Open Source tools for geospatial tasks

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Bethanie Dalton
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1 Open Source tools for geospatial tasks Some alternatives to commercial software packages Graduate Student Department of Biology Dalhousie University Workshop on Inshore Ecosystems and Significant Areas of the Scotian Shelf Bedford Institute of Oceanography

ca) Graduate Student Department of Biology Dalhousie University Workshop

2 What is it? More info? Examples Free and Open Source Software (OSS) Free Software vs. Open Source Source code is available Free as in Freedom and Free Speech Often free, as in Free Beer Often released under the GNU General Public License (GPL), a.k.a. Copyleft Agreement Not the same as freeware and shareware where source code is not available Version control software is integral to the OSS model

3 For further details Open Source software What is it? More info? Examples GNU - GNU is not UNIX Free Software Foundation Open Source Initiative - Software development model Subversion - version control tool

org Free Software Foundation http://www.fsf.

4 Examples of OSS Open Source software What is it? More info? Examples Linux Operating System Operating system and large number of software packages Runs on multiple architectures (Intel x86, 64-bit PC, PowerPC, SPARC,...) Many different distributions (Red Hat, SuSE, Debian, Slackware,...) Basically, UNIX on a PC, usually for free Other common OSS Cygwin - UNIX tools in Windows Mozilla Firefox web browser R (statistics and graphics) GNU Image Manipulation Program (GIMP) ghostscript and ghostview...

x86, 64-bit PC, PowerPC, SPARC,...) Many different distributions (Red Hat, SuSE, Debian, Slackware,.

5 What is special about geo-referenced data? Perform a pelagic trawl survey tow at location Requires a spatial reference system geographic coordinate system datum - a spheroid prime meridian angular unit projected coordinate system details about the underlying geographic coordinate system details about the transformation between angular and projected positions

03456-50 Requires a spatial reference system geographic coordinate system datum - a spheroid

7 Geographic Information System Handles details about the spatial reference systems and the projections Uses point (e.g. tow location), vector (e.g. closed area boundaries and coastlines) and raster (bathymetry grid) data Database back-end and ability to enter and edit data Graphical user interface Mapping and visualisation capabilities Analytical capabilities (geometry, measurement and analytical functions) Statistical capabilities (analysis of spatial correlation)

back-end and ability to enter and edit data Graphical user interface Mapping and visualisation capabilities

8 JTS Topology Suite (JTS) - spatial predicates and functions for fundamental geometric operations GEOS - same as JTS, for the C++ computer language proj4 - transformations between different projections gdal (geospatial data abstraction library) - conversions between different file formats, both for raster and vector data shapelib - write and edit ESRI shapefile

net/ proj4 - transformations between different projections http://proj.maptools.

9 Relational database management systems processing done in Structured Query Language (SQL) e.g. Oracle, MS Access, DB2, postgresql, mysql,... designed to facilitate the storage, retrieval, sharing and analysis of data numerous data types, including DATETIME OpenGIS Simple Features Implementation Specification for SQL (1999) - geographic data types and spatial operators postgis - EPSG database of spatial reference systems maintained by the International Association of Oil and Gas Producers (OGP) Surveying and Positioning Committee predator of the European Petroleum Survey Group

$Specification for SQL (1999) - geographic data types and spatial operators postgis - http://postgis.refractions.$

10 specifications for geographic coordinate system GEOGCS["WGS 84", DATUM["WGS_1984", SPHEROID["WGS 84", , , AUTHORITY["EPSG",7030]], TOWGS84[0,0,0,0,0,0,0], AUTHORITY["EPSG",6326]], PRIMEM["Greenwich",0,AUTHORITY["EPSG",8901]], UNIT["DMSH", ,AUTHORITY["EPSG",9108]], AXIS["Lat",NORTH], AXIS["Long",EAST], AUTHORITY["EPSG",4326]]

257223563, AUTHORITY["EPSG",7030]], TOWGS84[0,0,0,0,0,0,0], AUTHORITY["EPSG",6326]],

11 specifications for projected coordinate system PROJCS["UTM 17 (WGS84) in northern hemisphere.", GEOGCS["WGS 84", DATUM["WGS_1984", SPHEROID["WGS 84", , , AUTHORITY["EPSG",7030]], TOWGS84[0,0,0,0,0,0,0], AUTHORITY["EPSG",6326]], PRIMEM["Greenwich",0,AUTHORITY["EPSG",8901]], UNIT["DMSH", ,AUTHORITY["EPSG",910 AXIS["Lat",NORTH], AXIS["Long",EAST], AUTHORITY["EPSG",4326]], PROJECTION["Transverse_Mercator"], PARAMETER["latitude_of_origin",0], PARAMETER["central_meridian",-81],

12 Generic Mapping Tools (GMT) - ~ 60 tools to produce plots and maps in postscript format The R project for statistical computing and its software environment for statistics and graphics maps, mapproj and mapdata - R packages for mapping gstat - R package that implements functions for analysis of spatial correlation

edu/ The R project for statistical computing and its software environment for statistics and

13 GIS Open Source software Open geospatial consortium Adopted specifications for GIS technology GRASS - a complete GIS package Quantum GIS - improved GUI, but less features (still young) udig - Java-based, basic capabilities

org/ GRASS - a complete GIS package http://grass.itc.

15 Demo of OSS geospatial tools Linux 2.6 kernel - Ubuntu breezy (Debian-based distribution) little movie of the Scotian Shelf maps made in GMT 4.1b conversion to bitmap images handled by ImageMagick movie file made using mencoder database of DFO and NMFS groundfish surveys and closed areas PostGIS on PostgreSQL with GEOS and proj libraries Quantum GIS 0.7.3

An Introduction to Open Source Geospatial Tools

An Introduction to Open Source Geospatial Tools by Tyler Mitchell, author of Web Mapping Illustrated GRSS would like to thank Mr. Mitchell for this tutorial. Geospatial technologies come in many forms,