; Open Source tools for geospatial tasks - Some alternatives to
Documents
Resources
Learning Center
Upload
Plans & pricing Sign in
Sign Out
Your Federal Quarterly Tax Payments are due April 15th Get Help Now >>

Open Source tools for geospatial tasks - Some alternatives to

VIEWS: 4 PAGES: 15

  • pg 1
									                 Open Source software
                      Geospatial tools




Open Source tools for geospatial tasks
Some alternatives to commercial software packages


   Daniel Ricard (ricardd@mathstat.dal.ca)

                            Graduate Student
                          Department of Biology
                           Dalhousie University

     Workshop on Inshore Ecosystems and Significant Areas of the Scotian Shelf
                  Bedford Institute of Oceanography 2006-01-19




                         Daniel Ricard      Open Source geospatial tools
                                           What is it?
                   Open Source software
                                           More info?
                        Geospatial tools
                                           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



                           Daniel Ricard   Open Source geospatial tools
                                            What is it?
                    Open Source software
                                            More info?
                         Geospatial tools
                                            Examples


For further details

      GNU - GNU is not UNIX
      http://www.gnu.org

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

      Open Source Initiative - Software development model
      http://www.opensource.org/

      Subversion - version control tool
      http://subversion.tigris.org

                            Daniel Ricard   Open Source geospatial tools
                                           What is it?
                   Open Source software
                                           More info?
                        Geospatial tools
                                           Examples


Examples of OSS

     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
         ...

                           Daniel Ricard   Open Source geospatial tools
                                            Software development librairies
                    Open Source software    Spatial databases
                         Geospatial tools   Graphing, mapping and geostatistics
                                            Dedicated GIS


What is special about geo-referenced data?

      Perform a pelagic trawl survey tow at location 297.65347
      43.03456 -50

      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


                            Daniel Ricard   Open Source geospatial tools
                        Software development librairies
Open Source software    Spatial databases
     Geospatial tools   Graphing, mapping and geostatistics
                        Dedicated GIS




        Daniel Ricard   Open Source geospatial tools
                                            Software development librairies
                    Open Source software    Spatial databases
                         Geospatial tools   Graphing, mapping and geostatistics
                                            Dedicated GIS


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)


                            Daniel Ricard   Open Source geospatial tools
                                      Software development librairies
              Open Source software    Spatial databases
                   Geospatial tools   Graphing, mapping and geostatistics
                                      Dedicated GIS


JTS Topology Suite (JTS) - spatial predicates and functions
for fundamental geometric operations
http://www.jump-project.org

GEOS - same as JTS, for the C++ computer language
http://geos.refractions.net/

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

gdal (geospatial data abstraction library) - conversions
between different file formats, both for raster and vector data
http://www.remotesensing.org/gdal/

shapelib - write and edit ESRI shapefile
http://shapelib.maptools.org/
                      Daniel Ricard   Open Source geospatial tools
                                      Software development librairies
              Open Source software    Spatial databases
                   Geospatial tools   Graphing, mapping and geostatistics
                                      Dedicated GIS




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 - http://postgis.refractions.net/
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
    http://www.epsg.org/

                      Daniel Ricard   Open Source geospatial tools
                                         Software development librairies
                 Open Source software    Spatial databases
                      Geospatial tools   Graphing, mapping and geostatistics
                                         Dedicated GIS


specifications for geographic coordinate system


  GEOGCS["WGS 84",
      DATUM["WGS_1984",
          SPHEROID["WGS 84",6378137,298.257223563,
              AUTHORITY["EPSG",7030]],
          TOWGS84[0,0,0,0,0,0,0],
          AUTHORITY["EPSG",6326]],
      PRIMEM["Greenwich",0,AUTHORITY["EPSG",8901]],
      UNIT["DMSH",0.0174532925199433,AUTHORITY["EPSG",9108]],
      AXIS["Lat",NORTH],
      AXIS["Long",EAST],
      AUTHORITY["EPSG",4326]]


                         Daniel Ricard   Open Source geospatial tools
                                         Software development librairies
                 Open Source software    Spatial databases
                      Geospatial tools   Graphing, mapping and geostatistics
                                         Dedicated GIS


specifications for projected coordinate system

  PROJCS["UTM 17 (WGS84) in northern hemisphere.",
      GEOGCS["WGS 84",
          DATUM["WGS_1984",
              SPHEROID["WGS 84",6378137,298.257223563,
                  AUTHORITY["EPSG",7030]],
              TOWGS84[0,0,0,0,0,0,0],
              AUTHORITY["EPSG",6326]],
          PRIMEM["Greenwich",0,AUTHORITY["EPSG",8901]],
          UNIT["DMSH",0.0174532925199433,AUTHORITY["EPSG",910
          AXIS["Lat",NORTH],
          AXIS["Long",EAST],
          AUTHORITY["EPSG",4326]],
      PROJECTION["Transverse_Mercator"],
      PARAMETER["latitude_of_origin",0],
      PARAMETER["central_meridian",-81],
                         Daniel Ricard   Open Source geospatial tools
                                      Software development librairies
              Open Source software    Spatial databases
                   Geospatial tools   Graphing, mapping and geostatistics
                                      Dedicated GIS




Generic Mapping Tools (GMT) - ~ 60 tools to produce plots
and maps in postscript format
http://gmt.soest.hawaii.edu/



The R project for statistical computing and its software
environment for statistics and graphics
http://www.r-project.org
    maps, mapproj and mapdata - R packages for mapping
    gstat - R package that implements functions for analysis of
    spatial correlation
    http://www.gstat.org/



                      Daniel Ricard   Open Source geospatial tools
                                            Software development librairies
                    Open Source software    Spatial databases
                         Geospatial tools   Graphing, mapping and geostatistics
                                            Dedicated GIS


GIS

      Open geospatial consortium
          Adopted specifications for GIS technology
      http://www.opengeospatial.org/

      GRASS - a complete GIS package
      http://grass.itc.it/
      Quantum GIS - improved GUI, but less features (still young)
      http://www.qgis.org/
      uDig - Java-based, basic capabilities
      http://udig.refractions.net/


                            Daniel Ricard   Open Source geospatial tools
Open Source software
     Geospatial tools




        Daniel Ricard   Open Source geospatial tools
                   Open Source software
                        Geospatial tools



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 1.0.4 on PostgreSQL 8.0.4 with GEOS 2.1.4 and proj
         4.4.9 libraries
         Quantum GIS 0.7.3


                           Daniel Ricard   Open Source geospatial tools

								
To top