Tutorial - ugweb.cs.ualberta.caugweb.cs.ualberta.ca/~c206/W07/resources/LectureNotes/GIMP.pdf ·...
Transcript of Tutorial - ugweb.cs.ualberta.caugweb.cs.ualberta.ca/~c206/W07/resources/LectureNotes/GIMP.pdf ·...
GIMPGNU Image Manipulation Program
Tutorial
©Meghna Singh
Why GIMP ?
� Its FREE (open source)!
� Has all the capabilities of any other photo-editor, AND MUCH MORE!
� You can write your own filter scripts/editor tools and share with the rest of the world.
�GIMP is known to work on Linux, Windows, OpenBSD, NetBSD, FreeBSD, Solaris.
Where can I find it?
�http://www.gimp.org/
�Download
� http://www.gimp.org/windows/
� http://www.gimp.org/unix/
� http://www.gimp.org/macintosh/
�Tile Cache. 2/3 of the RAM available in your system.
GIMP interface
ToolBox Image Window
Some GIMP applications
� Image manipulation.
� Edge detection.
�Motion blurring.
� Script-Fu: A scripting language designed specifically for GIMP.
� Convolution.
� Image contrast.
� Resizing images – scaling, shearing, rotating.
� Angle finder.
Image Manipulation
??
Pick ‘knotted rope’ like tool
Ctrl C + Ctrl V
Edge detection in GIMP
Edge detection with GIMP -2
Motion blur in GIMP
Result of motion blurring
Script-Fu -- Alchemy
Script-Fu –Décor--Old photo
Filters – Artistic -- Oilify
Convolution in GIMP
Image contrast
Image Contrast-2
Image Contrast-3
Resizing images
Lock aspect ratio
Aspect ratio?? = width/height of an image
Resizing images-2
Linear interpolation
Changing the zoom
Image rotation
Basic Advanced
Image rotation -2
Image rotation -3
Image rotation - 4
Image shearing
x
y Shear in the x -direction
Shear in the y -direction
Image shearing -2
Angle finder
GIMP Layers
Layers
�Can be used very easily to animate.
�Color graphics.
�Use layers for more flexibility.
Opening the layers toolbox
Add a text layer
Add a text layer
Rotate and scale text layer
Add a pattern to an image
AIM: Make the girl run on water
1. Size the two images
�Girl image 683x1024
�Water image 2592x1944
Cut a section from the water image / scale it.
2. Open the girl image and then open
the water image as a layer
Open the layers menu
3. Before we can work with the
transparency, add alpha channel to the
background
•Click on the background layer (blue highlight)
•Right click
•Click on add alpha channel
Raise background to top of layer stack
Change the opacity of the top layer
Water from the lower layer begins to show through, BUT we don’t want water to show through the object
Add mask to top layer
�Duplicate the top layer
�Now we will work with the top most layer (copy)
Add layer mask -2
•Select the background grass region of the background copy
•From top menu click Layer�Mask�Add layer mask
•Select as shown below
Mask chosen is displayed
White = opaque
Black= transparent
Activate the rest of the layers
Get rid of the selection view
Change transparency of the middle layer
Opaque
Opaque
Opacity ~50%
Noise stems from the misc. spots in the layer mask
End result