesoverlappingshapes at theirintersectingpoints.

Start VertexMoves the cursorto the start vertexin a selected

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Tool Name Action

shape.

Previous Vertex

Moves the cursorfrom one vertexto the previousvertex in aselected shape.

Midpoint

Moves the cursorhalfway betweentwo vertices inthe direction ofthe line.

Next Vertex

Moves the cursorfrom one vertexto the previousvertex in aselected shape.

End Vertex

Moves the cursorto the end vertexin a selectedshape.

Show Vertex

Makes thevertices in ashape moreprominent forbetter visibility.

Vertices

Opens theVertices dialogbox and displaysthe vertexcoordinates of aselected shape.

Selecting a shape

The Find tool selects a shape and identifies the start andend vertices.

1. On the Vector Editing Tools toolbar, click the Findbutton.

2. Click a shape.

Moving a vertex

The Find tool selects a shape and identifies the start andend vertices.

1. On the Vector Editing toolbar, click the Find buttonand click a shape.

2. Click the Show Vertices button.3. Drag a vertex to a new location.

Moving several vertices togetherwhile maintaining their form

The Find tool selects a shape and identifies the start andend vertices.

1. On the Vector Editing Tools toolbar, click the Findbutton and click a shape.

2. Click the Show Vertices button.3. Press and hold the Ctrl key and select several

vertices4. Drag a selected vertex to a new location.

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Reversing vector direction

The Reverse Vertices tool changes the direction of theline (not available for whole polygons).

1. From the Vector Editing Tools dialog box, click theFind button and click a shape.

2. Click the Reverse Vertices button.

Adding vertices

The Add Vertices tool creates new vertices within ashape.

When you use this tool in a Math Model Area (seeUnderstanding vector editing in a math model area onpage 302 ), the elevation for the new vertex is derivedfrom the DEM or the approximate elevation value thatyou provided when you created the Area.

1. From the Vector Editing Tools dialog box, click theFind button and click a shape.

2. Click the Add Vertices button.3. Click on the line where you want the vertex.

If you want to continue a line, click the start or endvertex of the line and click a series of vertices.

Connecting lines

The Merge Line/Polygon tool connects ends of linestogether or combines polygons by removing commonboundaries. This tool may affect the attributes of the

shape you are editing.

1. From the Vector Editing Tools dialog box, click theFind button and click a line.

2. Click the Merge Line/Polygon button.3. Click the start or end vertex of the line.4. Click the start or end vertex of a line with which you

want to merge the first line.

Connecting polygons

1. Click the Find button and click a polygon.2. Click the Merge Line/Polygon button.3. Click a polygon with which you want to merge the

first polygon.

Cutting a line

The Split Line/Polygon tool cuts lines and polygons intoseparate shapes. This tool may affect the attributes of theshape you are editing.

When you use this tool in a Math Model Area (seeUnderstanding vector editing in a math model area onpage 302 ), the elevation for the new vertex created atthe cut point is derived from the DEM or the approximateelevation value that you provided when you created theArea.

1. From the Vector Editing Tools dialog box, click theFind button and click a line.

2. Click the Split Line/Polygon button.3. Click where you want to split the line.

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When you split a polygon, you draw a line through theshape where you want the polygon to split.

Cutting a polygon

1. Click the Find button and click a polygon.2. Click the Split Line/Polygon button.3. Click a point on the outline of the polygon where

you want to begin a line.4. Click in the polygon to form the line.5. Double-click a point on the outline of the polygon to

end the line.

Extending a line

You can move a start or end vertex simply by selectingthe vertex with the Find tool and moving it. However, ifyou want to extend the line without changing its angle,the Extend Line tool forces the vertex to move in astraight line.

When you use this tool in a Math Model Area (seeUnderstanding vector editing in a math model area onpage 302 ), the elevation for the new vertex is derivedfrom the DEM or the approximate elevation value thatyou provided when you created the Area.

1. From the Vector Editing Tools dialog box, click theFind button and click a line.

2. Click the Extend Line button.3. Click a start or end vertex.4. Click where you want to end the extension.

Merging segmented lines

The Auto Merge Line tool removes the start or endvertices shared between lines (pseudo-nodes). If a line#sstart and end vertices connect, it automatically forms apolygon. This tool may affect the attributes of the shapeyou are editing.

1. From the Vector Editing Tools dialog box, click theFind button and click a line.

2. Click the Auto Merge Line button.3. Click the start or end vertex where you want to

begin merging the line.

If it reaches a fork in the line, you must choosewhich line to follow. Click the line that you want tomerge.

Changing a line into a polygon

The Close Shape tool automatically connects the startand end vertices of a line to form a polygon.

1. From the Vector Editing Tools dialog box, click theFind button and click a line.

2. Click the Close Shape button.

Flipping a shape to its mirror image

The Mirror tools flip the shape horizontally or verticallyresulting in the mirror image of the shape.

When you use this tool in a Math Model Area (see

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Understanding vector editing in a math model area onpage 302 ), the shape is flipped according to the groundcoordinates and may be mirrored about oblique axes,which may cause the it to appear distorted.

To flip a shape

1. From the Vector Editing Tools dialog box, click theFind button and click a shape.

2. Click the Mirror Tools button.

To switch the Mirror tools from horizontal tovertical

1. Click the Mirror Tools arrow and choose one of thefollowing:

• Mirror X: flips a shape vertically• Mirror Y: flips a shape horizontally

Spinning a shape free hand

The Rotation tools revolve a shape around an anchor. Bydefault, the start vertex is the anchor when a Rotationtool is selected. To move the anchor, click it and move it.

When you use this tool in a Math Model Area (seeUnderstanding vector editing in a math model area onpage 302 ), the elevation for each vertex in the shape isderived from the DEM or the approximate elevation valuethat you provided when you created the Area.

1. From the Vector Editing Tools dialog box, click theFind button and click a shape.

2. Click the Rotation Tools arrow and click FreeRotate.

3. Drag the shape to the angle you want.

Spinning the shape precisely

1. Click the Find button and click a shape.2. Click the Rotation Tools arrow and click Rotate by

Angle.3. In the Rotate by Angle dialog box, enter a value for

the angle by which you want to rotate the shape inthe spin box.

4. Choose an angle unit from the list box.5. Click OK.

Separating overlapping shapes

The Break Line/Polygon tool separates overlappingshapes at their intersecting points. For example, if youhave two overlapping polygons, the Break Line/Polygontool separates the two polygons into three with theoverlap area becoming the third polygon. This feature isnot available for a topological layer, because overlappingshapes are automatically separated. This tool may affectthe attributes of the shape you are editing.

1. From the Vector Editing Tools dialog box, click theFind button and click a shape.

2. Click the Break Line/Polygon button.3. Click the overlapping shape outside of the overlap

area.

Moving the cursor to the start vertex

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You can select a vertex by clicking it or you can use oneof the navigation tools.

Start Vertex and End Vertex

Moves the cursor to the start vertex or end vertex of aselected shape.

1. From the Vector Editing Tools dialog box, click theFind button and click a shape.

2. Click the Start Vertex button.

Moving the cursor to the end vertex:

1. Click the Find button and click a shape.2. Click the End Vertex button.

Previous Vertex and Next Vertex

Moves the cursor from one vertex to another in aselected shape. The Previous Vertex tool moves thecursor toward the start vertex; the Next Vertex tool movesthe cursor toward the end vertex.

Moving the cursor along vertices

1. Click the Find button and click a shape.2. Click the Previous Vertex button or the Next

Vertex button.

Midpoint

TMoves the cursor halfway between two vertices in thedirection of a line.

Moving the cursor to a vertex

1. Click the Find button and click a shape.2. Select a vertex.3. Click the Midpoint button.

Displaying vertices

The Show Vertices tool makes the vertices in the shapemore prominent so they more easily seen.

1. From the Vector Editing Tools dialog box, click theFind button and click a shape.

2. Click the Show Vertices button.

Adding and removing: vertices

To display coordinates, select a shape with the Find tooland click the Vertices button. The Vertices dialog boxdisplays the coordinates of the vertices contained in theselected shape.

If you select a vertex in the view pane and move it, thecoordinates are automatically updated. You can also addor subtract vertices from the Vertices dialog box. Whenyou add a vertex, it is inserted halfway between theselected vertex and the next according to the direction ofthe line.

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1. Select a vertex in the Vertices dialog box and dothe following:

• To add vertices, click the Add button.• To delete a vertex, click it and click the

Remove button.

The coordinate system for the Area in the Maps tree isdetermined by the first layer opened in the Area. Whenyou add layers to the Maps tree, you have the choice ofusing the same coordinate system or a different one. Ifthe coordinate system for the layer is different than that ofthe Area, you can display the coordinates of the verticesin either systems.

Switching between coordinatesystems

1. To view the vertices using the coordinate system ofthe Area in the Maps tree, click Area underCoordinate System.

2. To view the vertices using the coordinate system ofthe layer, click Layer under Coordinate System.

Selecting vectors using spatial querytoolsSpatial Query tools search through all visible layers toselect the shapes that correspond to your criteria.

Including an original selection in aspatial query

When you use any of the Spatial Query tools, you caninclude or exclude your original selection from theresulting selection. When you enable the Add toSelection option, the results of the Spatial Query areselected along with your original selection. When youclear Add to Selection, only the results of the SpatialQuery are selected.

• From the Editing toolbar, click the Spatial Queryarrow and choose Add to Selection.

A check mark next to the option indicates it isenabled.

Selecting fully contained shapes

The Fully Within tool selects all other shapes that fallcompletely within a selected shape or area. Any shapethat touches or overlaps a shape other than the one youselected will not be included.

1. From the Editing toolbar, click the Selection Toolsarrow and choose a tool.

2. Click a shape or select an area.3. From the Editing toolbar, click the Spatial Query

arrow and choose Fully Within.

Selecting partially contained shapes

The Partially Within tool selects the shapes that have atleast one vertex in common with a selected shape orarea, including overlapping and neighboring shapes.

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1. From the Editing toolbar, click the Selection Toolsarrow and choose a tool.

2. Click a shape or select an area.3. From the Editing toolbar, click the Spatial Query

arrow and choose Partially Within.

Selecting all shapes within a specifieddistance

The Within Distance tool selects shapes that fallcompletely or partially within a specified distance of aselect shape or area. If you do not select a shape orarea, the distance is calculated from the location of thecursor.

1. From the Editing toolbar, click the Selection Toolsarrow and choose a tool.

2. Click a shape or select an area.3. From the Editing toolbar, click the Spatial Query

arrow and choose Within Distance.4. In the Within Distance dialog box, type a number in

the Distance box.5. Choose a unit of measurement from the list box.6. Click OK.

Selecting all shapes fully within adistance

The Fully Within Distance tool selects only shapes thatfall completely within a specified distance of a selectedshape. If you do not select a shape, the distance iscalculated from the location of the cursor.

1. From the Editing toolbar, click the Selection Tools

arrow and choose a tool.2. Click a shape or select an area.3. From the Editing toolbar, click the Spatial Query

arrow and choose Fully Within Distance.4. In the Within Distance dialog box, type a number in

the Distance box.5. Choose a unit of measurement from the list box.6. Click OK.

Selecting intersecting shapes

The Crosses tool selects all of the shapes that intersectselected shapes.

1. From the Editing toolbar, click the Selection Toolsarrow and choose a tool.

2. Click a shape or select an area.3. From the Editing toolbar, click the Spatial Query

arrow and choose Crosses.

About the Overlay wizardAn overlay derives information from two or more inputlayers. The Overlay Wizard contains three overlay types:Spatial Overlay, Statistical Overlay, and SuitabilityOverlay.

Spatial Overlay forms a new layer containing theattributes from two or more layers. For more information,see Combining layers with a spatial overlay on page 332 .

Statistical Overlay transfers the selected attributes fromlayer to another. For more information, see Using astatistical overlay on page 333 .

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Suitability Overlay analyses the relative importance ofinput layers and attributes to identify the areas thatproduce the most positive result. For more information,see Using a suitability overlay on page 334 .

Combining layers with a spatialoverlay

Spatial Overlay forms a new layer containing theattributes from two or more layers. For example, you canoverlay a layer containing land-ownership polygons and alayer containing vegetation polygons to analyse wherethe types of vegetation are located on each property. Ifyou want to overlay specific shapes from the layers,select them before you begin the Spatial Overlay.

1. From the Analysis menu, click Overlay.2. In the Overlay Wizard, enable the Spatial option

and click Next.3. In the Available Files/Layers list, enable the check

mark next to the layers that you want to combine.• If you want to select layers from another file,

click Browse, locate and select a file from theFile Selector dialog box, and click Open.

• If you want to overlay only the selected shapesin each layer, enable the Overlay only theselected shapes of the input layers checkbox.

4. Click Next.5. Choose a layer from the Layer list box.6. Select an attribute that you want to include in the

new layer from the Input Attribute list.7. Click Add.

8. Repeat step 5 to step 7 for each layer.

If you want to change the order of an attribute,select it in the Attribute table and click the up ordown arrow buttons.

9. If you want to change the names of an attribute,double-click it and type a new name.

10. Click Next.11. In the Output Options area, enable one of the

following options:• Union: includes all shapes in their entirety

from all the input layers• Intersection: includes only the overlapping

areas of the shapes from the input layers12. Enable any of the following check boxes:

• Use a Mask to Limit Output: uses a layer tolimit the area. Choose a layer from the list box.

• Using Only Selected Shapes: includes onlythe selected shapes as the mask

• Use a Named Region to Limit Output: usesan existing named region as the mask. Formore information about Named Regions, seeCreating named regions on page 79 .

13. In the Output Layer area, select a layer type for thenew layer from the Type list box.

14. Enable one of the following options:• Display: shows the results without saving the

new layer• Save: saves the new layer in the project.

Choose a file from the File list box and choosea layer from the Layer list box.

• If you want to display the results in the viewpane, enable the Display saved resultscheck box.

15. Click Finish.

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Using a statistical overlay

Statistical Overlay transfers the selected attributes fromone layer to another. One layer, called the Primary Input,receives the attributes from another layer, called theSecondary Input.

There are two possible results when you transferattributes between the layers:

• Each shape in the Primary Input can receive theattributes from one shape in the Secondary Input.For example, you can transfer the county attributesfrom a county layer to a cities layer. Each city in thePrimary Input receives the attributes from thecounty that contains the city.

• Each shape in the Primary Input can receive theattributes from many shapes in the SecondaryInput. You must specify a function to aggregate theattributes from the Secondary Input. For example,you can transfer the city attributes from a cities layerto a county layer. Each county in the Primary Inputreceives the sum of the population of the citiescontained within that county.

1. From the Analysis menu, click Overlay.2. In the Overlay Wizard, enable the Statistical option

and click Next.3. In the Primary Input area, choose a file from the

File list box.

If a file is not listed, click Browse, locate and selecta file from the File Selector dialog box, and clickOpen.

4. Choose a layer that will receive the attributes from

the Layer list box.

If you want to include only the selected records inthe layer, enable the Use selected shapes onlycheck box.

5. In the Secondary Input area, choose a file from theFile list box.

6. Choose a layer that contains the attributes you wantto add to the Primary Input layer from the Layer listbox.

If you want to include only the selected records inthe layer, enable the Use selected shapes onlycheck box.

7. Click Next.8. Click Finish.

You can add function fields to the output AttributeManager. (See Adding function fields to output layers onpage 320 )

You can also add fields containing other attributes. (SeeAdding attributes to the statistical overlay output on page 333)

Adding attributes to the statisticaloverlay outputThe Primary and Secondary Input layers that you choosefor the Statistical Overlay determine the availability of theGrouping Criteria options and the options availableunder Additional Attributes.

Count

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is available when:

• The Primary Input is a line layer and the SecondaryInput is a line, polygon, thematic raster, or raster.

• The Primary Input is a polygon layer and theSecondary Input is a point, line, polygon, thematicraster, or raster.

• The Primary Input is a thematic raster layer and theSecondary Input is a point, line, polygon, thematicraster, or raster.

When you enable the Count check box, Focus calculatesthe number of shapes combined to form each record andadds that attribute the output layer.

Surface Length

is available when the Primary Input is a line layer and theSecondary Input is a raster. This option is useful if theraster is a DEM. When you enable the Surface Lengthcheck box, Focus calculates the three-dimensionalsurface length of the line and adds that attribute theoutput layer.

Distance

is available when:

• The Primary Input is a point layer and theSecondary Input is a point, line, or polygon layer.

• The Primary Input is a line layer and the SecondaryInput is a points layer.

When you enable the Distance check box, Focusidentifies the shape from the Secondary Input that is theclosest to each shape in the Primary Input and calculates

the distance between them. The distance is added toeach record in the output layer. When points arecontained within the polygon, the distance equals zero inthe output.

Counting Specific Pixel Values:

You can count specific pixel values when the PrimaryInput is a line, polygon, or thematic raster layer and theSecondary Input is a raster. For each line in the PrimaryInput, Focus identifies corresponding pixels in theSecondary Input and adds that attribute the output layer.

Grouping Criteria:

The Grouping Criteria options are available when thePrimary Input is a polygon layer and the Secondary Inputis a line or polygon layer.

To combine all shapes from the Secondary Input thattouch or overlap the boundaries of each shape in thePrimary Input, enable the Partially Within option. Theresulting attribute is added to the output layer.

To combine only the shapes from the Secondary Inputthat lie entirely within the boundaries of each shape in thePrimary Input, enable the Wholly Contained option. Theresulting attribute is added to the output layer.

Using a suitability overlay

Suitability Overlay analyses the relative importance ofvarious data to identify areas that produce the most

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positive result. For example, analysing data in a project toidentify the best location for a school or the most likelylocation for a forest fire.

To perform the analysis, you must build a projectcontaining layers of data that you want to use in thecalculation. Each layer should contain one type of datarepresenting a factor in the calculation. For example, ifyou are trying to determine the best location for a winery,your project could contain a layer with rainfall levels foran area, a layer of soil types found in the area, a layercontaining the road network, and so on.

To calculate a combination that produces the best result,you must decide on a scale to rank the importance thelayers and a scale to rank the data in the layers. Thescales measure the relative importance of each input intothe equation; the most important factors affect the resultsthe most. The value from the scale that you assign to thelayer and to the data is called a weight. For moreinformation about how to determine the scales, seeUnderstanding weights in the suitability overlay on page 336.

For example, you have a scale of 1 to 100 for the layers.Because the soil type layer is more important than theroad network layer, you can assign a weight of 75 to thesoil type layer and a weight of 25 to the road networklayer; the soil type layer is three times more influential inthe calculation than the road network layer.

You do not need to use the same scale for the layers andthe data in the layers, but you should use one scale forthe layers themselves and one scale for the data in the

layers. Weighting the data in one layer according to avastly different scale from the data in the other layers canskew the results.

To add weights to data, add a field in the AttributeManager for each layer and enter the numeric valueexpressing the weight for the data in each record. Anegative weight for a record will force an unfavorableresult in the output for that record.

For example, you have a scale of 1 to 10 for the data inthe layers. In the soil type layer, you assign thewell-drained soils an 8, the poor and shallow soils a 2,and the polluted soils a -1. Any sites containing pollutedsoils will automatically receive a negative result.

You must also assign a weight to the'No Data' value inthe layers. The'No Data' value represents the null valuesor the pixels without data. The'No Data' value is usuallyset in the metadata of the layer so it may not appear inthe Attribute Manager. When you assign a weight tothe'No Data' value in step 7, you should use the samescale as the rest of the data in the layers.

When setting up a Suitability Overlay, you mustdetermine the weight of each layer, the weight of theNoData value, and select the field that contains theweights for the data in each layer. The result is displayedin a layer indicating the most positive correlation betweenall the factors in the equation.

1. From the Attribute Manager, add a field to eachlayer containing the numeric value expressing theweight of the records. For more information, see

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Adding new fields on page 309 .2. From the Analysis menu in the Focus window, click

Overlay.3. In the Overlay Wizard, enable the Suitability option

and click Next.4. In the Available Files/Layers list, enable the check

mark next to the layers that you want to combine.

If you want to select layers from another file, clickBrowse, locate and select a file from the FileSelector dialog box, and click Open.

5. Click Next.6. Type a number to determine the weight of each

layer in the Layer Weight column.7. Type a number to determine the weight of NoData

value for each layer in the NoData Weight column.

Use the same weight scale as you used for theattributes.

8. In the Attribute Weight column, click a cell andchoose the weight values for the attributes.

9. Click Next.10. In the Output Options area, enable one of the

following options:• Union: includes all the shapes in their entirety

from all input layers• Intersection: includes only the overlapping

areas of shapes from the input layers11. Enable any of the following check boxes:

• Use a Mask to Limit Output - uses a layer tolimit the area. You can use an existing abitmap, raster, or polygon layer. Choose alayer from the list box.

• Using Only Selected Shapes - includes onlythe selected shapes as the mask

• Use a Named Region to Limit Output - se anexisting named region as the mask. For moreinformation about Named Regions, seeCreating named regions on page 79 .

12. In the Output Layer area, enable one of thefollowing options:

• Display - shows the results without saving thenew layer

• Save - saves the new layer in the project.Choose a file from the File list box and choosea layer from the Layer list box.

• If you want to display the results in the viewpane, enable the Display saved resultscheck box.

13. Click Finish.

Understanding weights in thesuitability overlayThe range of numbers that you select for a scale doesnot have an inherent value; it is the degree of value in thescale that gives them their value.

For example, if you use a scale of 1 to 10 and assign aweight of 2 to the Road Network layer and a weight of 5to the Rainfall layer, it has the same effect as using ascale of 1 to 100 and giving Road Network layer a weightof 20 and the Rainfall layer a weight of 50. In each case,the Rainfall layer has more weight and is consideredbetter or more desirable in the calculation.

The scale for the layers is usually based on a scale of 1to 100, but the sum of the layer weights does not need toequal 100. The point is to identify the relative importance

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of each layer in comparison with the others.

The scale of the data in the layers does not have to bethe same as that used for the layers, but the scale shouldbe consistently applied for all the data. Using differentscales for the data in different layers may causeunwanted results.

For example, if you used a scale of 1 to 1000 to rank thedata in the Soil Types layer and a scale of 1 to 10 for thedata in the other layers, the soil types might nullify theimportance of other data like rainfall even if the Rainfalllayer itself has a higher weight than the Soil Type layer.

Viewing data as a chartCharts are a way to visualize your data. A chart is a tableof attributes displayed as a graphic where the values ofselected records and fields are compared. It displaysquantitative data so you can see how the numbers relateto each other, which helps you to interpret the informationmore easily. Trends or anomalies may become evidentwhen displayed using the right chart type. For example, itmay be difficult to identify trends by looking at a tablefilled with population statistics, but with the right chart thepattern become easily discernable.

For column, bar, line, area, and pie chart types, you mustselect at least one field and one record before the chart isdisplayed in the viewer. For the scatter chart type, theminimum number of selected records and fields dependson the Series in setting. When Series in is set to Records,you must select at least two fields and at least one recordbefore the chart is displayed. When Series in is set to

Fields, at least one field and at least two records must beselected. If the minimum number of selected records andfields for any chart type is not satisfied, the chart displaysa message reminding you to select data.

You can create more than one chart per layer. Each chartis connected to the attributes in the layer so if theattribute values change, the chart changes to reflect thenew values. Each chart that you create is remembered inthe Chart Manager. For more information, see Openingand deleting a chart on page 348 .

About chart typesThe trick with charts is to use the right chart type todisplay your data. One chart type can make your datainstantly understandable while another can completelyconfound it.

Column:

The column chart type displays the selected data asvertical stripes of different colors or patterns. Thecategories are organized along the x-axis (horizontally)and the values are measured along the y-axis (vertically).Column charts are often used to compare data or toemphasize how data changed over time.

Three options are available for the column chart:

• The Clustered Column type forms separate bandsfor each kind of data and groups the bandsside-by-side by category.

• The Stacked Column type forms bands for each

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kind of data and piles the bands on top of oneanother to form one column per category.

• The 100% Stacked Column type is similar to theStacked columns type, except each band isexpressed as a percentage and each column totals100%. The Stacked columns and Percent columnsillustrate the contribution of each band to the wholecategory.

Bar:

The bar chart type displays the selected data ashorizontal stripes of different colors or patterns. Incontrast with the column chart type, the values areorganized along the x-axis (horizontally) and thecategories are measured along the y-axis (vertically). Barcharts are often used to compare data while reducing theemphasis on the passage of time.

Three options are available for the bar chart:

• The Clustered Bar type forms separate bands foreach kind of data and groups the bandsside-by-side by category.

• The Stacked Bar type forms bands for each kind ofdata and lines up the bands end to end to form onecolumn per category.

• The 100% Stacked Bar type is similar to theStacked bar type, except each band is expressedas a percentage and each column totals 100%. TheStacked bar and Percent bar charts illustrate thecontribution of each band to the whole category.

Line:

The line chart displays the selected data as lines of

different colors or patterns connecting points at equalintervals. The categories are organized along the x-axis(horizontally) and the values are measured along they-axis (vertically). The vertices represent the values foreach category and the angles formed by the linesconnecting the vertices emphasize the trends.

Three options are available for the line chart:

• The Line type creates a line for each kind of datawhere each vertex represents the actual value foreach category.

• The Stacked Line type creates a line for each kindof data where each vertex represents the value ofeach category added to the value of the vertexbeneath it. Therefore, the topmost vertex in eachcategory reflects the sum total of all the data in thatcategory.

• The 100% Stacked Line type is similar to theStacked line type, except each line is expressed asa percentage and each category totals 100%. TheStacked line and Percent line types illustrate thecontribution of each line to the whole category.

Area:

The area chart displays the selected data as polygons ofdifferent colors or patterns connecting points at equalintervals. It is similar to the line chart, except the areabelow the line is shaded to form a polygon. Thecategories are organized along the x-axis (horizontally)and the values are measured along the y-axis (vertically).The points represent the values for each category andthe angles formed by the lines connecting the pointsemphasize the trends.

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Three options are available for the area chart:

• The Area type creates a polygon for each kind ofdata where the points represent the actual value foreach category.

• The Stacked Area type creates a polygon for eachkind of data where each point represents the valueof each category added to the value of the pointbeneath it. Therefore, the topmost point in eachcategory reflects the sum total of all the data in thatcategory.

• The 100% Stacked Area type is similar to theStacked Area type, except each polygon isexpressed as a percentage and each categorytotals 100%. The Stacked Area and 100% StackedArea types illustrate the contribution of eachpolygon to the whole category.

Pie:

The pie chart is a circular graphic which displays the dataas wedges representing their portion of the whole. It canonly show the portions or ratios of one kind of data at atime.

Two options are available for the pie chart:

• The Pie type creates a circle divided into slicesproportional to the whole.

• The Exploded Pie type creates a circle broken intoslices proportional to the whole.

Scatter:

The scatter chart is a graph of points comparing two setsof data. One set is plotted along the x-axis and the other

along the y-axis. It is used to uncover a possiblecorrelation between the data sets.

The appearance of a discernable pattern or clustering ofthe points indicates a correlation between the data sets.An indicator of a high correlation between the data sets isthat you are able to draw a straight line through thepoints. The more points that cluster about the impliedline, the stronger the possibility of a correlation. If thepoints appear randomly distributed over the chart, it isunlikely that a correlation exists.

It is important to note, however, that although a scatterchart may indicate a correlation between the data sets itdoes not mean that one data set is causing an affect onthe other. The correlation can be the result of a thirdfactor affecting both sets or can be simply a coincidence.

Creating a chart from the layer

You can generate a chart from vector, grayscale, andpseudocolor layers on the Maps tab, but not from bitmap(1-bit) or RGB layers. Charts are also available from theFiles tab on raster channels or vector segments.

When you create a chart, it compares the values of theselected records and fields in a layer#s attributes orgraphs the pixel value counts from a raster withoutattributes.

1. In the Maps tree, select the layer that contains thedata that you want to chart.

2. If you want to select specific shapes to chart from a

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vector or thematic raster layer, click the SelectionTools arrow on the Editing toolbar and select atool. In the view pane, click or drag to select theshapes that you want included in the chart.

3. In the Focus main menu, click Layer.4. Click Charts and select a chart type from the list.5. In the Chart viewer toolbar, click the Chart

Definition button.6. Select the fields, see Defining the data to chart on

page 340 .7. Click OK.

Defining the data to chart

Depending on which chart type you choose, you need toselect a minimum number of records and fields (seeAbout chart types on page 337 ). If the minimum numberof selected records and fields for any chart type is notsatisfied, the chart displays a message reminding you toselect data.

1. In the Type list, select the chart type that you wantto use to display your data. For more information onthe chart types, see About chart types on page 337.

2. Under Fields, click to select the fields that you wantto include in the chart. Only the fields with a blackcheck mark are included in the chart.

3. For Series in, select Fields to display the data fromthe selected Fields or select Records to display thedata from the selected records. For moreinformation, see About Series In on page 340 .

4. To customize the look of chart, click the Optionstab. For more information, see Designing the chartsurround on page 341 .

5. Click OK.

About Series InThe Series In option on the Chart Definitions dialog boxdefines what is displayed in the graph. Depending onwhat you want the data to be interpreted, you may wantto emphasize either the records or the fields. When youselect Records, the data in each record is represented inthe chart. When you select Fields, the data is displayedby field in the chart.

For example, when you choose Fields for the chartshown in the following figure, the fields are displayed asbars (Pop2000 and Pop2002). When you chooseRecords, the records (Alaska, California, and Florida) aredisplayed as bars.

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Understanding Series In:

Designing the chart surround

A chart's purpose is to display data so that we can quicklygrasp its meaning. The chart surround is a collection ofgraphical elements that gives meaning or clarifies the

meaning of the data displayed in a chart. It puts the datainto context so we can analyse, organize, andcommunicate the information effectively.

The chart surround elements include:

• Title and subtitle• The x-axis and its ticks, labels and headings• The y-axis and its ticks, labels and headings• The legend• The background• The data labels

Each chart surround element helps to present the data asclearly as possible. You do not need to include everyelement in every chart. Select the ones that mosteffectively convey the chart's meaning.

1. On the Chart Definition dialog box, click theOptions tab.

2. In the Title box, type a word or phrase that youwant as a title for your chart.

3. In the Subtitle box, type a word or phrase that youwant as a subtitle for your chart.

4. In the Category field list, select the field that mostclearly describes the records used in the chart. Formore information, see About the category field onpage 342 .

5. In the X-axis heading box, type a word or phrasethat you want to display along the bottom of thechart.

6. Select Show X-axis values to display the datavalues along the x-axis of the chart.

7. In the Y-axis heading box, type a word or phrasethat you want to display along the y-axis of thechart.

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8. Select Show Y-axis values to display the datavalues along the y-axis of the chart.

9. Select Show legend to display the legend for thedata in the chart.

10. Select Show data labels to display labels on thedata in the chart.

11. In the Background style list, click to select a stylefor the area behind the chart. You can create aframe around the chart or color the background. Formore information about creating styles, seeSelecting a style on page 354 .

12. Click OK.

NOTE: The Restore to Defaults button clears thepreference file for the chart, not just the settings on theOptions tab. For more information, see Resetting thechart to defaults on page 343 .

About the category fieldThe Category field list on the Chart Definition dialog boxdetermines which field is used to identify the recordsused in the chart. It affects what is displayed on thex-axis, the legend, or the y-axis depending on the charttype and the Series in setting.

Table 22.

Chart Type Series in: Fields Series in:Records

Category fielddisplays on:

Category fielddisplays on:

Column x-axis legend

Chart Type Series in: Fields Series in:Records

Category fielddisplays on:

Category fielddisplays on:

Bar y-axis legend

Line x-axis legend

Area x-axis legend

Pie legend not displayed

Scatter not displayed legend

The field that you select depends on what you want toemphasize or what attribute most clearly represents thedata in your chart. For example, in the following figure thechart displays the same data: the number of houses andapartments for each newspaper route. If you have newcustomers to add on Second Avenue which falls alongboth route 15 and 22, Chart A is going to be less helpfulunless you have memorized the names of the couriersresponsible for the routes. Chart B, on the other hand,gives you the route number immediately.

Understanding the Use of the Category Field

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Resetting the chart to defaults

When you create your first chart, the look of the chart isset by default. As you select the colors, fonts, and otherdesign options, Focus retains your choices in apreference file so the next time you create a chart, thelast used styles are applied to your current data. If youclick the Restore to Defaults button on the ChartDefinition dialog box, it clears the preference file for thechart, not just the settings on the Options tab.

1. In the Chart viewer toolbar, click the Chart

Definition button.2. On the Chart Definition dialog box, click the

Options tab.3. Click Restore to Defaults.4. Click Apply.

Using the Chart Viewer

The Chart Viewer consists of a view pane and a toolbar.The view pane contains the chart and the chart surrounditems. It serves as your workspace for creating yourchart. The toolbar provides quick access to various toolsand dialog boxes that you can use to design your chart.

To select a chart surround element or part of thechart

1. Click the Selection Tool button.2. Click the item in the viewer.

To lock the record and field selection in thechart

1. Click the Lock Chart button.

When you lock the chart, it only prevents changesto which records and fields are used by the chart.You can continue to modify the chart surroundelements and attribute values. Once the chart isunlocked, the chart is automatically updated withthe currently selected records and fields.

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To switch from chart type to another

1. Click the arrow next to Chart Type.2. Click the type that you want to use.

For more control over the chart settings, seeDefining the data to chart on page 340 .

To show or hide the chart legend

• In the Chart dialog box, click the Legend button.

For more control over the legend settings, seeDesigning the chart legend on page 345 .

To export the chart as a file

1. In the Chart dialog box, click Export Chart.

For more information, see Opening the Export Mapdialog box on page 407 .

To zoom in or out of the chart

1. Click the Zoom to Overview button to decrease themagnification so the whole chart appears in theviewer.

2. Click the Zoom Interactive button and drag arectangle over an area to magnify a specific part ofthe chart.

3. Click the Zoom In button to increase themagnification by increments and centers the chart in

the viewer.4. Click the Zoom Out button to decrease the

magnification by increments and centers the chart inthe viewer.

To move the magnified chart around with thepointer

1. In the Chart dialog box, click Pan and drag thepointer in the chart viewer.

To display the attributes from a chart

1. In the Chart viewer, click the Information button.2. Click a piece of data in the chart.

The clicked data flashes in the viewer and theattributes from that record are displayed underValues on the Information Report dialog box.

When used from the Chart toolbar, the Information tooldisplays all the attributes from the record correspondingto the data clicked in the chart. The Information tool isalso used in other places in Focus. For more information,see Using the information report on page 205 .

To change the color of the a part of the chart orchart surround elements

1. In the Chart viewer, click the Selection Tool button.2. Click the item in the viewer.3. On the Chart viewer toolbar, click the arrow next to

the Color button.

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4. Click a color from the palette or click More Colorsto create a color.

To change the look of a part of the chart or achart surround element

1. Click the Selection Tool button.2. Click the item in the viewer.3. Click the arrow next to the Style button.4. Click the style that you want. Different styles are

available depending on the item that you chose. Tocreate a new style, select Style Selector. For moreinformation about the Style Selector, see Selectinga style on page 354 .

To customize the chart

1. In the Chart dialog box, click the Chart Definitionbutton.

For more information, see Defining the data to charton page 340 .

To edit or position the chart surround elements

1. Click the Selection Tool button.2. Click the item in the viewer.3. Click the Properties button.

Designing the chart legend

The chart legend is a table listing and describing therepresentation of the data in the chart. If you deleted the

legend from the chart viewer, you can enable it from theOptions tab on the Chart Definition dialog box (seeDesigning the chart surround on page 341 ).

To open the Legend Properties dialog box

1. In the Chart viewer toolbar, click the Selection Toolbutton.

2. Click the legend.3. In the Chart viewer toolbar, click the Properties

button.

To design the legend

1. In the Field list (if available), select the field thatmost clearly describes the records used in the chart.For more information, see About the Category fieldon page 342 .

2. In the Size list, type or select the size of the fontused to identify the data in the chart.

3. In the Color list, select the color that you want touse for the font. To modify the color, click More. Tochange the font, click Selector. For moreinformation about the Selector, see Selecting a styleon page 354 .

4. Under Placement, click to select the position of thelegend in reference to the chart or drag the legendinto position.

5. Click OK.

Opening the X-axis or Y-axisProperties dialog box

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The labels identify the values along the x-axis and y-axis.

1. In the Chart viewer toolbar, click the Selection Toolbutton.

2. Click either the axis, the axis heading, or the axisvalues.

3. In the Chart viewer toolbar, click the Propertiesbutton.

Customizing the axis heading

1. On the X-axis or Y-axis Properties dialog box,click the Labels tab.

2. In the Axis heading box, type a word or phrase thatyou want to display along the axis of the chart.

3. In the Size list, type or select the size of the fontused for the axis heading.

4. In the Color list, select the color that you want touse for the font. To modify the color, click More. Tochange the font, click Selector. For moreinformation about the Selector, see Selecting a styleon page 354 .

5. In the Angle box, type a value between +90degrees and -90 degrees representing the rotationthat you want to apply to the axis heading. In the listselect the unit of angular measurement.

6. To keep the characters in the heading parallel to thex-axis, select Keep characters horizontal.

7. Click OK.

Customizing the axis tick labels

1. On the X-axis or Y-axis Properties dialog box,click the Labels tab.

2. To display labels for the ticks along the axis, click toselect Show Values.

3. In the Field list (if available), select the field that youwant to use to identify the ticks on the x-axis.Choose the field that most clearly describes therecords used in the chart. For more information, seeAbout the category field on page 342 .

4. In the Size list, type or select the size of the fontused for the labels.

5. In the Color list, select the color that you want touse for the font. To modify the color, click More. Tochange the font, click Selector. For moreinformation about the Selector, see Selecting a styleon page 354 .

6. In the Angle box, type the value representing thecounterclockwise rotation that you want to apply tothe label. In the list select the unit of angularmeasurement.

7. Click OK.

Opening the X-axis or Y-axisProperties dialog box

Dividers are used to mark the axis values.

1. In the Chart viewer toolbar, click the Selection Toolbutton.

2. Click either the axis, the axis heading, or the axisvalues.k

3. In the Chart viewer toolbar, click the Propertiesbutton.

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Displaying grid lines along the axis

1. On the X-axis or Y-axis Properties dialog box,click the Dividers tab.

2. Select Gridlines.3. To change the look of the line, select a style in the

Style box. If you want to create a style, click StyleSelector in the list (see Selecting a style on page 354).

4. Click Apply.

Displaying ticks

1. On the X-axis or Y-axis Properties dialog box,click the Dividers tab.

2. To display the ticks on the background, selectInside ticks.

3. To display the ticks on the axis but not on thebackground, select Outside ticks.

4. Click Apply.

Opening the Title or SubtitleProperties dialog box

You can design and position your title or subtitle in Titleor Subtitle Properties dialog boxes or you can modifythem directly in the Chart Viewer. As you make changesin the Chart Viewer, Focus updates the Title or SubtitleProperties dialog boxes.

1. In the Chart viewer toolbar, click the Selection Tool

button.2. Click the title or subtitle.3. In the Chart viewer toolbar, click the Properties

button.

Customizing the title or subtitle of thechart

1. In the Title box, type a word or phrase that youwant as a title or subtitle for your chart.

2. In the Size list, type or select the size of the font.3. In the Color list, select the color that you want to

use for the font. To modify the color, click More. Tochange the font, click Selector. For moreinformation about the Selector, see Selecting a styleon page 354 .

4. Under Placement, click to select the position of thetitle or subtitle in reference to the chart. To place theit manually in the viewer, drag the title or subtitlewhere you want it. The setting under Placement willautomatically change to Custom.

5. Click OK.

Opening the data labels properties

In the chart, the data is represented by a graphic such asa column or a line. In some cases it may be useful tolabel the graphic with one or several attribute values fromthe record. These labels that appear on the data in thechart are called data labels.

To display the data labels on the chart, see Designing thechart surround on page 341 .

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1. In the Chart viewer toolbar, click the Selection Toolbutton.

2. Click a data label.3. In the Chart viewer toolbar, click the Properties

button.

Customizing the data labels

1. If you want to include the description from thelegend in the label, select the Legend items box.

2. If you want to include the x-axis values in the label,select the X-data values box.

3. If you want to include the y-axis values in the label,select Y-data values box.

4. If you want to display the percent value of the data,select the Percentages box (only available for100% Stacked Column, 100% Stacked Bar, 100%Stacked Line, 100% Stacked Area, and Pie charts).

5. If you want to draw lines from the percent values tothe corresponding data, select Show leader lines(only available for 100% Stacked Column, 100%Stacked Bar, 100% Stacked Line, 100% StackedArea, and Pie charts).

6. In the Size list, type or select the size of the fontused for the labels.

7. In the Color list, select the color that you want touse for the font. To modify the color, click More. Tochange the font, click Selector. For moreinformation about the Selector, see Selecting a styleon page 354 .

8. Click OK.

Saving a chart

Charts are kept in memory as long as the project remainsopen, even if you close the Chart viewer. You can reopenan existing chart by using the Chart Manager (seeOpening or deleting a chart on page 348 ).

The settings for each chart that you create while theproject is open are saved in the project file (.gpr) whenyou save the project. The data itself, however, is notsaved with the chart. The chart only contains a referenceto the data. If you make changes to the layer#s attributes,the chart will reflect the changes in the data the next timeyou open it, but the design of the chart will remainunchanged. If you close the project without saving it, thecharts in memory are discarded along with any otherchanges in the project file.

You can also export your chart as a graphic in one ofseveral file formats. For more information, see Openingthe Export Map dialog box on page 407 .

Opening and deleting a chart

The settings for the charts that you create while theproject is open are kept in memory as long as the projectremains open, even if you close the Chart viewer. Bydefault the charts are listed in the Chart Manager in theorder that they were created.

When you save the project, only the settings for eachchart are saved in the project file (.gpr), not the dataitself. The chart only contains a reference to the data. Ifyou make changes to the layer#s attributes, the chart willreflect the changes in the data the next time you open it,

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but the design of the chart will remain unchanged. If youclose the project without saving it, the charts in memoryare deleted along with any other changes in the projectfile.

To display an existing chart

1. In the main menu of the Attribute Manager (seePerforming tasks in the Attribute Manager on page304 ), click Tools.

You can also click Layer in the main menu.

2. Click Charts, and then click Manage.3. Click the chart that you want to see.4. Click the View button.5. Click Close.

To sort the list in ascending or descending order

1. In the Chart Manager, click any of the tableheadings.

To delete a chart

1. In the main menu of the Attribute Manager (seePerforming tasks in the Attribute Manager on page304 ), click Tools.

or

In the Focus main menu, click Layer.

2. Click Charts, and then click Manage.

3. Click the chart that you want to delete.4. Click the Delete button.5. Click Close.

Digitizing vectors with peripheraldevicesFocus allows you to connect and use digitizing tabletsand GPS tools to create new data.

You can use a GPS tool to provide two services withinthe Focus environment: you can update the position ofthe cursor within an Area and you can use it as a datainput device for a vector layer. In either case, you musthave an Area layer that contains the appropriategeoreferencing information and you must have a workingconnection between your computer and your GPSreceiver. (See Setting up a GPS receiver on page 111 )

When a digitizing tablet is connected to the computer,you can digitize features from a paper map and use theresulting vector data in your projects. A digitizing tabletconsists of a electronic platform (a tablet) and a pointingdevice (a puck). To set up the tablet to work with Focus,see Setting up a digitizing tablet using Wintab on page110 .

Registering a digitizing tablet

Once you connect a digitizing tablet to the computer andtape the map to the tablet, you are ready to register amap. Registering the map means that you establish areference frame between the tablet, the paper map, and

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your project.

The reference frame is established by collecting points onthe tablet and collecting the same points in the view paneso that Focus can correlate the positions. You can collectthe points on each of the four corners of the map or oneasily identified features as long as the points are welldistributed over the map.

With a minimum of four points, Focus can estimate thedifference between the coordinates that you entered inthe view pane and the coordinates from the tablet. Thedifference, called an error estimate, reflects the accuracyof the registration between the tablet and Focus.

1. From the Maps tree, click a layer.2. From the Tools menu, click Digitizing Tablet and

then click Register.3. In the Register Tablet dialog box, click one of the

following buttons:• Active Area: uses the same georeferencing

as the one defined in New Area• Active Layer: uses the same georeferencing

as one defined in the current layer4. In the Tie Coordinate Type list box, choose one of

the following options:• Geocoded: enters the coordinates in

georeferenced units• Geographic: uses Longitude/Latitude units

5. On the tablet, move the crosshairs of the puck to afeature and press the button to transfer the tabletcoordinates to the Tie-Down table.

6. In the Register Tablet dialog box, type thecoordinates of the same feature in the TieCoordinate X and Tie Coordinate Y columns, or

you can click to select the feature in the view paneand press Enter to transfer the coordinates to theTie-Down table.

7. Repeat step 5 and step 6 to complete theregistration.

If you want to add more points to the table, click theAdd button. To remove a point from the table, clickthe point, and click the Remove button. To removeall the points in the table, click Clear All.

8. Click OK.

Importing and exporting tabletregistration

Once you register the map on the tablet, you can savethe registration. The registration remains valid as long asthe map is not moved or removed from the tablet. (SeeRegistering a digitizing tablet on page 349 )

To export a registration

• From the Register Tablet dialog box, click Export.

To import a registration

• From the Register Tablet dialog box, click Import.

Using a digitizing tablet

Once you register the map on the tablet, you can use thepuck to digitize features from the map. (See Registering a

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digitizing tablet on page 349 )

You can assign the puck buttons to perform a variety ofactions. (See Assigning text actions and modifiers onpage 111 )

You can use the puck with the following tools:• Adding points to an active layer on page 303• Selecting a single shape on page 321• Editing vectors using the vector editing tools on

page 323

To start digitizing

1. From the Maps tree, click the layer that you want tocontain the vectors.

2. From the Tools menu, click Digitizing Tablet andthen click Start Digitizing.

3. Click the tool that you want to use or press the puckbutton assigned to the action that you want toperform.

For example, if you want to digitize a line, you canclick Line in the New Shapes list on the toolbar orclick the puck button that you assigned to NewLine.

4. Use the puck to perform the action that you want.

For example, use the puck to digitize a road on themap.

To stop digitizing

• From the Tools menu, click Digitizing Tablet andthen click Stop Digitizing.

Using the GPS tool

Before a GPS tool can be accessed, a connection mustbe set. A GPS receiver connection is made through theFocus Options dialog box.

With a Focus Area open and the GPS receiverconnection set, a GPS tool can be used. The GPS tool islaunched through the GPS Tool dialog box.

1. Ensure a GPS connection has been established.2. Open an Area containing appropriate

georeferencing information.

The Area georeferencing bounds should correspondto the area where a GPS receiver is located. If aGPS receiver is outside of these bounds you cannotupdate the cursor or collect vectors. In such a case,the vector segment ends and a new segment mustbe started.

3. From the Tools menu, click GPS Tool.

When the GPS tool is active, you can update the viewpane cursor position or add vector data to an Area in aproject.

Inputting vector point data using aGPS receiver

1. Ensure a GPS connection has been established.2. From the Maps tree, right-click the Area and click

New Vector Layer.

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3. In the New Vector Layer dialog box, enable thePoint option and click OK.

4. In the Maps tree, select the new point layer.5. On the Editing toolbar, click the New Shapes arrow

and choose Points.6. From the Tools menu, click GPS Tool.7. In the GPS Tool dialog box, click one of the

following buttons:• Capture Stream: updates the new point layer

with a point determined by the location of theGPS receiver

• Capture Point: adds new points to the vectorlayer at a specified stream interval. You cancontinue to collect points by repeatedlyclicking the button.

8. Click Finish.

Inputting vector line or polygon datausing the GPS receiver

1. Ensure the GPS Tool dialog box is open.2. From the Maps tree, right-click the Area layer and

click New Vector Layer.3. In the New Vector Layer dialog box, enable one of

the following options in the Layer Type area:• Line• Topological Line• Polygon• Topological Polygon

4. Click OK.5. In the Maps tree, select the new layer.6. In the GPS Tool dialog box, click one of the

following buttons:

• Capture Stream: adds a new vertex to thevector layer at the specified stream interval.New vertices are added to the line or polygonuntil you click Finish.

• Capture Point: adds only the initial vertex tothe line or polygon layer. You can continue tocollect vertices for the line or polygon witheach click of the button.

Understanding representationRepresentation determines the appearance of shapes.Focus applies a default representation to shapes on avector layer that is not linked to a Representation StyleTable (RST). You can continue using the default, create anew RST, or import an existing RST.

An RST is a look-up table (LUT) that contains a key andthe style associated to that key. The key or the style canalso be referred to as a REPCode. The key links the stylein the RST to the shape on the layer. Each layer can linkto only one RST, but you can link an RST to many layers.

Keys can be added as attributes for shapes, such as inthe REPCode field, or you can use an existing attributeas the key. When an RST is linked to a layer, Focusidentifies the attributes used as keys in the layer andsearches for the corresponding keys in the RST. When amatch is found, the associated style is applied to theshape in the layer.

For example, you can associate an RST to the attributesin a field called roadtype. In the roadtype field, you havea variety of road types such as interstates, highways, andstreets. In the RST, the key is the road type with which

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you have styles associated. When a layer is linked to theRST, the shapes are assigned the style according to theirkey.

A style is composed of one or more parts. Each part hasa primitive with a priority. Primitives are the buildingblocks of the style. Each primitive is based on a point,line, or polygon pattern that is designed according to anumber of parameters, such as color. The prioritydetermines which part is placed in front of the other partsin the style. You can control the order by assigning thepart a priority number. Parts with a higher number appearin front of parts with lower numbered priority.

Types of representation style tablesFocus uses three types of RSTs: Default, Direct, andIndirect.

Default RST:

Is controlled by Focus and is applied to vector layers inthe absence of any other RST.

Direct RSTs:

Is also called Embedded Representation, because thestyle is contained in a layer itself. You can create a DirectRST when you change the appearance of the shapesdirectly in the view pane using tools in the Displaytoolbar. Direct RSTs are only available for .pix vectorlayers.

When you change the appearance of shapes in the viewpane, Focus creates an RST using the ShapeIds as thekeys. The Direct RST is saved directly in a .pix file.

Indirect RST:

Is a separate file (.rst) that contains an RST. You can linkan Indirect RST to one or more layers. In previousversions of Focus, the Indirect RST could also have a.gtd extension. The .gtd file is still compatible and can beedited and resaved as a .gtd file. You can also convert anIndirect RST into a Direct RST by embedding it in thelayer through its Properties dialog box.

You can build an Indirect RST as System-linked orUser-linked.

System-linked RST:

Is based on an attribute in a layer. To generate the RST,select an attribute from the layer to become the key;Focus creates styles for each key based on the style thatyou design. Focus automatically links the System-linkedRST through the key.

User-linked RST:

Often called a master RST, is built independently from alayer. To build the RST, you define the keys andmanually create styles associated to the keys. Once youbuild the RST, you link the layers to the RST. The keys inthe RST can match an existing attribute in the layer oryou can add the keys in a field in the layer.

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Generating an indirect representationstyle table

To generate a System-linked RST, you select an attributefrom the layer to become the key, and Focus createsstyles for each key, based on the style that you design.Focus automatically links the System-linked RST throughthe key.

1. From the Maps tree, right-click a layer and clickRepresentation Editor.

2. Choose an attribute that you want associated with astyle from the Attribute list box.

3. Click the Generating tab and choose one of thefollowing options from the Method list box

• Unique Values: assigns a style to each shapeaccording to its value. Each value receives itsown style.

• Ranged Values: assigns a style to all theshapes within a range of numeric values. Eachrange receives its own style. Choose the typeof range that you want to use from the Typelist. Shapes containing a NoData value aredisplayed using the Default RST. Enter anumber of ranges by which you want to dividethe values in the Number of classes spin box.

• The minimum and maximum values for theattribute automatically display. If you want torestrict the range available for division, enter aminimum and maximum values in the Min andMax spin boxes.

4. Enable one of the following options:• Copy styles from: uses existing styles as the

basis for the representation. Choose an RSTfrom the File list box.

• Generate new styles # creates new styles.Choose a style from the Based on list box.For more information about defining a newstyle, see Selecting a style on page 354 .

• If you want to assign various colors to thestyles, enable the Vary color check box andchoose a color scheme.

• If you want to assign various sizes to thepoints or lines, enable the Vary size checkbox. Enter the size in the From and By spinboxes. By default, the units is in millimeters.

5. Click Update Styles.6. Click OK.

Editing the representation styles

1. From the Maps tree, right-click a layer and clickRepresentation Editor.

2. Under the Style column, select a style.3. Click the Edit Style tab.4. Make changes to the color and outline width of the

style. (See Changing style appearance on page 355 )5. Make any changes to the parts of the style. (See

Changing style parts on page 355 )

Selecting a style

1. From the Files list in the Style Selector dialog box,select a representation.

If a file is not available, click Browse and select a

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file.

2. Click a tab containing the style type that you want.3. Select a style.4. Click More.5. Make any changes to the color and outline width of

the style. (See Changing style appearance on page 355)

6. Make any changes to the parts of the style. (SeeChanging style parts on page 355 )

7. Click OK.

Changing style appearance

1. From the Style Selector dialog box, click Simple.2. Click the Color arrow next to the part you want to

change and choose a color from the palette.3. For the following elements, do the following:

• Points: enter the factor that you want to use inthe Scale box. Scale increases the proportionof the original symbol.

• Lines: enter a thickness and choose a unit ofmeasurement from the Width list box.

• Polygons: enter a thickness and choose aunit of measurement from the Outline Widthlist box.

• Text: enter a font size and choose a unit ofmeasurement from the Size list box.

4. Click OK.

Changing style parts

1. From the Style Selector dialog box, click

Advanced.2. Choose a part that you want to change from the

Part list.

If you want to add or remove a part, click the Add orRemove button.

3. Enter a number that determines the priority order ofthe part from the Priority spin box. The highestnumber appears in front.

4. Choose a type from the Primitive list box. EachPrimitive type contains a list of parameters.

5. For each parameter, change any changes to valuesin the Values column.

6. Click OK.

Using an attribute as part of the style

An attribute is usually selected from a layer to becomethe key, and Focus creates styles for each key based onthe style that you design. You can, however, use otherattributes from a layer to be part of the style for theshapes.

To use an attribute as part of the style, you must create amulti-part style (see Editing the representation styles onpage 354 ). You assign one of the parts of the style to anattribute through the Advanced Attributes dialog box.

1. Create a multi-part style.2. From the Style Selector dialog box, choose a part

from the Part list box.3. Choose Vector - Text from the Primitive list box.4. Set any other parameters.5. Click OK.6. In the Representation Editor dialog box, click

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Advanced Attributes.7. In the Text Attribute list, select a field containing

the text that you want to incorporate into the style.8. Click OK.

Opening the Set Style Attribute dialogbox

1. Use a Selection tool to select a shape.2. From the Edit menu, click Set Style Attribute.3. Click a style.4. Click OK.

Setting the style attribute

1. In the Set Style Attribute box, type the code orname of the style.

2. Click the Find First button.3. If the result is not the style that you are looking for,

click Find Next until you find the style.4. To limit the styles to a particular type, choose a type

in the Graphical Representation list.5. When the style is selected, click OK.

Selecting a symbol

1. From the Symbol Selector dialog box, choose asymbol file from the Files list box.

2. In the gallery, select a symbol.

If you want to preview the symbol and the previewwindow is not displayed, click More.

3. Click OK.

Labelling shapes

A label is a string of characters placed in close proximityto a shape. You can use labels to display informationabout the shapes and clarify the subject of the layer. TheLabel Tool uses an attribute from the layer as a label forthe shape. You can create labels for vector, grayscale,and pseudocolor layers that contain attributes.

Because the automatic placement of labels may beinadequate, you can make individual changes to thelabels by using the Selection Tools in the Editing toolbar.You can change the style of the labels individually usingthe tools in the Display toolbar. Any changes to thecharacters used in the label are updated automatically inthe view pane and the Attribute table.

If you make specific changes to individual labels with theSelection Tools or the Display tools and then use theLabel Tool for more changes, specific changes may bereplaced by the options set in the Label Tool.

1. From the Maps tree, right-click a layer and clickProperties.

2. In the Properties dialog box, click the Labels tab.3. See Managing the labels on page 356 .

Managing the labels

The Label tab on the layer#s Properties dialog boxcontains the label sets associated with that layer. Formore information about labels see Labelling Shapes on

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page 356 and Managing data properties on page 35 .

If you are making modifications to individual labels withthe intention of printing a map, switch Focus to Map Viewmode before beginning your edits. To switch to Map Viewmode, in the main menu click View and then Map ViewMode.

1. To display the labels in the View Pane, click in theVisible column beside the label set that you want toshow. To hide the labels, click to clear the checkmark.

2. To make the labels selectable in the View Pane,click in the Selectable column beside the label setthat you want.

3. To add a new label set, click Add New. For moreinformation, see Adding labels to a layer on page 357.

4. To modify existing labels, click Modify. For moreinformation, see Changing labels on page 357 .

5. To remove a label set, select the layer under LabelName and click Delete.

6. Click OK.

Adding labels to a layer

1. From the Properties dialog box, click the Label taband click Add New.

2. Set options for the labels. (See Defining the designand layout for labels on page 358 )

3. Design the look for the labels. (See Setting labelrepresentation on page 357 )

4. Click OK.

Setting label representation

Representation controls the appearance of all labels on alayer.

1. From the Label Tool dialog box, click the Stylebutton and create a style for the text (see Selectinga style on page 354 ).

2. In the Color box, you can change the color of thefont that you selected in the Style Selector.

3. In the Size box, you can change the size of the fontand select the unit of measure that you want.

4. Click OK.

Changing labels

If you are making modifications to individual labels withthe intention of printing a map, switch the Focus viewpane to Map View mode by clicking the Map View Modebutton before begining your edits.

1. From the Maps tree, right-click a layer and clickProperties.

2. From the Properties dialog box, click the Labelstab.

3. Select the label you want to change and clickModify.

If you want to change the representation for thelabels, see Setting label representation on page 357.

If you want to change the options for the labels, seeDefining the design and layout for labels on page 358

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.

4. Click OK.

Defining the design and layout forlabelsThe Label Tool provides the general look and layout forlabels. It also follows some of the formatting optionsdetermined for the field in the Attribute Manager. Forexample, if the field in the attribute table used for thelabels is defined as having two decimal places, the labelswill have two decimal places.

You can make individual changes to the labels by usingthe Selection Tools in the Editing toolbar. You canchange the style of the labels individually using the toolsin the Display toolbar.

If you are making modifications to individual labels withthe intention of printing a map, switch the focus viewpane to Map View mode by clicking the Map View Modebutton before begining your edits.

The layer type determines which options are available forlabels. For example, an unstructured layer can containpoints, lines, and polygons, and all options are available.

See also:

Defining which attribute to use for the label on page 358

Setting the position for point layer labels on page 359

Setting the position for line layer labels on page 359

Setting the position for polygon and raster layer labels onpage 360

Defining which attribute to use for thelabel

1. From the Label Tool dialog box, click the Generaltab.

2. Choose an attribute from the Attribute list box.3. Type a name for the labels in the Label set name

box.4. To label only the shapes that you have selected in

the layer, select Label selected shapes only.Clear the check mark to label all the shapes in thelayer.

5. To clear existing labels and relabel the shapes inthe layer, select Overwrite existing labels. Clearthe check mark to label only the unlabelled shapes.If you selected Label selected shapes only in theprevious step, only the shapes that you haveselected are relabeled.

6. To display #NoData# as a label for recordscontaining null values or lacking data, selectInclude NoData. Clear the check mark to hide theNoData labels.

7. Click OK.

See also

Setting label representation on page 357

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Setting the position for point layer labels on page 359

Setting the position for line layer labels on page 359

Setting the position for polygon and raster layer labels onpage 360

Setting the position for point layerlabels

The Offset determines the location of the label's anchorrelative to the point, not the alignment of the label's textrelative to the label's anchor. To change the alignment ofthe text, change its style (see Setting label representationon page 357 ).

1. In the Label Tool dialog box, click the PointOptions tab.

2. In the Vertical list, type or select the valuerepresenting the vertical position of the label relativeto the point. In the list, select the measurement unit.

3. In the Horizontal list, type or select the valuerepresenting the horizontal position of the labelrelative to the point.

4. Select Keep equal to keep the vertical andhorizontal offset the same distance. Clear the checkmark to keep the offsets independent of each other.

See also

Setting label representation on page 357

Defining which attribute to use for the label on page 358

Setting the position for line layer labels on page 359

Setting the position for polygon and raster layer labels onpage 360

Setting the position for line layerlabels

The Position and Offset determine the location of thelabel's anchor relative to the line, not the alignment of thelabel's text relative to the label's anchor. To change thealignment of the text, change its style (see Setting labelrepresentation on page 357 ).

1. In the Label Tool dialog box, click the LineOptions tab.

2. Under Vertical in the Position list, select whetheryou want the label to appear above or below theline.

3. In the Offset list, type or select the valuerepresenting the space between the line and thelabel. In the list, select the measurement unit.

4. Under Horizontal in the Position list, selectwhether you want the label to appear to the left,right, or in the middle of the line.

5. In the Offset list, type or select a value to adjust theposition of the label. In the list, select themeasurement unit.

See also

Setting label representation on page 357

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Defining which attribute to use for the label on page 358

Setting the position for point layer labels on page 359

Setting the position for polygon and raster layer labels onpage 360

Setting the position for polygon andraster layer labels

The Offset determines the location of the label's anchorrelative to the centroid, not the alignment of the label'stext relative to the label's anchor. To change thealignment of the text, change its style (see Setting labelrepresentation on page 357 ).

1. In the Label Tool dialog box, click the AreaOptions tab.

2. In the Vertical list, type or select the valuerepresenting the vertical offset of the label relativeto the centroid of the area. In the list, select themeasurement unit.

3. In the Horizontal list, type or select the valuerepresenting the horizontal offset of the labelrelative to the centroid of the area.

4. Select Keep equal to keep the vertical andhorizontal offset the same distance. Clear the checkmark to keep the offsets independent of each other.

See also:

Setting label representation on page 357

Defining which attribute to use for the label on page 358

Setting the position for point layer labels on page 359

Setting the position for line layer labels on page 359

Designing a symbolThe Symbol Editor contains tools to create or editsymbols. A symbol is composed of one or more parts. Asymbol can be a single design or a compilation ofoverlapping designs and are stored in files with a .symextension. Symbol files can be used in one or moreRSTs.

See also:

Understanding the symbol working area on page 360

Creating a symbol on page 361

Creating a multi-part symbol on page 361

Selecting a symbol from the symbol file on page 362

Setting symbol representation on page 362

Editing the symbol RST on page 362

Understanding the symbol workingarea

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The working area of the Symbol Editor equals four unitssquare in the map. If you draw a symbol that occupiesthe whole working area, it will be two units high on themap. The bounding box is the blue box that appearsinside the working area. This box is one unit square onthe map. The measurement unit is defined in the RSTProperties dialog box.

Creating a symbol

1. From the Maps tree, right-click a layer and clickRepresentation Editor.

2. In the tree, right-click Symbol Files and clickNewSymbol.

3. Double-click NewSymbol.sym.4. In Symbol Editor, click Symbol and then click

Create Symbol.5. In the Attributes dialog box, type a number that will

represent the symbol in the New box below CurrentSymbolId.

6. Type a label for the symbol in the New box belowDescription.

7. Click OK.8. Draw a symbol. Use the tools explained in Adding

points to an active layer on page 303 , Selecting asingle shape on page 321 , and Editing vectorsusing the vector editing tools on page 323 .

9. From the File menu, click Save Symbol.

Creating a multi-part symbol

If you want your symbol to contain different colors, you

must divide your design into parts. Each part of thesymbol contains the design elements of one color. Youcan use the Symbol Editor to determine the form andstructure of the symbol, but the parameters of thesymbol, such as color and scale, are determined in theRepresentation Editor. (See Editing the representationstyles on page 354 )

You can rename and save a symbol file to a new locationwith the symbol file Save As dialog box. To open thesymbol file Save As dialog box, right-click a symbol layerin the Maps tree and click Save As. (See About thesymbol file Save As dialog box on page 362 )

1. Create a design. (See Designing a symbol on page360 )

2. From the Symbol menu in the Symbol Editor, clickDuplicate Symbol.

3. In the Attributes dialog box, type a number that willrepresent the symbol in the New box below CurrentSymbolId.

4. Type a label for the symbol in the New box belowDescription.

5. Click OK.6. Keep the shapes that you want and use the

Selection tools to delete all the other shapes thatare destined for another color.

7. Change the style of the remaining shapes. (SeeSetting symbol representation on page 362 )

8. Select the source symbol (See Selecting a symbolfrom the symbol file on page 362 ) and repeat foreach part of the symbol.

9. From the File menu, click Save Symbol.

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Selecting a symbol from the symbolfile

The Select Symbol dialog box lists all the symbols in thesymbol file. You can select individual symbols from thesymbol file.

1. From the Symbol menu in the Symbol Editor, clickSelect Symbol.

2. Click a symbol.3. Click OK.

Setting symbol representation

1. Use a Selection tool to select a shape.2. From the Edit menu in the Symbol Editor, click Set

Style Attribute.3. Click a style.4. Click OK.

Editing the symbol RST

The Symbol RST controls the width of the lines, the sizeof the text, and the font.

• From the Tools menu in the Symbol Editor, clickEdit RST.

If you want to change a style, select it and makeany modifications.

About the symbol file Save As dialogboxThe symbol file Save As panel lets you rename and savea symbol file in the Maps tree to a new location.

Input

The Input area shows the name and location of thecurrent symbol file.

Symbols:

Reports the name and location of a symbol file.

Output

Lets you choose a different symbol file, select a formatfor the output, and rename a symbol file.

File:

Lets you choose a symbol file from the current data.

Browse:

Opens a File Selector dialog box, where you can select adifferent location for the output.

Format:

Lets you select a format for your output.

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Description:

Lets you enter a new name for the output symbol file.

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Chapter 9Saving a project fileWhen you prepare data for a publication, it isrecommended that you organize the information in aFocus project file. (See Working with project files on page31 )

• From the File menu, click Save Project.

Renaming a map

1. In the Maps tree, right-click a map and clickRename.

2. Type a name for the map and press Enter.

Starting a new map

Focus must be in Map View mode in order to work onMap projects. By default, when you open data files,Focus is in Area View mode.

1. From the View menu, click Map View Mode.2. In the Maps tree, click a map element to select and

change it.

If you want to open the Properties dialog box for aselected item, double-click it in the Maps tree.

You can create a Map by either clicking the New Mapbutton on the Maps toolbar or by right-clicking the areaunder the Maps tree and clicking New Map.

When you create a new Map, Focus automatically placesan empty frame in the view pane that represents thepaper on which the Map is printed. Maps have severalproperties that you can change with the Map Propertiesdialog box.

Working with map properties

• From the Maps tree, right-click a map and clickProperties.

You can change the Map description by typing in theName box. When you click Apply, the text appears in theMaps tree as the Map name.

You can name Maps, Areas, and layers the same wayyou would rename a file in other Windows applications.Click the file name in the Maps tree and type a name forthe Map or layer. You can also right-click a file name, andclick Rename.

Changing the paper size by dragginga resize handle

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By default, new Maps have a paper size of 215.9 x 279.4millimetres (8.5 x 11 inches). You can change the papersize to several standard sizes in the Map Propertiesdialog box. You can also set a custom paper size bydragging the Map handles in the view pane.

1. On the ViewMap toolbar, click the Map Viewbutton.

2. In the Maps tree, select a Map.3. In the view pane, drag a resize handle.

Drag a map handle in the view pane to resize a mapsheet.

Changing the paper size from the MapProperties dialog box

1. Double-click a Map.2. In the Map Properties dialog box, click the Page

Setup tab.3. Enable an orientation option.4. Select a standard paper size from the Page Size list

box.

If you want to use a custom paper size, chooseCustom and enter the dimensions in the Width andHeight spin boxes. Choose a unit of measurementfrom the list box.

5. Click OK.

Working with areas

Areas hold the file boundaries for image (raster) andvector layers. They can contain several layers for thesame geographical region, and you can have as manyAreas in a project as you want. Each Area has a uniquegeoreferencing system. When you add a layer, it isautomatically georeferenced and scaled to the Area.

You can add an Area to a Map and place layers within it.The new layers hold vector and raster data, such aspolygons, points, and segments that you need for theMap. Surrounds and indices are held in similar areas, butyou can work with these elements independently. (SeeWorking with surrounds on page 371 )

You can adjust the bounds of an Area independently froma Map. When you add an Area, files are shown below theMap in the Maps tree. Vector and raster layers containedwithin the Area are shown below it. If you resize or movean Area so that part of it lies outside the extents of theMap (paper), the Area appears red in the Maps tree.

• From the Maps tree, right-click a Map and clickNew Area.

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Scaling an area

In cartography, scale is the ratio of the distance betweentwo points on a Map, and the actual distance between thesame two points on the Earth#s surface.

Scales can be represented as a

• Ratio or representative fraction (RF), such as1:50,000 or 1/50,000, which means that one unit ofmeasurement on the Map equals 50,000 of thesame units on the Earth's surface.

• Graphic scale, usually a straight line on whichdistances (most often in kilometers or miles) havebeen marked off.

• Scale statement, such as 1 cm = 100 km. Thisscale statement means one centimetre on the Maprepresents 100 kilometers on the Earth's surface.

New Areas are automatically scaled to the best fit for thedimensions of a Map. For example, Focus sets the areascale for a standard 8.5 x 11 page to a scale factor of1:20000 by default. A new Area contains no raster orvector data. When you add new data, Focusautomatically scales it to the area scale.

When Focus is in Map mode, you can click on an area inthe Maps tree. you can modify the area in the view paneby dragging one of the eight handles in the viewer.

Note: With an area, the middle handles crop the image.The corner handles rescale it.

Use the area handles in the view pane to rescale, crop,or enlarge an Area.

1. From the Maps tree, double-click an Area.2. In the Area Properties dialog box, click the

General tab.3. Choose a scale from the Scale list box.

If you want to create a different scale, chooseCustom and enter a value in the Scale box.

4. Click OK.

When you change the scale in the Area or Math ModelArea Properties dialog boxes, it becomes the scale for allnew layers added to that Area.

Rescaling an area

When you rescale data in the view pane, you extend orcompress both the horizontal and vertical planes of thedata. The aspect ratio stays the same. All features in aselected Area are enlarged or reduced by a factorcorresponding to the ratio of rescaling. You can changethe Scale Factor.

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You can perform rescaling operations in both Map orArea view mode.

1. Ensure Focus is in Map view mode.2. In in the Maps tree, select an Area.3. Drag a corner of the Area to a new position.

Note: Surround areas can be resized and rescaled.However, scale bars and neatline will not be affected byrescaling.

The paper range and the scale factor are adjustedautomatically when you rescale a selected area, but thegeoreferenced information remains the same. To viewthe new scale values, open the Area Properties dialogbox.

The paper range and the geographic range are adjustedautomatically when you resize a selected area but theappearance of the existing layers does not change.

Setting area properties

An Area is a rectangular frame that holds layers of dataand serves as a window into a location on the Earth. Itsproperties determine how the layers of data aredisplayed.

The features available on the Layout tab on the AreaProperties dialog box determine the position of the Areaon the Map. The Map represents the sheet of paper onwhich the project is printed. You can have several Areason a Map and each Area retains its own projection and

georeferencing information.

Understanding Areas

• From the Maps tree, right-click a New Area andclick Properties.

Setting area properties1. From the Area Properties dialog box, click the

General tab.

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2. Type a name for the Area in the Name box.

If you want to have a border around the Area,enable the Show Outline check box.

3. Choose a scale to determine the ratio of thedistance between two points from the Scale list box.

If you want to use a custom scale, choose Customand type the ratio value. (See also Scaling an areaon page 367 )

4. Click the Layout tab.5. Enter a value used to rescale the representation

displayed on the Map in the Scale Factor spin box.

For example, if the symbol is 1 millimeter wide, ascale factor of 5 will display the symbol as 5millimeters wide on the Map.

6. Enter a value representing the priority of the Arearelative to other Areas in the Priority spin box.

Areas with higher priority levels (larger numbers)mask overlapping Areas with lower priorities. (SeeChanging the layer priority on page 28 )

7. In the Position area, enter a value representing thehorizontal distance from the left edge of the Map inthe Left spin box and choose a unit ofmeasurement for the position and size.

8. Enter a value representing the vertical distance fromthe bottom edge of the Map in the Bottom box.

9. In the Size area, enter a value for the Area as itappears on the Map in the Width and Height spinboxes.

If you want to automatically adjust the extents of theArea to accommodate the data, enable the

Automatic Resize check box.

10. Click the Projection/Extents tab.11. Enable one of the following options in the Bounds

list box:• Geocoded: displays the bounds in

georeferenced units• Geographic: displays Longitude/Latitude units

12. Enter the coordinates of the upper-left corner andlower-right corner of the Area in the appropriateboxes.

13. Enter a value for an angle of rotation in theRotation box and choose a unit of measurement.

If you want to limit processes to a subset of thedata, click Define Clip Region. Enable the Enablecheck box to activate the clip region.

14. Click OK.

Opening the Math Model AreaProperties dialog box

A Math Model Area is similar to an Area, except theprojection is determined by a math model segmentcontained in the image file. A Math Model Area is arectangular frame that holds a layer containing a rawimage displayed without correction, but accurate groundcoordinates are calculated for each pixel using the pixeland line coordinates, the math model, and the digitalelevation model (DEM) or an approximate elevation valuethat you provide. For more information, see Using a mathmodel with images on page 40 .

You cannot open other images in a Math Model Area,

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because the math model is computed for a specificimage. You can, however, add geocoded vector layers tothe Math Model Area. Due to the special nature of a MathModel Area, surround elements, such as grids and northarrows are disabled, and the extents are determined bythe file.

• From the Maps tree, right-click a Math Model Areaand click Properties.

Setting Math Model Area properties

A Math Model Area is similar to an Area, except theprojection is determined by a math model segmentcontained in the image file. A Math Model Area is arectangular frame that holds a layer containing a rawimage displayed without correction, but accurate groundcoordinates are calculated for each pixel using the pixeland line coordinates, the math model, and the digitalelevation model (DEM) or an approximate elevation valuethat you provide. For more information, see Using a mathmodel with images on page 40 .

1. From the Math Model Area Properties dialog box,click the General tab.

2. Type a name for the Math Model Area in the Namebox.

If you want to have a border around the Math ModelArea, enable the Show Outline check box.

3. Choose a scale to determine the ratio of thedistance between two points in the Math ModelArea from the Scale list box.

If you want to use a custom scale, choose Customand type a value ratio. (See also Scaling an area onpage 367 )

4. Click the Layout tab.5. Enter a value used to rescale the representation

displayed on the Map in the Scale Factor spin box.

For example, if the symbol is 1 millimeter wide, ascale factor of 5 will display the symbol as 5millimeters wide on the Map.

6. Enter a value representing the priority of the MathModel Area relative to other Areas in the Priorityspin box.

Areas with higher priority levels (larger numbers)mask overlapping Areas with lower priorities. (SeeChanging the layer priority on page 28 )

7. In the Position area, enter a value representing thehorizontal distance from the left edge of the Map inthe Left spin box and choose a unit ofmeasurement for the position and size.

8. Enter a value representing the vertical distance fromthe bottom edge of the Map in the Bottom box.

9. Click the Projection/Extents tab.10. Enable one of the following options in the Bounds

list box:

Geocoded: displays the bounds in georeferencedunits

Geographic: displays Longitude/Latitude units

If you want to limit processes to a subset of thedata, click Define Clip Region. Enable the Enable

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check box to activate the clip region.

11. Click OK.

Working with surroundsA surround is a collection of graphical elements that givesmeaning or clarifies the meaning of geographicalinformation displayed in a Map. It puts the data intocontext that can be analysed, organized, andcommunicated effectively.

Focus provides the following surround elements:

• Neatline: a visible or invisible line marking theboundary around the Area beyond which no data isdisplayed.

• Border: a decorative frame around the Area. It isdrawn behind the Area and can be used as abackground.

• Grid: a pattern of regularly-spaced lines, usuallyused to indicate coordinates or used as dividers.

• Legend: a table listing and describing the symbolsand elements in the Area.

• Picture: a graphic such as an image or logo thatyou place on a Map.

• North Arrow: a graphic used to indicate thedirection of True North, Magnetic North, or GridNorth in relation to an Area.

• Scale bar: a graphical representation of the ratiobetween a distance in the Area and the actualdistance on the ground.

• Title: a name or phrase given to identify the Area.• Paragraph: a block of text, such as an explanatory

paragraph, that is placed on the Map.

Surround elements are positioned relative to the neatlineof the Area. If an Area does not contain a neatline, thepositioning is based on the Area extents. Any surroundelement, except for the neatline, can appear more thanonce in an Area. For example, if you want to show twodifferent scales in your map, such as one in kilometersand the other in miles, you can create two scale bars.

You can modify the look of the surround elements andsave those settings as a Quick Style, which can beapplied to the same type of surround element in theproject. For more information, see Selecting an existingquick style on page 397 .

Creating a surround

The surround elements are displayed in the Maps tree forthe Area to which they are associated. If you place asurround element so that part of it lies outside theboundaries of the Map, it appears red in the Maps tree.For more information about surrounds, see Working withsurrounds on page 371 .

1. From the View menu, click Map View Mode.2. In the Maps tree, right-click an Area and click

Surround.3. In the Surround dialog box, click a box next to any

element you want to use in the Map.

A check mark next to an element indicates it isselected.

4. Choose a style for a selected element from theSelect a QuickStyle list.

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If you want to create a new style, click Propertiesand follow Creating a custom quick style on page 397.

5. Click OK.

Setting a default surround element

1. From the Surround dialog box, click a box next toany element you want to use in the Map.

A check mark next to an element indicates it isselected.

2. Click Preferred surround.

Setting a default quick style

1. From the Surround dialog box, click a box next toany element you want to use in the Map.

A check mark next to an element indicates it isselected.

2. Choose a style for a selected element from theSelect a QuickStyle list.

3. Click Set as Default.

Setting surround element properties

You can change the look and position of a surroundelement through the Properties dialog box.

• From the Maps tree, right-click a surround element

and click Properties.

About neatlinesA neatline is a line around an Area that separates datafrom the rest of the surround. It is a line marking theboundary around the Area beyond which no data isdisplayed. Unlike the other surround elements, theneatline can only be used once in each Area. Theneatline also serves as the frame of reference forpositioning other surround elements.

To add a neatline to an Area, see Creating a surround onpage 371 . To open the Neatline Properties dialog box,see Setting surround element properties on page 372 .

The look of a neatline is determined by its:

• General properties (see Setting the position of aneatline in relation to an area on page 372 )

• Position (see Setting the updating behavior on page 395)

• Quick Style (see Selecting an existing quick style onpage 397 )

Setting the position of a neatline inrelation to an area

A neatline separates data from the rest of the surround.For more information, see About neatlines on page 372 .You can set the position of the neatline in relation to theboundary of the Area or according to specificmeasurements.

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1. From the Maps tree, right-click a neatline and clickProperties.

2. In the Neatline Properties dialog box, click theGeneral tab.

3. Click the Style button and create a style for the line(see Selecting a style on page 354 ).

4. In the Distance From Area area, enter a valuerepresenting the distance from the left neatline tothe Area in the Left spin box and choose a unit ofmeasurement from the list box.

If you want to keep the distance between theneatline and the Area the same on all sides, enablethe Keep equal check box and go to step 8.

5. Enter a value representing the distance from theright neatline to the Area in the Right spin box.

6. Enter a value representing the distance from the topneatline to the Area in the Top spin box.

7. Enter a value representing the distance from thebottom neatline to the Area in the Bottom spin box.

8. Click OK.

Setting specific extents for a neatline

Instead of using the extents of an Area as the basis of aneatline position, you can define specific coordinates.The X values are measured from left side of the Map(paper) and the Y values are measured from the bottomof the Map.

1. In the Neatline Properties window, click Advanced(see Setting specific extents for a neatline on page373 ).

2. In the Neatline Advanced Properties dialog box,enable one of the following options:

• Paper: bases extents on paper measurements• Georeferenced: bases extents on a

geographic coordinate system3. Enter a value measured from the left edge of the

Map to the lower left corner of the neatline in the Xmin spin box and choose a unit of measurementfrom the list box.

4. Enter a value measured from the left edge of theMap to the lower right corner of the neatline in the Xmax spin box.

5. Enter a value measured from the bottom edge ofthe Map to the lower left corner of the neatline in theY min spin box.

6. Enter a value measured from the bottom edge ofthe Map to the upper left corner of the neatline inthe Y max spin box.

7. Click OK.

About bordersA border is a decorative frame that surrounds a Map. Youcan build a border as simple or as complex as you want.

To add a border to an area, see Creating a surround onpage 371 . To open the Border Properties dialog box, seeSetting surround element properties on page 372 .

The look of a border is determined by its:

• General properties (see Changing border style andproximity to neatline on page 374 )

• Position (see Setting the updating behavior on page 395)

• Quick Style (see Selecting an existing quick style onpage 397 )

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Changing border style and proximityto neatline

A border is a decorative frame around a Map. For moreinformation, see About borders on page 373 . Theposition of a border is based on the position of a neatlineor on the Area if the neatline is not set.

1. From the Maps tree, right-click a border and clickProperties.

2. In the Border Properties dialog box, click theGeneral tab.

3. Click the Style button and create a style for theborder (see Selecting a style on page 354 ).

4. In the Distance To Neatline area, enter a valuerepresenting the distance from the left border to theleft neatline (or Area) in the Left spin box andchoose a unit of measurement from the list box.

If you want to keep the distance between the borderand the neatline (or Area) the same on all sides,enable the Keep equal check box and go to step 8.

5. Enter a value representing the distance from theright border to the neatline (or Area) in the Rightspin box.

6. Enter a value representing the distance from the topborder to the neatline (or Area) in the Top spin box.

7. Enter a value representing the distance from thebottom border to the neatline (or Area) in theBottom spin box.

8. Click OK.

About grids

A grid is an array of regularly-spaced parallel andperpendicular lines arranged over an Area. Each cell isused as a reference point for determining locations orcoordinates. For example, they can be used inconjunction with street indexes.

A grid

A graticule is drawn along latitude and longitude lines ora representation that relates points in an Area tolocations on the ground.

A georeferenced graticule

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Georeferenced grids are linked to Area data. They can beused to locate and reference Map features with the Earththrough georeferenced coordinate systems.Georeferenced grids are not always rectilinear. Forexample, latitude/longitude grids have curved grid lines,while UTM grids have both curved and straight lines.

The position of a grid is based on the position of aneatline or on an Area if a neatline is not set.

To add a grid to an area, see Creating a surround onpage 371 . You cannot create a grid in a rotated Area(Raster Up). For more information, see About rotatedrasters on page 34 .

To open the Grid Properties dialog box, see Settingsurround element properties on page 372 .

The look of a grid (or graticule) is determined by its:

• General properties (see Changing grid pacing andproximity to neatline on page 375 )

• Layout properties (see Changing the style andlayout of the grid on page 376 )

• Headings properties (see Changing the location andstyle of the grid headings on page 377 )

• Label properties (see Changing the location andstyle of the grid labels on page 377 )

• Position (see Setting the updating behavior on page 395)

• Quick Style (see Selecting an existing quick style onpage 397 )

Changing grid pacing and proximity

to neatline

The position of a grid is based on the position of theneatline or on an Area if the neatline is not set.

1. From the Maps tree, right-click a grid and clickProperties.

2. In the Grid Properties dialog box, click the Generaltab.

3. In the Distance To Neatline area, enter a valuerepresenting the distance from the left border to theleft neatline (or Area) in the Left spin box andchoose a unit of measurement from the list box.

If you want to keep the distance between the borderand the neatline (or Area) the same on all sides,enable the Keep equal check box and go to step 7.

4. Enter a value representing the distance from theright border to the neatline (or Area) in the Rightspin box.

5. Enter a value representing the distance from the topborder to the neatline (or Area) in the Top spin box.

6. Enter a value representing the distance from thebottom border to the neatline (or Area) in theBottom spin box.

7. Enable one of the following options:

Fixed Interval: sets the grid spacing according to afixed distance between the lines. Follow step 8 tostep 10.

Fixed count: sets grid line spacing according to afixed number of lines. Follow step 11 and step 12.

8. In the Fixed Interval area, enable one of the

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following options:• Paper: bases a grid on paper measurements• Georeferenced: bases a grid on an Area

projection• Latitude/Longitude: bases a grid on latitude

and longitude coordinates9. Enter a value representing the horizontal width of

the column in the Column Width spin box andchoose a unit of measurement from the list box.

10. Enter a value representing the vertical width of therow in the Row Height spin box.

If you want to keep the column width and row heightthe same size, enable the Keep equal check box.

11. In the Fixed Interval area, enter a valuerepresenting the number of columns that you wantto cover the Area in the Column spin box.

12. Enter a value representing the number of rows thatyou want to cover the Area in the Row spin box.

If you want to keep the number of columns androws the same, enable the Keep equal check box.

13. Click OK.

See also

Changing the style and layout of the grid on page 376

Changing the location and style of the grid headings onpage 377

Changing the location and style of the grid labels on page 377

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Changing the style and layout of thegrid

You can change the look of a grid.

1. In the Grid Properties dialog box, click the Layouttab.

2. In the Border area, enable the Show border checkbox and click the Style button.

3. Create a style for the line (see Selecting a style onpage 354 ).

4. In the Display area, enable one of the followingoptions:

• Lines: forms the grid using solid lines• Crosses: displays only parts of the grid where

the lines intersect. Enter a value representingthe measurement for the crosses in the Sizespin box and choose a unit of measurement.

• None: hides the grid lines5. Click the Style button and create a style for the

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lines or crosses (see Selecting a style on page 354).

6. Click OK.

See also

Changing grid pacing and proximity to neatline on page375

Changing the location and style of the grid headings onpage 377

Changing the location and style of the grid labels on page 377

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Changing the location and style of thegrid headings

Headings are numbers or letters (or both) positioned onthe edges of the grid that identify the lines or sections onthe grid.

1. In the Grid Properties dialog box, click theHeadings tab.

2. In the Location and Appearance area, enable anyof the check boxes to indicate where you want theheadings to appear.

3. Click the Style button and create a style for the text(see Selecting a style on page 354 ).

4. Enter a measurement representing the space that

you want between the grid border and the headingsin the Distance from grid spin box.

5. In the Type area, enable one of the followingoptions:

• Geo style: aligns the headings with the gridlines.Choose a format representing how youwant the headings to appear in the Format listbox.

• Paper style: center the headings between thegrid lines. Choose an alphabetic or numericformat from the Rows and Columns listboxes.

By default, headings are ordered from the top downand from left to right. If you want to reverse theorder, enable the Reverse check box for the row orcolumn, or both.

6. Click OK.

See also

Changing grid pacing and proximity to neatline on page375

Changing the style and layout of the grid on page 376

Changing the location and style of the grid labels on page 377

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Changing the location and style of the

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grid labels

Labels are the numbers positioned on the grid lines thatshow the Northings and Eastings for a grid. You canchange the look of the numbers and adjust the position ofNorthings and Eastings relative to the grid lines.

1. In the Grid Properties dialog box, click the Labeltab.

2. In the Easting Placement area, enable any of thecheck boxes to indicate where you want the label tobe positioned in reference to the lines on the X-axis.UR represents upper right, UL represents upper left,LR represents lower right, and LL represents lowerleft.

3. Enter a value representing the space between thelabel and the Y-axis as the label moves along theX-axis in the Horizontal Offset spin box.

If you want to have both the horizontal offset andvertical offset the same distance from the lines,enable the Keep equal check box and skip step 4.

4. Enter a value representing the space between thelabel and the X-axis as the label moves along theY-axis in the Vertical Offset spin box.

5. In the Northing Placement area, enable any of thecheck boxes to indicate where you want the label tobe positioned in reference to the lines on the Y-axis.UR represents upper right, UL represents upper left,LR represents lower right, and LL represents lowerleft.

6. Enter a value representing the space between thelabel and the Y-axis as the label moves along theX-axis in the Horizontal Offset spin box.

If you want to have both the horizontal offset andvertical offset the same distance from the lines,enable the Keep equal check box and skip step 7.

7. Enter a value representing the space between thelabel and the X-axis as the label moves along theY-axis in the Vertical Offset spin box.

8. In the Appearance area, click the Style button andcreate a left-aligned style for the text (see Selectinga style on page 354 ).

9. Choose a format that represents how you want thelabels to appear from the Format list box.

10. Click OK.

See also

Changing grid pacing and proximity to neatline on page

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375

Changing the style and layout of the grid on page 376

Changing the location and style of the grid headings onpage 377

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

About legendsA legend is a list of colors, symbols, and patternsdisplayed in an Area with a description or label explainingwhat each means. Each color, symbol, and pattern isrepresented in the legend by a small sample or exampleof itself. The legend is anchored to the neatline or to anArea if a neatline is not set and is positioned in referenceto that anchor.

Example of a legend

To add a legend to an Area, see Creating a surround onpage 371 . To open the Legend Properties dialog box,see Setting surround element properties on page 372 .

The look of a legend is determined by its:

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• General properties (see Setting the number ofcolumns and designing a border for a legend onpage 380 )

• Title properties (see Adding a title to the legend onpage 380 )

• Filter properties (see Adding styles to a legend onpage 381 )

• Structure properties (see Organizing sections in alegend on page 382 andCreating a design forsections in a legend on page 383 )

• Columns properties (see Organizing legendcolumns on page 384 )

• Position (see Setting the updating behavior on page 395)

• Quick Style (see Selecting an existing quick style onpage 397 )

Setting the number of columns anddesigning a border for a legend

The General properties of a legend control the number ofcolumns into which it is divided, the alignment of thecolumns, and the style of the borders.

1. From the Maps tree, right-click a legend and clickProperties.

2. In the Legend Properties dialog box, the Generaltab.

3. In the Columns area, enter a value for the numberof columns that you want in the Number ofcolumns box.

4. Enable one of the following Column alignmentoptions:

• Top: aligns the columns along their top edges

• Bottom: aligns the columns along their bottomedges

5. In the Borders area, enable any of the followingcheck boxes:

• Show legend border: creates a borderaround the legend. Click the Style button andcreate a style (See Selecting a style on page354 ).

• Show sample border: draws an outlinearound each sample in the legend. Click theStyle button and create a style (see Selectinga style on page 354 ).

6. Click OK.

See also

Adding a title to the legend on page 380

Adding styles to a legend on page 381

Organizing sections in a legend on page 382

Creating a design for sections in a legend on page 383

Organizing legend columns on page 384

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Adding a title to the legend

A title is the main heading for a legend. It identifies the

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information included in the legend. Subtitles inside alegend are controlled on the Structure tab (SeeOrganizing sections in a legend on page 382 ).

1. In the Legend Properties dialog box, click the Titletab.

2. Enable the Show title check box.3. Type the legend title in the Title box.4. Click the Style button and create a style (see

Selecting a style on page 354 ).5. Enable one of the following Title placement

options:• Top: places the title at the top of the legend• Bottom: places the title at the bottom of the

legend6. Enter a value representing the distance between the

title and the legend in the Spacing from columnsspin box and choose a unit of measurement fromthe list box.

7. Enable one of the following Alignment options:• Left: aligns the title along the left edge of the

legend• Center: centers the title over or under the

legend• Right: aligns the title along the right edge of

the legend8. Click OK.

See also

Setting the number of columns and designing a border fora legend on page 380

Adding styles to a legend on page 381

Organizing sections in a legend on page 382

Creating a design for sections in a legend on page 383

Organizing legend columns on page 384

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Adding styles to a legend

You can make a first draft of the legend in a filter table.The table contains all layers in an Area. You can selectlayer styles or whether you want the legend to contain allthe styles in the Representation Style Table (RST) linkedto the selected layers or only the styles that are used inthe Area. Once you have made an initial selection, youcan refine the legend.

Cells that appear gray under the All Repcode column inthe filter table indicate the layer is not associated to anindirect RST and cannot be used in the legend. For moreinformation about RSTs, see Understandingrepresentation on page 352 .

If a style in the RST contains a text attribute, you caninclude it in the legend. The style associated to a textattribute is represented in the legend by a capital letter Tin the corresponding style. For more information abouttext attributes, see Using an attribute as part of the styleon page 355 .

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1. In the Legend Properties dialog box, click theFilter tab.

2. Click a layer in the Generate column.

A check mark indicates a layer is included in thelegend.

3. Click a layer in the All Repcode column that youwant in the legend.

A check mark indicates a layer is included in thelegend.

If you want to include styles associated to the textattributes in the legend, enable the Add text to RSThierarchy check box.

4. Click OK.

See also

Setting the number of columns and designing a border fora legend on page 380

Adding a title to the legend on page 380

Organizing sections in a legend on page 382

Creating a design for sections in a legend on page 383

Organizing legend columns on page 384

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Organizing sections in a legend

You can refine a legend and design its look. The RSThierarchy list contains all RSTs associated with layers,even those not uses in the Area. Items listed in theLegend hierarchy box appear in the legend.

You can group items under sections and subsections tomake the information more easily found in an Area. In thefollowing figure, the items are separated in two sections:Transportation and Sports Facilities. The Sports Facilitiessection is divided into two subsections, making it easierto find the Indoor Pool.

Example of the organization of a legend

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To add sections

1. In the Legend Properties dialog box, click theStructure tab.

2. In the Legend hierarchy list, select the sectionunder which you want to add a subsection.

3. Click the Add button.

To remove sections

1. In the Legend Properties dialog box, click theStructure tab.

2. In the Legend hierarchy list, select a section.3. Click the Remove button.

To move an item to a section

• Drag an item to a section.

To add an item from an RST to a legend

1. In the Legend hierarchy list, select a section.2. In the RST hierarchy box, select an item.3. Click the button between the lists. For more

information, see:• Setting the number of columns and designing

a border for a legend on page 380• Adding a title to the legend on page 380• Adding styles to a legend on page 381• Creating a design for sections in a legend on

page 383• Organizing legend columns on page 384

• Setting the updating behavior on page 395• Selecting an existing quick style on page 397

Creating a design for sections in alegend

Once you have decided the groupings that you want inthe legend (see Organizing sections in a legend on page382 ), you can define the font for the titles and the designfor the delimiters.

1. In the Legend Properties dialog box, click theStructure tab.

2. Select a section title in the Legend hierarchy box.

The default section titles are Base Section, NewGroup, and Default Section.

3. Enable the Show section title check box.4. Click the Title style button and create a title style

(see Selecting a style on page 354 ).5. Click the Item text style button and create an item

text style (see Selecting a style on page 354 ).6. Click the Delimiter style button and create a

delimiter style (see Selecting a style on page 354 ).7. Enable one of the following Sample placement

options to determine which side the samples appearin the legend:

• Left: places the samples on the left followedby their descriptions

• Right: places the descriptions followed bysamples on the right

8. Click Advanced and determine the position ofdescriptions, the size of samples, the position ofsection titles, and the length of delimiters. For more

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information, see Customizing a section layout onpage 384 .

If you want to change the selected section orsubsection title, click it and type a new title.

9. Click OK.

See also

Setting the number of columns and designing a border fora legend on page 380

Adding a title to the legend on page 380

Adding styles to a legend on page 381

Organizing sections in a legend on page 382

Organizing legend columns on page 384

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Customizing a section layout

Using the legend advanced properties, you cancustomize the alignment and spacing of the legend titles,subtitles, and delimiters, and determine the size of thecolor, symbol, and pattern samples.

1. In the Legend Properties dialog box, click theStructure tab and click Advanced.

2. Enable one of the following Description alignment

options:• Left: aligns the description or label for the

sample to the left• Right: aligns the description or label to the

right3. Enter a value that represents the indent between

the left border and the left side of the legend in theLeft spin box and choose a unit of measurementfrom the list box.

4. Enter a value that represents the indent betweenthe right border and the right side of the legend inthe Right spin box.

If you want to have both the left and right sides thesame distance from the border, enable the Keepequal check box.

5. Enter a value that represents the space betweeneach item in the list in the Inter-item spacing spinbox.

6. In the Sample size area, enter a value representingthe width and height of the box in the Width andHeight spin boxes.

7. In the Section title area, enable an Alignmentoption.

8. Enter a value that represents the spacing aboveand below the title in the Above and Below spinboxes.

9. Enable the Delimiters check box.10. Enter a value for the Minimum length, Lead, and

Tail spin boxes for the delimiters.11. Click OK.

Organizing legend columns

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You can specify the list item that appears at the top ofeach column, customize the width and margins of theindividual columns, and define a style for a border.

1. In the Legend Properties dialog box, click theColumns tab.

2. Choose the number for the column you want to editin the Edit column list box.

3. Choose the legend item that you want listed as thefirst item in the selected column in the Select startitem for this column list box.

If you want to reinstate the default, click Reset startitems.

4. Enter a value that represents the width of theselected column in the Width spin box and choosea unit of measurement from the list box.

5. If you want all columns to be of equal width, enablethe Keep all columns same width check box.

6. Enter a value that represents the distance betweenthe left border and the left side of the legend itemsin the Left spin box.

7. Enter a value that represents the distance betweenthe right border and the right side of the legenditems in the Right spin box.

If you want to keep the margin sizes equal, enablethe Keep equal check box.

8. Enable the Show column border check box.9. Click the Style button and create a style (see

Selecting a style on page 354 ).10. Click OK.

See also

Setting the number of columns and designing a border fora legend on page 380

Adding a title to the legend on page 380

Adding styles to a legend on page 381

Organizing sections in a legend on page 382

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Adding a picture to a map

You can add a picture, such as an image, a graphic, or alogo to a Map. The picture is anchored to the neatline orto the Area if a neatline is not set and is positioned inreference to that anchor.

To add a picture to an Area, see Creating a surround onpage 371 . To open the Picture Properties panel, seeSetting surround element properties on page 372 .

1. From the Maps tree, right-click a picture elementand click Properties.

2. Click the General tab and click Browse.3. In the File Selector dialog box, locate and select a

file, and click Open.4. In the Picture Properties dialog box, enter a value

that represents the horizontal size of the picture inthe Width spin box and select a unit ofmeasurement from the list box.

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5. Enter a value that represents the vertical size of thepicture in the Height spin box.

6. Click OK.

See also

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

About north arrowsNorth arrows are graphical representations indicatingwhere north is in the Area. By default, north arrows areplaced vertically in the Area, which usually points north,except in a rotated Area (Raster Up). When you create anorth arrow in a rotated Area, the north arrow is rotatedby the amount set in the Area properties. For moreinformation, see About Rotated Rasters on page 34 .North arrows are anchored to a neatline or to an Area if aneatline is not set, and are positioned in reference to thatanchor.

Focus offers three arrow types:

• True North: the arrow points to geographic northpole where the lines of longitude converge.

• Magnetic North: the arrow points to the magneticnorth pole, which is the direction indicated by amagnetic compass.

• Grid North: the arrow points in a northerly directionalong a grid line parallel to the central meridian ofthe Area projection. This arrow is most often used intopographic maps.

You can add more than one north arrow to an Area andset each arrow property separately. Several defaultsymbols are available; you can also use the SymbolEditor (see Designing a symbol on page 360 ) to designyour own.

To add a north arrow to an Area, see Creating a surroundon page 371 . To open the North Arrow Properties dialogbox, see Setting surround element properties on page372 .

To define a North Arrow, see:

• True North (see Setting the angle and style for atrue North arrow on page 386 )

• Magnetic North (see Setting the angle and style forthe magnetic north arrow on page 387 )

• Grid North (see Setting the angle and style for thegrid north arrow on page 388 )

• Position (see Setting the updating behavior on page 395)

• Quick Style (see Selecting an existing quick style onpage 397 )

Setting the angle and style for a trueNorth arrow

A True North arrow is a symbol that indicates thedirection of the geographic north pole in an Area. Formore information, see About north arrows on page 386 .

1. From the Maps tree, right-click an arrow elementand click Properties.

2. In the North Arrow Properties dialog box, click the

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True North tab and enable the Show true northarrow check box.

3. Enter a value that represents the counterclockwiserotation that you want to apply so that the arrowpoints north in the Angle spin box and choose aunit of angular measurement from the list box.

4. Click the Style button and create an arrow style(see Selecting a style on page 354 ).

5. Enable the Show arrow label check box andchoose a label from the list box.

If you want to customize the position of the label,click Advanced.

6. Click the Style button and create a font style (seeSelecting a style on page 354 ).

7. Click OK.

See also

Setting the angle and style for the magnetic north arrowon page 387

Setting the angle and style for the grid north arrow onpage 388

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Adjusting the position of a northarrow label

1. In the North Arrow Properties dialog box, click theTrue North tab and click Advanced.

2. In the North arrow heading - Advanced dialogbox, enter a value that represents the spacebetween the arrow and the label in the Distancefrom arrow spin box and choose a unit ofmeasurement from the list box.

3. Enable one of the following Angle options:• Custom: adjusts the angle of the label. Enter

a value that represents the rotation that youwant in the spin box and choose a unit ofmeasurement from the list box.

• Perpendicular: changes the angle of the labelso it is vertical to the baseline of the map

• Parallel: changes the angle of the label so itcoincides with the baseline of the map

4. Enable one of the following Alignment options:• Left: places the label to the left of the arrow• Center: centers the label over the arrow• Right: places the label to the right of the arrow

5. Click OK.

Setting the angle and style for themagnetic north arrow

1. In the North Arrow Properties dialog box, click theMagnetic North tab and enable the Showmagnetic north arrow check box.

2. Enter a value that represents the counterclockwiserotation that you want to apply so that the arrowpoints north in the Angle box and choose a unit ofangular measurement from the list box.

3. Click the Style button and create an arrow style

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(see Selecting a style on page 354 ).4. Enable the Show arrow label check box and

choose a label from the list box.

If you want to customize the position of the label,click Advanced.

5. Click the Style button and create a font style (seeSelecting a style on page 354 ).

6. Click OK.

See also

Setting the angle and style for a true North arrow on page386

Setting the angle and style for the grid north arrow onpage 388

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Setting the angle and style for the gridnorth arrow

1. In the North Arrow Properties dialog box, click theGrid North tab and enable the Show grid northarrow check box.

2. Enter a value that represents the counterclockwiserotation that you want to apply so that the arrowpoints north in the Angle box and choose a unit ofangular measurement from the list box.

3. Click the Style button and create an arrow style(see Selecting a style on page 354 ).

4. Enable the Show arrow label check box andchoose a label from the list box.

If you want to customize the position of the label,click Advanced.

5. Click the Style button and create a font style (seeSelecting a style on page 354 ).

6. Click OK.

See also

Setting the angle and style for a true North arrow on page386

Setting the angle and style for the magnetic north arrowon page 387

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

About scale barsA scale bar is a visual aid to help you measure actualground distances in an Area. It is marked withmeasurement units in proportion to the scale of the Area.Scale bars are anchored to a neatline or to an Area if aneatline is not set and are positioned in reference to thatanchor.

You can create two types of scale bars:

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• Line and Tick

• Bar

If you want to show two different scales, such askilometers and miles, you must create two separate scalebars. If you want both scale bars lined up at zero, youmust align them manually.

To add a scale bar to an Area, see Creating a surroundon page 371 . To open the Scale Bar Properties panel,see Setting surround element properties on page 372 .

The look of a scale bar is determined by its:

• General properties (see Determining the style andposition of the title for the scale bar on page 389 )

• Scale bar type (see Selecting a scale bar type onpage 390 )

• Division (see Setting the divisions for the scale baron page 390 )

• Subdivision (see Setting subdivisions for a scale baron page 392 )

• Style (see Designing a Line and Tick scale bar onpage 393 )

• Position (see Setting the updating behavior on page 395)

• Quick Style (see Selecting an existing quick style onpage 397 )

Determining the style and position ofthe title for the scale bar

1. From the Maps tree, right-click a scale bar and clickProperties.

2. In the Scale bar Properties dialog box, click theGeneral tab and enable the Show title check box.

3. Type a title for the scale bar in the Show title box.

By default, the title is the current scale in the Area.

4. Click the Style button and create a font style of thescale bar title (see Selecting a style on page 354 ).

5. Enable one of the following options for the titleplacement:

• Above: displays the title on top of the scalebar

• Below: displays the title under the scale bar6. Enable a title Alignment option.7. Enter a value that represents the space between

the title and the scale bar in the Distance fromscale bar box, and choose a unit of measurementfrom the list box.

8. Click OK.

See also

Selecting a scale bar type on page 390

Setting the divisions for the scale bar on page 390

Setting subdivisions for a scale bar on page 392

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Designing a Line and Tick scale bar on page 393

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Selecting a scale bar type

1. From the Scale bar Properties dialog box, click theScale bar type tab.

2. Enable one of the following options:• Line and Tick : uses a Line and Tick scale

bar.• Single bar: uses a scale bar type with one row• Double bar: uses a scale bar type with two

rows• Triple bar: use a scale bar type with three

rows3. Click OK.

See also

Determining the style and position of the title for the scalebar on page 389

Setting the divisions for the scale bar on page 390

Setting subdivisions for a scale bar on page 392

Designing a Line and Tick scale bar on page 393

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Setting the divisions for the scale bar

A scale bar is separated into sections called divisions.Divisions represent the actual ground distances asdisplayed in an Area. To provide a greater degree ofaccuracy, you can provide smaller increments bysubdividing a division, as shown in the following example.Divisions and subdivisions can display headings thatindicate the distance in the selected measurement unit.

1. From the Scale bar Properties dialog box, click theDivision tab and enable the Automatic divisionscheck box.

If you want to manually set the number of divisions,disable the Automatic divisions check box, enterthe number of divisions that you want in theNumber of divisions spin box, enter a value thatrepresents the real distances on the ground that thedivision covers in the Division size spin box, and

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choose a unit of measurement.

If you want to display a unit of measurement on thescale bar and set which tick represents zero, clickAdvanced.

2. Enable the Show headings check box.3. Click the Style button and create a heading font

style (see Selecting a style on page 354 ).4. Enable one of the following Placement options:

• Top: places the headings on top of thedivisions

• Bottom: places the headings under thedivisions

• For the Line and Tick scale bar type, ticks areplaced on the same side as the headings.

5. Enter a value that represents the space betweenthe headings and scale bar in the Distance fromscale bar spin box and choose a unit ofmeasurement from the list box.

6. Click OK.

See also

Determining the style and position of the title for the scalebar on page 389

Selecting a scale bar type on page 390

Setting subdivisions for a scale bar on page 392

Designing a Line and Tick scale bar on page 393

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Labeling a scale bar with a unit ofmeasurement and setting a zero tick

You can specify where a unit of measurement isdisplayed on a scale bar and which tick represents zero.

1. From the Scale bar Properties dialog box, click theDivision tab, disable the Automatic divisionscheck box, and click Advanced.

2. In the Scalebar Divisions - Advanced dialog box,enable any of the following check boxes:

• Place units label at the start of scale bar:displays a unit of measurement to the left ofthe scale bar. Choose a unit of measurementfrom the Label list box.

• Place units label at the end of scale bar:displays a unit of measurement to the right ofthe scale bar. Choose a unit of measurementfrom the Label list box.

3. Click the Style button and create a label font style(see Selecting a style on page 354 ).

4. Enter a number of the tick on your scale bar where

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you want the zero mark to appear in the Zero is attick spin box.

5. Click OK.

Setting subdivisions for a scale bar

To provide a greater degree of accuracy, you can providesmaller increments by subdividing a division.

1. From the Scale bar Properties dialog box, click theSubdivisions tab and enable the Showsubdivisions check box.

2. Enter the number of subdivisions you want in thescale bar in the Number of subdivisions spin box.

If you want to specify how many and which divisionsto subdivide, click Advanced.

3. Enable the Show headings check box.4. Click the Style button and create a font heading

style (see Selecting a style on page 354 ).5. Enable a heading Placement option.6. Enter a value that represents the space between

the headings and scale bar in the Distance fromscale bar spin box and choose a unit ofmeasurement from the list box.

7. Click OK.

See also

Determining the style and position of the title for the scalebar on page 389

Selecting a scale bar type on page 390

Setting the divisions for the scale bar on page 390

Designing a Line and Tick scale bar on page 393

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Specifying which divisions tosubdivide

You can choose the number of subdivisions you want in ascale bar and where to show the subdivisions.

For example, one subdivision in the scale bar can bedisplayed in the second division, as shown in thefollowing illustration.

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1. From the Scale bar Properties dialog box, click theSubdivision tab and click Advanced.

2. In Scalebar Subdivisions Advanced dialog box,enter the number of divisions you want to subdividein the Divisions to subdivide spin box.

3. Enter the number of the division where you want tobegin showing the subdivisions in the Starting atdivision spin box.

4. Click OK.

Designing a Line and Tick scale bar

For a Line and Tick scale bar, you can determine thecolor, thickness, and height of the ticks. For a Single,Double, or Triple scale bar, you can determine the colorand pattern of the divisions and subdivisions, and theheight and the outline.

For example, in a Line and Tick scale bar, the ticks canoverlap the scale bar as shown:

You can also choose the colors for a scale bar pattern:

1. In the Scale bar Properties dialog box, click theScale Bar Type tab and enable the Tick and Lineoption.

2. Click the Style tab.3. In the Scalebar area, click the Style button and

create a style for the bar (see Selecting a style onpage 354 ).

If you want the ticks to overlap the scale bar, enablethe Center ticks vertically on scale bar check box.

4. In the Division Ticks area, click the Style buttonand create a division ticks style (see Selecting astyle on page 354 ).

5. Enter a value that represents the length of a divisiontick in the Tick height spin box.

6. In the Subdivision Ticks area, click the Stylebutton and create a subdivision ticks style (seeSelecting a style on page 354 ).

7. Enter a value that represents the length of thesubdivision tick in the Tick height spin box.

8. Click OK.

Designing a single, double, or triple

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scale bar1. In the Scale bar Properties dialog box, click the

Scale Bar Type tab, enable the Single bar, Doublebar, or Triple bar option, and click the Style tab.

2. In the Colors area, click any section box andchoose a color from the color palette.

3. Enter a value that represents the total height of allsections in the scale bar in the Scale bar heightspin box and choose a unit of measurement fromthe list box.

For a triple-bar style, you can set the height of themiddle row differently than the top and bottom rowsby entering a value representing the height of themiddle row of the scale bar in the Middle sectionheight spin box.

4. Enable the Show outline check box and click theStyle button to create an outline style (seeSelecting a style on page 354 ).

5. Click OK.

See also

Determining the style and position of the title for the scalebar on page 389

Selecting a scale bar type on page 390

Setting the divisions for the scale bar on page 390

Setting subdivisions for a scale bar on page 392

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Adding a map title to an area

You can add a title and subtitle to an Area, adjust theirpositions, and change their font styles. The title andsubtitle are anchored to a neatline or to the Area if aneatline is not set and positioned in reference to thatanchor.

To add a title and subtitle to an Area, see Creating asurround on page 371 . To open the Title Propertiespanel, see Setting surround element properties on page372 .

1. From the Maps tree, right-click a title element andclick Properties.

2. Click the General tab and type a title for the Area inthe Title box.

3. Click the Style button and create a font style (seeSelecting a style on page 354 ).

4. Enable the Subtitle check box and type a subtitle inthe box.

If you want to change the font of the subtitle, clickthe Style button and create a style (see Selecting astyle on page 354 ).

5. Enter a value that represents the space betweenthe title and subtitle in the Spacing from title spinbox and choose a unit of measurement from the listbox.

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6. Enable one of the following Alignment options:• Left: aligns the title and subtitle to the left• Center: centers the title and subtitle• Right: aligns the title and subtitle to the right

7. Click OK.

See also

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Adding text to a surround

You can include a paragraph of text with the other Mapsurround elements. You can set a text style, import textfrom another file, set the position of a paragraph, andchange the Quick Style format of the paragraph text. Aparagraph element is anchored to a neatline or to theArea if a neatline is not set and positioned in reference tothat anchor. Multiple styles are not allowed in individualtext elements.

You can also rotate a paragraph. Text remainsperpendicular to the baseline of the element.

To add a text to an Area, see Creating a surround onpage 371 . To open the Paragraph Properties panel, seeSetting surround element properties on page 372 .

1. From the Maps tree, right-click a paragraph elementand click Properties.

2. Click the General tab and type in the Text box.

If you want to change the font of the text, click theStyle button and create a style (see Selecting astyle on page 354 ).

3. Enter a value that represents the angle of rotationyou want to apply to the text in the Angle spin boxand choose a unit of angular measurement from thelist box.

If you want to import text from a text file, clickImport Text, locate and select a file in the FileSelector dialog box, and click Save.

4. Click OK.

See also

Setting the updating behavior on page 395

Selecting an existing quick style on page 397

Setting the updating behavior

Depending on the type of surround element, thepositioning method differs:

For Neatline: The position of a neatline is calculatedrelative to the extents of the Area.

For Border and Grid: The position of a border and gridis calculated relative to the extents of a neatline. If noneatline is used, the positions are calculated relative tothe extents of the Area.

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For Legend, Picture, North Arrow, Scale bar, Title,and Paragraph: Elements are anchored to a neatlineand are positioned in reference to that anchor. If noneatline is used, the surround element positions arecalculated relative to the extents of the Area. The locationof a surround element is determined by the Offset, whichis the horizontal (X) and vertical (Y) coordinatesmeasured from the anchor. You can see the neatline orthe Area represented by a rectangle with white handles.The surround element is represented by a rectangle withgray handles. You can anchor any one of the surroundelement handles to any one of the neatline or Areahandles. To change the location of a surround element,you can drag the surround element by its handle, or youcan enter new values.

If you want to modify the neatline or Area after you haveset the properties for the surround elements, you can sethow they behave:

• Reposition: the surround element automaticallyadjust its position in correlation with a neatline (orArea), but retains its original settings.

• Regenerate: the surround element is recalculatedand positioned based on new settings for a neatline(or Area). This behavior is useful for the neatline,border, grid, and scale bar elements.

• Do nothing: the surround element does not adjustto the new settings and remains as originallypositioned.

1. From the Maps tree, right-click a surround elementand click Properties.

2. In the surround element Properties dialog box, clickthe Position tab.

3. In the Updating area, choose how you want the

surround element to react when a neatline (or Area)changes position from the When neatline/areamoves list box.

4. Choose how you want the surround element toreact when the scale of a neatline (or Area)changes from the When area/neatline is rescaledlist box.

5. In the When area/neatline is resized list box,choose how you want the surround element to reactwhen a neatline (or Area) is enlarged or reduced insize.

6. Click Apply.

Setting the offset (not available forneatline, border, and grid)

1. In the Offset area, enter a value for the horizontalposition in the X spin box and a value for the verticalposition in the Y spin box.

You can also click a gray handle and drag thesurround element into position.

2. In the preview area, click a gray handle.3. Click a white handle to determine the anchor point.

By default, the origin of a starting point of a grid is thelower-left corner of a neatline.

Setting a grid starting point1. Enable the Use starting point check box.2. Enter an X-coordinate for the new starting point in

the X spin box.3. Enter a Y-coordinate for the new starting point in the

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Y spin box.

Understanding Grids

Selecting an existing quick style1. From the Maps tree, right-click a surround element

and click Properties.2. In the surround element Properties dialog box, click

the Quick Style tab.3. Select a Quick Style.4. Click OK.

Removing a custom quick style fromthe list

1. From the Maps tree, right-click a surround elementand click Properties.

2. In the surround element Properties dialog box, clickthe Quick Style tab.

3. Select a custom Quick Style and click the RemoveQS button.

Creating a custom quick style

As you set the properties for surround items, you build aCurrent Working Style. You can save the settings for asurround element in a Quick Style.

When you select a Quick Style, the settings are copied tothe Current Working Style and are applied to thesurround item. If you change the properties, the changesare applied to the Current Working Style, not to the QuickStyle.

1. From the Maps tree, right-click a surround elementand click Properties.

2. In the surround element Properties dialog box,make changes to the properties of the surroundelement.

3. Click the Quick Style tab and click the Add QSbutton.

If you want to rename the new Quick Style,double-click it, type a name, and press Enter.

Creating an index for a project, youmust provide

Indexing a Map means you extract information, sort it astext information, and present it as part of a surround. Forexample, you can create an index of streets, cities,

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buildings, or parks, or a combination of these.

An index lists the Map locations and features. The namesof the items are usually listed in alphabetical order. Youcan use combinations of letters and numbers thatcorrespond to grid locations on the Map.

1. Index Information: All content used in the indexmatching specified conditions. You can compose alist of these items.

2. Information: A reference that identifies a locationfor each item in the index, information matchesspecified conditions. You can specify gridinformation.

Adding a default index to a map1. On the toolbar, click Map View Mode.

Note: The image must be in Map View Mode for theIndexation dialog box to be accessible.

2. From the Maps tree, right-click an Area and clickIndexation.

3. In the Indexation dialog box, click OK.

Indexation propertiesYou can set the properties for an index, including filtersand lists.

Filtering:

Specifies the type of information you want to include in anindex. For example, you may want to include only road

and building names. You can also edit redundant words,such as #street# from appearing in the index.

Index List:

Generates an alphabetical listing of index entries withgrid locations. You can add, delete, and modify listentries. Verification Mode, when enabled, is used tointeractively locate a list entry within the current Map.

An index is generated in its own area on a Map, which isdesignated as Indexation. There is only one layer in anindex area.

A grid created by the index is also generated in its ownarea on the Map and is designated as Index. There isonly one layer in a grid area.

Setting general parameters for anindex

You can set the number of columns, column spacing, andRepCode for an index.

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Changing headings, entries, and delimiters in theRepCodes area of the General page.

1. On the toolbar, click Map View Mode.

Note: The image must be in Map View Mode for theIndexation dialog box to be accessible.

2. From the Maps tree, right-click an Area and clickIndexation.

3. In the Indexation dialog box, click the General tab.4. Enter a value that represents the number of index

columns in the Number of columns spin box.5. Enter a value that represents the width of the index

columns in the Column width spin box.6. Enter a value that represents the spacing between

columns in the Inter-column spin box and choose aunit of measurement from the list box.

7. Enter a value that represents the spacing betweenitems in the index in the Inter item spin box.

8. In the Repcode area, enter a code in any of thefollowing boxes:

• Index Item• Headings• Delimiter• Index Border

You can also click Browse for the correspondingbox and select a RepCode.

If you want to include a border, enable the Showindex border check box.

9. Click OK.

Change these parts of an index with the Indexationproperties dialog box

Adding or change the index title

1. From the Indexation dialog box, click the Title tab.2. Enable the Show index title check box and type a

title in the box.3. Type a RepCode in the Index title RepCode box.

You can also find a title code by clicking Browseand selecting a RepCodes in the BrowseRepCodes dialog box.

4. Click OK.

Opening an indexation parameter file

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1. From the Indexation dialog box, click the Title tab.2. In the Parameter File area, click Load.3. In the File Selector dialog box, locate and select a

file, and click Open.

When accessing an existing parameter file, it must beused with the same Area for which it was originallycreated. If you select another Area, the settings are resetto the default.

Setting up an index

The Indexation process requires a grid to properlyreference the location of text. The grid defines thelocation of the text that is to be extracted.

1. In the Indexation dialog box, click the Grid tab.2. In the Extents section, do one of the following:

a. Accept the default values in the X min, X max,Y min, and Y max boxes.

b. Type a value in one or more of the followingboxes:

• X min• X max• Y min• Y max

3. Click the Display Grid check box.

Setting the spacing for rows andcolumns

You can set the spacing of columns and rows; thespacings correspond to the height of the rows and to thewidth of the columns.

1. In the Indexation dialog box, click the Grid tab.2. In the Settings section, do one of the following:

a. Accept the default values in theSpacing/Rows and the Spacing/Columnsboxes.

b. Type a value in one or both of the followingboxes:

• Spacing/Rows• Spacing/Columns

The row and the column counts are automaticallydetermined by the spacing.

3. Click one of the following:• Lock Spacing to lock the spacing values.• Lock Count to lock the count values.• No Lock.

Setting the count for rows andcolumns

You can set the number of rows and columns.

1. In the Indexation dialog box, click the Grid tab.2. In the Settings section, do one of the following:

a. Accept the default values in the Count/Rowsand the Count/Column boxes.

b. Type a value in one or both of the followingboxes:

• Count/Rows• Count/Columns

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The row and the column spacings are automaticallydetermined by the count.

3. Click one of the following:• Lock Spacing to lock the spacing values.• Lock Count to lock the count values.• No Lock.

Setting headings for rows andcolumns

1. In the Indexation dialog box, click the Grid tab.2. In the Settings section, do the following:

• In the Headings/Rows cell, choose Alphabeticor Numeric.

• In the Headings/Columns cell, chooseAlphabetic or Numeric.

Setting a RepCode for a grid heading

1. In the Indexation dialog box, click the Grid tab.2. Click Browse to the right of the Headings

RepCode box, select a RepCode from the BrowseRepCodes dialog box, and click OK.

Setting a RepCode for grid lines

1. In the Indexation dialog box, click the Grid tab.2. Click Browse to the right of the Line RepCode box,

select a RepCode from the Browse RepCodesdialog box, and click OK.

Filtering an index

You can specify the type of information you want toinclude in an index. For example, you may only want roadand building names to appear in the index. You can alsoexclude redundant words from the index.

1. From the Indexation dialog box, click the Filteringtab.

2. Select any of the following from the left-hand list:• RST• Group• RepCode

3. Click the right-arrow button.

Making a word exclusion list

A word exclusion list defines words, numbers, or acombination of words and numbers that you do not wantin the index. When building an index, all lines of text on aMap are scanned. Lines matching specified words in theword exclusion list are ignored.

The word exclusion list is not case-sensitive orspace-sensitive. It does, however, pay attention to accentmarks. A word cannot be duplicated in the list.

1. From the Indexation dialog box, click the Filteringtab.

2. Enable the Word exclusion list check box.3. Click the Add button.4. Click in the text box, type a word, and press Enter.

If you want to remove a word from the exclusion list,

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click the word and click the Remove button.

5. Click OK.

Generating an index list

You can generate an alphabetical listing of index entrieswith grid locations. You can also add, delete, and modifylist entries. Verification Mode, when enabled, interactivelylocates a list entry within the current Map.

Note: If you are using a grid element in the project, onlythe text inside a grid is added to the index.

1. From the Indexation dialog box, click the IndexList tab.

2. Click Build.

The Item count box shows the number of indexentries listed. If you want to add an item to the indexlist, click Add Selection , click in the new row, typean index entry, and press Enter.

Once you have generated an index list, you can edit theinformation.

To... Do the following:

Sort an indexalphabetically Click Sort.

Delete an item from theindex list

Select a row and clickDelete Row.

Add alphabetical headingsto the index items Click Add Headings.

To... Do the following:

Delete index headings Click Delete Headings.

Rename an item in the list Click in a row, type a newname, and press Enter.

Re-generate an index list Click OK.

Verification Mode

You can verify an index list by selecting an entry. Focusdisplays the precise location on the Map where the text islocated. If a location is not within the view pane, theIndexation module shifts to where the text is located. Thelayer where text is located must be active for theVerification tool to work properly.

Using the Verification Mode option1. In the view pane, set a zoom factor that will make

the text easy to see.2. In the Indexation dialog box, click the Index List

tab.3. Enable the Verification mode check box.4. Select the row for the index entry you want to verify.

Setting advanced indexationproperties

You can set attribute and prefix list properties for anindex.

Attributes

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You can add attribute information to the entries in anindex. For example, you can define a RepCode for citieswith a population attribute, and include the populationvalues in the index, as follows:

Ottawa (300,000)..................................D4

1. In the Indexation dialog box, click the Index Listtab.

2. Click Advanced.3. In the Indexation Advanced dialog box, enable the

Show Attributes check box.4. Select an attribute from the Select attribute to use

list.5. Select one of the following formats from the

Attribute display format list:• Keep format : displays a value as 5, 12• Integer : displays this value as 5 if a value of

5, 12 is displayed in the index6. Click OK.7. Click in the Attributes column for the cell where

you want to add the attribute information and typethe attribute information in parentheses.

8. Press Enter.9. Click OK.

Prefixes List

The prefix list words are entered in an index in reverseorder. For example, if the word "Lake" appears in theSwap prefixes list, then "Lake Rice" appears in the indexas "Rice, Lake." Index entries are sorted according to themost meaningful names.

The prefixes list follows a set of rules

1. Words to be swapped must be specified in the list.The Indexation module looks for text lines beginningwith the specified words.

2. If a word is specified in the prefixes list, then theIndexation module looks for text lines in the viewpane beginning with that word. Lines containingonly the specified word cannot be swapped.

3. When two or more words are swapped, they mustbe specified in the prefixes list if you want them toappear in the index.

4. If the prefixes list contains a repeated word, theIndexation process considers only the longestprefix. For example, when "Township of" and"Township" are in the same list, only "Township of"is used. A word cannot be duplicated in the list.

5. If the prefixes list is empty, the Swap Prefixes optionhas no effect.

6. The prefixes list is not case-sensitive orspace-sensitive, but it is aware of accent marks.

Creating or editing a prefixes list

1. From the Indexation dialog box, click the IndexList tab.

2. Click Advanced.3. In the Indexation Advanced dialog box, click the

Add button, type a word, and press Enter.

If you want to delete a word from the list, select theword and click the Remove button.

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If you want to copy the word exclusion list to theprefixes list, click the Filtering tab and click Copyexclusion list.

4. Click OK.

Using the Swap Prefixes option

1. From the Indexation dialog box, click the IndexList tab.

2. Click Swap Prefixes.3. Click OK.

Saving an indexation file

You can save your index settings.

1. From the Indexation dialog box, click the Title tab.2. In the Parameter File area, click Save.3. In the File Selector dialog box, select a folder.4. Type a name in the File name box.

If you want to overwrite an existing indexation file,select it.

5. Click Save.

Adding text to an indexYou can add text to an index and set the color and font.The text exists as an overlay on top of an image or vectorlayer. The text is different than a title; a title is a surroundelement on a Map, which is associated with a single area.This area is called the application area.

Setting the text color

1. On the Focus Display toolbar, click the Set TextColor arrow and choose a color from the palette.

2. If you want to choose a custom color, click MoreColors and create a color in the Change Colordialog box.

Setting the text style

1. On the Display toolbar, click the Set Text Stylearrow and choose a style.

If you want to choose a custom style, click MoreStyles and create a style in the Style Selectordialog box.

Using the New Text tool

1. On the Editing toolbar, click the New Text button.2. In the Text Editing Tools dialog box, enter a value

that represents the text angle in the Angle spin box,and choose a unit of measurement from the list box.

3. Select a font style from the list.4. Click OK.

Printing a map

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You can print a Map. The Print Setup dialog box specifiesthe options for printing your publication.

Vector layers placed below a raster transparency in theMaps tree appear in the view pane but are not supportedfor printing. To print all layers as they appear in the viewpane, you can export the map to a file with Export Mapand print that file separately. For more information aboutexporting a map, see Opening the Export Map dialog boxon page 407 .

• From the File menu, click Print Map.

Selecting printer optionsIf you have more than one printer available, use theName list to choose a printer. If you want to use a printerdriver that is not on the list, you must add it.

The Print to File option saves the project data as a .prnfile. This is useful if you want to print a Map to a remoteprinter. For more export options when printing to a file,see Opening the Export Map dialog box on page 407 )

Note: Other printer and paper properties can be set usingthe corresponding Map Properties dialog box.

To choose how your printer handles a print document,click Properties. Use the Document Properties dialogbox to set paper size, orientation, print duplexing, andcolor appearance.

Selecting page layout options

When you print a Map, the entire publication is printed bydefault. You can also print large maps on more than onepage, and assemble the parts after they are printed.

1. From the Print Setup dialog box, click Options.2. In the Options dialog box, choose an overlap option

from the Overlap list box.

The overlap margin for each page is 6.25 mm (1/4inch).

3. Choose one of the following options from theScaling list box:

• Actual Size : automatically prints the numberof pages required for the entire publication

• Fit to Page : scales the Map to fit on a singlesheet of paper

• Print Screen : prints only what is currentlydisplayed in the view pane

4. Choose one of the following options from theWysiwyg list box:

• As Screen : prints the Map according toselected Wysiwyg options

• Full Wysiwyg : prints the Map with fullrepresentation of lines, patterns, and text

5. Choose an image quality from the Print Quality listbox.

6. Click OK.

Printing color separations

You can separate the colors in a publication for

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commercial printing. Most color separation processes arebased on the colors cyan, magenta, yellow, and black(CMYK).

You can define spot (individual) colors in the ChangeColor dialog box color palette. In color separations, oneplate or film is produced for each color. The informationfor each plate is stored in a .ps file.

• From the Print Setup dialog box, click ColorSeparation.

Even if spot colors are defined in a color palette, only thecolors actually applied to features in the RST are listed inthe color list box.

Separate Color:

Enables all other items in the dialog box.

Negative Image

Inverts the colors in an image. By default, the colorseparations process produces a normal image. Negativeprinting is useful if you want to produce films for the Map.

Mirror:

Specifies that the film emulsion faces down. Emulsion isthe coating of light-sensitive material on a piece of film.

Convert to CMYK:

Separates all spot colors of a color palette into CMYK

colors. Separating colors in only four plates avoidsproducing an unnecessary number of plates.

Reg Marks and/or Crop Marks:

Prints registration marks or crop marks on plates, or both.Registration marks serve as guides to perfectly aligndifferent color separation plates. Crop marks are usefulwhen trimming the page to the proper size. Both marksare displayed slightly outside the graphics page extent.

Space for these marks is added to the extents of themap, even if they are disabled.

Label Marks:

Prints a label containing the names of the colors used inthe separation process. This label is displayed outsidethe Crop Marks.

Color column:

All spot colors listed in the color list box are removedfrom the list, since they are all converted to CMYK colors.

Frequency:

For each color in the list box, define the Frequency of thegrid.

Process color separations are printed using grids of blackdots for each color. The frequency in lines per inchdefines how close the dots appear. The higher thefrequency, the closer the dots and the darker the color.

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Angle:

Defines the orientation of the grid screen or the dots. Foreach color in the list box, define the angle of the grid indegrees.

Overprint:

Enables the Overprint color option for each color in thelist box.

Overprinting is used when two overlapping objects ofdifferent color are printed on two different plates. Forexample, when creating color separations for amagenta-colored circle on a cyan background, the cyanplate would have a white circle knocked out where themagenta circle prints. The cyan and magenta do not mix;however, you can set the magenta to print over the cyan.This results in the circle not being knocked out of thecyan. The two colors overprint in that area, resulting in apurple circle on a cyan background.

When a color is selected to overprint, an X appears in theOverprint column of the color list box beside the color andthe color is printed on a corresponding plate. No holescorresponding to an overlapping color will be knockedout.

If you set color frequency, angle, and overprint optionsindividually, you must select all the colors you want toprocess. However, if you click on the Convert to CMYKoption, all four basic colors are automatically selected.

You can interrupt a print job at any time by clicking

Cancel.

Note: For UNIX systems, select the PostScript Level 2driver. Color separations on UNIX are available for thisdriver only. The color separations information is printed toa single PostScript (.ps) file, which can be printed bymost commercial shops.

Opening the Export Map dialog box

Maps (see Starting a new map on page 365 ) and forcharts (see Viewing data as a chart on page 337 ) can besaved as a file.

To open the Export Map dialog box

• From the File menu, click Export Map.

To lock the record and field selection in thechart

1. See Creating a chart from the layer on page 339 .2. In the Chart dialog box, click Export Chart.

To open the Export Chart dialog box

1. In the Export Map or Export Chart dialog box, typea path and file name for the file to export in the Filebox.

You can also click Browse to locate and select a

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location.

2. Choose a file format from the Save as type list box.3. In the Options area, set the parameters, depending

on the following format types:

Adobe Illustrator: see Exporting a map orchart as an AdobeIllustrator file on page 408

JPEG: see Exporting a map orchart as a JPEG on page 408

JPEG 2000: see Exporting a map orchart to a JPEG 2000 file onpage 409

PCIDSK: see Exporting a map orchart to PCIDSK on page 409

TIFF: see Exporting a map orchart to TIFF on page 409

BMP: see Exporting a map orchart to BMP on page 410

HP RTL: see Exporting a map orchart to an HP RTL file onpage 410

EMF: see Exporting a map orchart to EMF on page 411

4. Click OK.

Exporting a map or chart as an AdobeIllustrator file

The .ai file format is the native format for Adobe Illustratorand is used primarily for vectors.

Exporting a map or chart as a JPEG

The .jpg format is best used for continuous tone images,such as photographs. It uses lossy compression, whichmeans that some data is discarded to reduce the file size.Once a file is compressed with lossy compression, theoriginal data cannot be recovered.

The Quality measure is the used to control the balancebetween the quality of the image and the reduction in thefile size. The higher the Quality value, the less data isdiscarded. You must decide a balance between file sizeand image quality, which usually falls between 0 and 80.Values over 80 usually produce an increased file sizewith little visible improvement in image quality.

1. In the Export Map or Export Chart dialog box,choose JPEG (.jpg) from the Save as type list box.

2. Enter a value that represents the resolutionproduced by the display or printer in the DPI spinbox.

The closer the match between the resolution of thefile and the display or printer, the better the qualityof the results.

3. Enter a value that represents the image quality inthe Quality box.

The lower the number, the lower the quality of theimage (more data discarded) and the smaller the file

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size.

4. Click OK.

Exporting a map or chart to a JPEG2000 file

The .jp2 format reduces a file size of extremely largeimages. It uses wavelet compression that produceshighly compressed files, while retaining better imagequality.

Lossless compression reduces the file size by reducingdata redundancies. With lossless compression, theoriginal data is restored when a file is decompressed.With lossy compression, some data is discarded toreduce the file size, which means that the original datacannot be recovered when the file is decompressed.

The Quality measure is used to control the balancebetween the quality of the image and the reduction in thefile size. The higher the Quality value, the less data isdiscarded. Lossy compression with a Quality value of 100is virtually the same as choosing lossless compression.You must decide a balance between file size and imagequality, which usually falls between 0 and 20. Values over20 produce an increased file size with little visibleimprovement in image quality.

1. In the Export Map or Export Chart dialog box,choose JPEG 2000 (.jp2) from the Save as type listbox.

2. Enter a value that represents the resolutionproduced by the display or printer in the DPI spin

box.

The closer the match between the resolution of thefile and the display or printer, the better the qualityof the results.

3. Enable one of the following options:• Lossless: uses lossless compression• Lossy: uses lossy compression. Enter a value

that represents the image quality in theQuality box.

4. Click OK.

Exporting a map or chart to PCIDSK

The .pix format is the native file format for the PCIGeomatics Geomatica product line.

1. In the Export Map or Export Chart dialog box,choose PCIDSK (.pix) from the Save as type listbox.

2. Enter a value that represents the resolutionproduced by the display or printer in the DPI spinbox.

The closer the match between the resolution of thefile and the display or printer, the better the qualityof the results.

3. Click OK.

Exporting a map or chart to TIFF

A .tif is the standard image exchange format. It is aplatform-independent file format used for bitmapgraphics. It offers lossless and lossy compression

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options.

PackBits is a lossless compression method. It reduces afile size by reducing data redundancies. With losslesscompression, the original data is restored when a file isdecompressed.

JPEG is a lossy compression method. It reduces the filesize by discarding some data. Once a file is compressedusing lossy compression, the original data cannot berecovered. In any lossy compression method, you tradethe quality of the image for a reduction in the file size.More compression means a lower quality image. Youmust decide a balance between file size and imagequality.

1. In the Export Map or Export Chart dialog box,choose TIFF (*.tif) from the Save as type list box.

2. Enter a value that represents the resolutionproduced by the display or printer in the DPI spinbox.

The closer the match between the resolution of thefile and the display or printer, the better the qualityof the results.

3. Choose one of the following options from theCompression list box:

• PACKBITS : uses lossless compression• JPEG : uses lossy compression. Enter a value

that represents the image quality in theQuality box.

4. Click OK.

Exporting a map or chart to BMP

The .bmp file format is the native bitmap file format forthe Microsoft Windows operating system.

1. In the Export Map or Export Chart dialog box,choose BMP (*.bmp) from the Save as type listbox.

2. Enter a value that represents the resolutionproduced by the display or printer in the DPI spinbox.

The closer the match between the resolution of thefile and the display or printer, the better the qualityof the results.

3. Click OK.

Exporting a map or chart to an HPRTL file

The .rtl format is used with printing devices that supportRTL, such as HP DesignJet printers. Using the .rtl formatcan speed printing by saving the data in the printerprocessing language. Because a printer does not have toprocess an .rtl file, it can print the file upon receipt.

1. In the Export Map or Export Chart dialog box,choose HP RTL (.rtl) from the Save as type listbox.

2. Enter a value that represents the resolutionproduced by the display or printer in the DPI spinbox.

The closer the match between the resolution of thefile and the display or printer, the better the qualityof the results.

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3. Choose a printer type from the HP RTL Options listbox.

4. Choose a color or black-and-white option from theColor list box.

5. Choose a dithering method from the Dither list box.

Dithering is a process that places pixels of differentcolours together to create the illusion of a color thatis not available in the palette.

If you want to save paper when using roll-fedprinters, enable the Print long edge first checkbox. This option positions the file to make theoptimum use of the paper and generate the leastamount of waste.

6. Click OK.

Exporting a map or chart to EMFThe Microsoft Enhanced Metafile (.emf) is a vectorformat that can also support bitmaps. It is compatible withMicrosoft Windows operating systems and is a goodformat to use if you want to import the Map into aMicrosoft application.

Viewing overlapping layers from aWeb mapping service

When you open maps from a Web mapping service, thedata in the topmost layer in the Maps tree may obscureall other maps. To view the map layers simultaneously,you must edit the Opacity of the layers.

1. Right-click the map layer and select Representation

Editor.2. Under the Style column, click the white style.3. Click the Edit Style tab.4. In the Values column beside Opacity, enter the

value 0.5. Click OK.

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