Post on 31-Aug-2019
8.1 GIS Hardware and Software
8.2 Hybrid vs. Integrated Systems
8.3 Clients and Servers
8.4 Web-based Spatial
Databases
8.5 Summary
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 624
8 Architecture of Geographic Information Systems
[SX08]
• A geographic information system is a system designed to collect, manage, analyze, display spatial data
• Specialized information system that consists of
– Spatial database,
– Spatial database system,
– Application Software
• Often end users only seespecially programmeduser interface
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 625
8 Architecture of GIS
http://www.physicalgeography.net/
• Environmental information system
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 626
8 Architecture of GIS
[SX08]
• Tourist information system
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 627
8 Architecture of GIS
[SX08]
• Urban planning information system
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 628
8 Architecture of GIS
[SX08]
• Network information system
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 629
8 Architecture of GIS
http://www.uni-potsdam.de/Geographie/
• GIS hardware mainly differs from "normal"
information systems in the input devices
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 630
8.1 GIS Hardware and Software
http://www.uni-potsdam.de/Geographie/
• Input device: digitizer
– Collection of coordinates
– Magnifying glass with crosshairs
– Electronic pen
– Electromagnetic
surface
– Digitization of maps
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 631
8.1 GIS Hardware and Software
http://www.uni-potsdam.de/Geographie/
• Input device: drum scanner
– Oldest type of scanner
– Provides accurate results
– Usually with very high
resolution
– Original on a rotating drum
– Scanning device always in the
same position to the original
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 632
8.1 GIS Hardware and Software
http://www.at-mix.de/
http://www.litho-erfurt.de
• GIS-Software
– Components (user-oriented view)
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 633
8.1 GIS Hardware and Software
http://www.uni-potsdam.de/Geographie/
• Classification of GIS software
– Expert GIS standard GIS, spatial data server, geodatabase
– Desktop-GIS data management for collection and information
– Mobile GIS information, collection, updating
– Web-GIS information, usually no collecting and updating
– Component GIS embedding GIS functionality into third party systems
– GIS-Viewer software for displaying and querying GIS data formats
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 634
8.1 GIS Hardware and Software
http://www.esri.com/
• Architecture of GIS can be roughly classified
– File based
– Hybrid
– Layer-oriented
– Integrated
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 635
8.2 Hybrid vs. Integrated Systems
• File based architecture
– First generation of GIS (since approx. 1960)
– All information stored in files
– No logical data independence
– No physical data independence
– No standardization
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 636
8.2 Hybrid vs. Integrated Systems
• Hybrid architecture
– Relational databases are used for thematic attributes
– Spatial data is storedin specific data structureson files
– Consistency of the data is difficult toensure
– Queries whichcombine thematic and spatial attributes arenot possible
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 637
8.2 Hybrid vs. Integrated Systems
• For example, a query which is not possible with
hybrid architecture (see section 4.5)
• Attention: sometimes the term "hybrid GIS"
also is used for such systems, able to integrate
vector and raster data
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 638
8.2 Hybrid vs. Integrated Systems
SELECT b1.idFROM Building bWHERE b
SELECT b1.idFROM Building b1, Building b2WHERE b1.typeOfUse = ’church’
ANDb2.typeOfUse = ’car park’ANDDistance(Centroid(b1.groundPlan),
Centroid(b2.groundPlan)) < 2000;
• Layer-oriented architecture
– Thematic attributes and spatial data
are stored in one single (relational)
database
– Spatial data are modeled as relations
– Introduction of a layer with
geometric functions
– Inefficient access to individual spatial
objects (have to be collected by
means of joins)
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 639
8.2 Hybrid vs. Integrated Systems
• Example of relational modeling of polygons as a
list of points (see section 4.3)
– Id attribute, list position and integer attributes x, y
– For each polygon the values of
position have to start with value 1
and have to be dense
(implementation of a list)
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 640
8.2 Hybrid vs. Integrated Systems
CREATE TABLE Polygons (CREATE TABLE Polygons (id CHAR(20),position INTEGER,x INTEGER,y INTEGER,PRIMARY KEY (id,position));
• Integrated architecture
– Thematic attributes and spatial data are stored in one
single (geographic) database
– Database functions and GIS
functionality in one system
– Database functions support the
processing of spatial data
– Spatial index structures
– Logical data independence
– Standardization possible
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 641
8.2 Hybrid vs. Integrated Systems
• Example of a query which is possible with
integrated architecture;
typically, this query is
evaluated by using an
R-tree index (see section
4.6 and section 5)
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 642
8.2 Hybrid vs. Integrated Systems
SELECT p.idFROM Parcel p,
WHERE intersects (
SELECT p.idFROM Parcel p,
Brook bWHERE intersects (p.groundPlan,
b.geometry);
• Relational join algorithms aren’t applicable for spatial joins (except Nested Loop)
– Sort-Merge-Join
– No order on spatial (multi-dimensional) data
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 643
8.2 Spatial Join
matNr result
1005 4.0
1005 1.3
2832 5.0
5119 1.7
8676 1.3
9876 3.7
matNr firstName
1005 Clark
2832 Lois
4512 Lex
5119 Charles
6676 Erik
8024 Jean
– Hashjoin
– A hash function, which assigns the same value to
extended, overlapping objects is not known
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 644
8.2 Spatial Join
00
11
22
33
44
55
66
77
00
11
22
33
44
55
66
77
matNr firstName
1005 Clark
2832 Lois
4512 Lex
5119 Charles
6676 Erik
8024 Jean
matNr result
9876 3.7
2832 5.0
1005 4.0
1005 1.3
6676 1.3
5119 1.7
• Spatial join using r-trees
– Suppose the height of both r-trees is the same
– Only MURs on the same level have to be checked for
intersections and only if their parent’s MURs intersect
– A priority queue is used to store the node pairs which
have to be checked
– Filter step of the spatial query evaluation
→ results have to be validated using the original
geometry of the objects
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 645
8.2 Spatial Join
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 646
8.2 Spatial Join
procedure INDEX_TRAVERSAL_SPATIAL_JOIN(rootA, rootB)begin
priorityQueue ← CREATE_PRIORITY_QUEUE();priorityQueue.ADD_PAIR(rootA, rootB);while NOT priorityQueue.EMPTY() do
nodePair ← priorityQueue.POP();rectanglePairs ← FIND_INTERSECTING_PAIRS(nodePair);foreach p Є rectanglePairs do
if p is a pair of leaves thenREPORT_INTERSECTIONS(p);
elsepriorityQueue.ADD_PAIR(p);
endif;enddo;
enddo;end; http://doi.acm.org/10.1145/1206049.1206056
• ADD-PAIR
– Defines the order in which the priority queue is
processed
• Breadth first search
• Breadth first search with additional ordering of the nodes
on one level i.e. x-coordinate or z-address of the MUR’s
center
• Depth first search
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 647
8.2 Spatial Join
1
2
7
3 4
65 9 108
1
2
6
5 8
43 9 107
• Example
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 648
8.2 Spatial Join
1
23
4
5
7
6
8
9
a
b
c
fg h
d
e
i
k
j
l
• R-tree of the rivers
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 649
8.2 Spatial Join
a
bc
fg h
d
e
i
k
j
l
• R-tree of the rivers
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 650
8.2 Spatial Join
II IIII
AA BB CC DD EE
aa cc
bb dd ee
hh ii
jj kk ll
ff gg
a
bc
fg h
d
e
i
k
j
l
AB
C
D E
I
II
• R-tree of the woods
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 651
8.2 Spatial Join
1
23
4
5
7
6
8
9
• R-tree of the woods
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 652
8.2 Spatial Join
1
23
4
5
7
6
8
9
F
G
H
I
III
IV
IIIIII IVIV
FF GG HH II
11 22
33 44
55 66 77
88 99
• 1. iteration
– nodePair: (rootA, rootB)
– priorityQueue: ((II,III) (I,IV) (I,III))
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 653
8.2 Spatial Join
III
IV
I
II
((E,H) (D,H) (I,IV) (I,II))
• 2. iteration
– nodePair: (II, III)
– priorityQueue:
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 654
8.2 Spatial Join
D
E
F
G
H
((i,7) (h,7) (D,H) (I,IV) (I,II))
• 3. iteration
– nodePair: (E,H)
– priorityQueue:
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 655
8.2 Spatial Join
h
i
5
7
6
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 656
8.2 Spatial Join
II IIII
CC AA BB DD EE
aa cc bb dd ee hh iijj kk ll ff gg
IIIIII IVIV
HH GG FF II
11 2233 4455 66 77 88 99
• FIND_INTERSECTING_PAIRS
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 657
8.2 Spatial Join
procedure PLANE_SWEEP(listA, listB)begin
statusA ← CREATE_STATUS()statusB ← CREATE_STATUS()while NOT listA.END() OR NOT listB.END() do
if listA.FIRST() < listB.FIRST() thenstatusA.INSERT(listA.FIRST())statusB.REMOVE_INACTIVE(listA.FIRST())statusB.SEARCH(listA.FIRST())listA.NEXT()
elsestatusB.INSERT(listB.FIRST())statusA.REMOVE_INACTIVE(listB.FIRST())statusA.SEARCH(listB.FIRST())listB.NEXT()
endifenddo
end
f g
5
7
6
statusA:
statusB:
Result:
• Cooperating components– Client initiates the communication
– Client sends requests to the server
– Server provides a fixed set of services
– Roles and functions are asymmetric
– Sequence of interaction steps is determined
– Client may accessmultiple servers
– Server may servemultiple clients
– Server may also beclient when processing a request
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 658
8.3 Clients and Servers
[Da96]
• Various kinds of realising client/server systems
• The differences arise as a result of the partitioning of total functionality
• Possible sub-functions
– Presentationfunction
– Applicationfunction
– Datamanagementfunction
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 659
8.3 Clients and Servers
http://www.it-infothek.de/
• Typical functions of a GIS server
– Selection of thematic and spatial
information from geographic
data base
– Preview of selected spatial data
– Conversion of selected spatial
data into the appropriate target
format
– Cartographic representation of
selected spatial data
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 660
8.3 Servers
http://www.dottedeyes.com/
• Selection of some common GIS Server
– ESRI
• ArcGIS
• ArcIMS
• ArcSDE
– GRASS
– Smallworld
– Oracle Spatial
– Postgres, PostGIS
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 661
8.3 Servers
• ESRI
– Market leader, founded in 1969 as "Environmental Systems Research Institute"
– Chargeable, not open source, Windows and Linux
– Covers the whole range of GIS functionalities
– Products
• ArcGIS - desktop GIS, includes ArcView, ArcEditor, ArcInfo
• ArcView - basic GIS functionality
• ArcEditor - interactive changes
• ArcInfo - full analytical capabilities
• ArcIMS - internet mapserver
• ArcSDE - spatial database engine
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 662
8.3 Servers
• ArcGIS– Complete desktop GIS
• Managing spatial data and metadata
• Editing spatial objects
• Visualizing spatial data
• Selecting spatial objects
• Analyzing of geometric and topological properties
• Import and export of spatial data
• Transformation between coordinate systems
– Interactive interface or callable functions via script language (Python, Perl)
– Based on an object relational database system (meanwhile)
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 663
8.3 Servers
• ArcIMS
– Internet mapserver
– Server application for producing and publishing (interactive) maps on the internet (web mapping)
– Created maps can be visualized by a web browser
– Internal use of XML for communication
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 664
8.3 Servers
http://www.esri.com/
• ArcSDE
– Server application for the management of spatial data
– Middleware as a layer between
the ArcGIS system and a
database system
(e.g. Oracle, DB2)
– All functions of a database
system (e.g. ACID transactions)
– Spatial access structures
(Grid File)
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 665
8.3 Servers
http://www.gisfusion.com/
• GRASS– “Geographic Resources Analysis Support System”
– Free of charge, open source, Linux, Mac OS, Windows
– Offers a variety of GIS functions
• Spatial analysis
• Integrated simulation models
• Geostatistics
• Several projections with transformations
• Map production
• Database connection (Postgres, MySql, Oracle)
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 666
8.3 Servers
– Functions are encapsulated in individual modules
• Approx. 10 modules just
for handling vector
geometry, e.g. for adding
or deleting individual
points in polylines
– Grass consists of more than 400 programs and tools
– Grown system
– Somewhat uncomfortable to use
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 667
8.3 Servers
http://linuxgazette.net/
• Smallworld
– Product of General Electric (now)
– Market leader in the area of network information systems
– Chargeable, not open source, Windows and Linux
– Professional system for companies and authorities
– Focus on user interface, easy in training, scalability
– Various specialized application modules available from third party developers
• Pipeline
• ALKIS, zoning map, land development plan
• Environmental atlas
• District heating, supply line network
• Electricity, gas, water
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 668
8.3 Servers
• Oracle Spatial
– Spatial extension of the Oracle database system(see sections 4.5, 7.3)
– Chargeable, not open source, Windows, MacOS, Linux
– Set of functions for handling spatial data
• Insert, update, delete, select
• Spatial accessstructures
– Specific geometricdata typeSDO_GEOMETRY
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 669
8.3 Servers
• MapViewer
– Additional
component
for rendering
spatial data
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 670
8.3 Servers
http://www.oracle.com/
• Postgres
– Relational database system with spatial data types and corresponding SQL extensions (see sections 4.5, 7.2)
– Free, open source, Linux, MacOS, Windows
– Following data types are offered
• point (float, float)
• box (point, point)
• lseg (point, point)
• line (point1, point2, ..., pointn)
• polygon (point1, point2, ..., pointn)
• circle (point, float)
– Numerous geometric predicates and functions
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 671
8.3 Servers
• PostGIS is an extension of Postgres (Postgres is designed to be extensible)
– Additional data types: MultiPoint, MultiLinestring, MultiPolygon, GeometryCollection
– Syntactic embedding of the new data types is different because they are realized as user-defined types
– First a table is defined
CREATE TABLE ...
then a column with a new data typeis added
SELECT AddGeometryColumn (...)
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 672
8.3 Servers
• OpenJUMP is a “unified mapping platform” fitting
to PostGIS
– Editor
– SVG export
– Layer
concept
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 673
8.3 Servers
http://jump-project.org/
• Typical functions of a GIS client
– Data acquisition, digitization
– Transformations
– Functions for image processing
– Basic CAD functions
– Constructing of spatial objects
– Data reduction, smoothing, generalization
– User interface
– Presentation of data
– Data output
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 674
8.3 Clients
http://www.ikg.uni-hannover.de/
http://www.dgfk.net/
• GIS clients are primarily visualisation tools (map viewer, gis viewer)
• Usually they display spatial data or maps via a web browser
• E.g. the OGC Web MapServices are realised– OGC WMS Viewer company:
Intergraph
– mapClient company: con terra
– ArcExplorer WebESRI
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 675
8.3 Clients
http://www.cardogis.com/
• Intergraph OGC WMS Viewer
– “Thin Client”, web application
– Can connect to web servers which provide the OGC Web Map Services
– Loads maps and displays them
– Can combine different maps
– Contains configurableGUI
– Requires local database server to store and loaded maps
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 676
8.3 Clients
http://www.demis.nl/
• con terra mapClient– Configurable web
application
– Display, navigation,selection, managementof• OGC WMS and WFS
services
• ArcIMS and ArcGISservices
– Measurement of distances and areas
– Drawing of points, lines, and surfaces
– Can be upgraded with further components to a GIS server
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 677
8.3 Clients
http://www.conterra.de/de/
• ESRI ArcExplorer Web
– Browser-based mapping application
– Can access ArcIMS services and OGC WMS Web Map Service
– Combination of
different maps
or layers
– Search for locations
worldwide
– Address search (U.S.)
– Works without any
plug-in or applet
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 678
8.3 Clients
http://www.esri-germany.de/
• Collection of spatial data is particularly expensive
• Spatial data is durable
• Geoservices are increasingly offered by the internet
• Typical keyword: "Internet GIS"
– Internet GIS applications reachmany users
– Requirement for internet clientsare low
– Standards enable simpleexchanges
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 679
8.4 Web-based Spatial Databases
• Application areas of internet-GIS
– Simple information systems
• Standard internet environment with usual plug-ins
• Presentation of interactive maps
• E.g. in the local area for publication of information to
citizens and
visitors
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 680
8.4 Web-based Spatial Databases
http://www.braunschweig.de/
– Specialized georeferenced information systems
• Additional services to the public or for a restricted group of
people
• Dynamical systems needed, since data is processed during
request
• E.g. address search,
route planner
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 681
8.4 Web-based Spatial Databases
http://maps.google.de/
– Web-based GIS clients with access to key resources
• Offer advanced functionalities
• Analysis and intersection of spatial data
• Export and update of attributes
• Used mostly in spatial data infrastructures, because user
training is required
– Portals for spatial data
• For providing and selling of large
quantities of data
• Usually data is supplied by different
spatial data servers
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 682
8.4 Web-based Spatial Databases
http://cdl.niedersachsen.de/
• Internet GIS components
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 683
8.4 Web-based Spatial Databases
[KZe07]
• Technical options for internet GIS
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 684
8.4 Web-based Spatial Databases
setting server client remark
statical
websites
HTML documents, graphic
objects
web browser proven feasible and easy
solution
interactive
websites
HTML documents, graphics
objects, extensive embedded
functionalities
web browser with
script support
needed for larger amounts of
and changing selections of data
client
application
HTML documents with
embedded software components,
data files
web browser with
plug-ins such as SVG,
Java, special viewer
with high demands on
presentation, scalability, and
interaction
dynamic
websites
dynamic server application, direct
access to spatial data
web browser independence from the client,
large amounts of data, and a
variety of functions
spatial data
infrastructure
data services which provide
spatial data via pre-defined
interfaces
spatial client, for
example, viewer, web
portal, desktop GIS
access to distributed spatial
databases
terminal
server
high performance server with
terminal suite, GIS software, and
spatial data
special client full access to a desktop GIS via
internet
• OpenStreetMap (OSM) is a free editable
map of the whole world
• Founder: Steve Coast
• Established: August 9, 2004
• Funding: Entirely by donations
• Licensing model: Creative Commons Attribution-
ShareAlike 2.0
• Mission: To map the world and give the data away
for free
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 685
8.4 Open Street Map
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 686
8.4 Open Street Map
www.openstreetmap.org
• Provide an Open Platform
– OSM Users may freely input and extract data
• Raw sources for OSM Basemap
– GPS track logs
– Existing Free Data Sources (e.g. TIGER/LINE)
– Historical Maps – Out of Copyright mapping
• Users Create Basemap from Raw Sources
– Via Online and Offline Editing Software
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 687
8.4 Open Street Map
• OSM's data is made up from the following elements:
– Nodes: The dots that are used to mark specific locations
(such as a post box) or for drawing segments between.
– Ways: An ordered list of nodes, displayed as connected by
line segments. They are used to describe roads, paths etc.
– Closed Ways: Closed ways are ways which go in a
complete loop. They are used to describe areas like parks,
lakes or islands
– Relations: Basically groups of objects in which each object
may take on a specific role
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 688
8.4 Open Street Map
• Tags
– Key=value pairs
– Can be assigned to OSM-elements i.e. nodes, ways and
relations
– No content restrictions, but they have to be verifiable
– Recommended set of features and corresponding tags
• in order to create, interpret and display a common basemap
• Not every recommended feature will be rendered
• Some rendered Features are not listed
– Possibility to propose new features/icons
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 689
8.4 Open Street Map
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 690
8.4 Open Street Map
Key Value Element Comment Rendering Photo
highway motorway A restricted access major divided highway, normally with 2 or more running lanes plus emergency hard shoulder. Equivalent to the Freeway, Autobahn, etc..
highway trunk_link The link roads (sliproads/ramps) leading to/from a trunk road from/to a trunk road or lower class highway.
highway pedestrian For roads used mainly/exclusively for pedestrians/shopping areas. Also for tagging squares and plazas (in which case, add area=yes.
highway steps For flights of steps (stairs) on footways. Use with step_count=* to indicate the number of steps
http://wiki.openstreetmap.org/wiki/Map_Features
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 691
8.4 Open Street Map
Key Value Element Comment Rendering Photo
amenity university A University campus or buildings
amenity grit_bin A container that hold grit or a mixture from salt and grit.
landuse vineyard A piece of land where grapes are grown.
access yes/ designated/ official/ private/ permissive/ destina-tion/ delivery/ agricultural/ forestry/ unknown/ no
General access permission. - permissive means there is no legally-enshrined right of access, but the landowner has allowed it at his/her discretion - private ….
http://wiki.openstreetmap.org/wiki/Map_Features
• GPS-Traces
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 692
8.4 Open Street Map
File name:GPSDATA_20100113.gpx (download)
Upload:Wednesday, 13. Januar 2010, 11:45 Uhr
Points: 3,162
Coordinate ofstarting point:
-37.8654; 144.695(Map /edit)
owner: Pegaxs
Description: Bike ride
Tags: none
Visibility:Identifiable (list ofordered points with time stamp)
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 693
8.4 Open Street Map
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 694
8.4 Open Street Map
• Database Schema
– 16 administrative tables
– 3 GPX tables
– 2 changesets tables
– 17 geodata tables
• 8 master tables, containing all previous edit history
• 8 current tables, latest revision, used for drawing the map
• 1 table for storing mbrs of countries
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 695
8.4 Open Street Map
• OpenStreetMap stats report (13.01.2010)
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 696
8.4 Open Street Map
users GPS points nodes ways relations users editing gpx files/nodes
day week month
203726 1357120640 530020786 39265159 327997 206/1350 1096/4613 2912/9768
http://wiki.openstreetmap.org/wiki/Stats
05.200609.2006
• Isle of Wight
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 697
8.4 Open Street Map
01.2010
• Export
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 698
8.4 Open Street Map
…
…
• GIS to collect, manage, analyze, display spatial data
– Specialized information system
– Spatial database, spatial database system
– Application software
• GIS hardware and software
– Special input devices
– Digitizer
– Drum scanner
– Classification of GIS software
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 699
8.5 Summary
• Hybrid vs. integrated systems
– File based architecture
– Hybrid architecture
– Layer-oriented architecture
– Integrated architecture
– Detour [spatial join with R-tree index]
• Clients and Servers
– Various kinds of realising client/server systems
– Typical functions of a GIS server/client
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 700
8.5 Summary
• Servers
– ESRI; ArcGIS, ArcIMS, ArcSDE
– GRASS
– Smallworld
– Oracle Spatial
– Postgres, PostGIS
• Clients
– Intergraph OGC WMS Viewer
– con terra mapClient
– ESRI ArcExplorer Web
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 701
8.5 Summary
• Web-based spatial databases
– Internet GIS
– Application areas of internet GIS
– Internet GIS components
– Detour [Open Street Map]
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 702
8.5 Summary
Spatial Databases and GIS – Karl Neumann, Sarah Tauscher– Ifis – TU Braunschweig 703
8.5 Summary
GIS
internetGIS
software
hardware
client/server
systemarchitectures