1 / 15

The OpenGIS Consortium Geog 516 Presentation #2

The OpenGIS Consortium Geog 516 Presentation #2. Rueben Schulz March 2004. Overview. The OpenGIS Consortium Specifications Benefits Issues Impact and Examples. The OpenGIS Consortium. Non-profit trade association (1994) Develop geoprocessing interoperability standards

emlyn
Download Presentation

The OpenGIS Consortium Geog 516 Presentation #2

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. The OpenGIS ConsortiumGeog 516 Presentation #2 Rueben Schulz March 2004

  2. Overview • The OpenGIS Consortium • Specifications • Benefits • Issues • Impact and Examples

  3. The OpenGIS Consortium • Non-profit trade association (1994) • Develop geoprocessing interoperability standards • Grew out of interoperability initiatives in the GRASS community • 257 Members, include: • Government • Industry • Universities • Similar to W3C and ISO

  4. Vision “A world in which everyone benefits from geographic information and services made available across any network, application, or platform.”

  5. Specifications • Simple Features (Vectors) • Grid Coverages (Rasters) • Coordinate Transformation Services (CTS) • Geography Markup Language (GML) • Filter Encodings • Styled Layer Descriptor (SLD) • Web Map Services (WMS) • Web Feature Service (WFS) • Web Coverage Service (WCS) • Web Map Context Documents • Catalogue Interface (CAT) • Location Services

  6. Simple Features (Vector) • Specification currently version 1.1 • Defines a set of basic geometry types: • Point, line, polygon, multi-point, multi-line, multi-polygon, multi-geometry • Defines operations on these • Includes ways of storing geometries and features • WKT, WKB, GML • Work on a new abstract specification • ISO-19107 (an ISO partnership) • Lots of different geometries (not simple) • 3D shapes, surfaces, TINs, and many more

  7. Simple Features Con’t

  8. Grid Coverages (Raster) • Defines interfaces for: • accessing, analyzing and processing raster datasets • Grid coverage can generate a value for any point in its domain. • May be backed by a: • Set of polygons that cover entire area • Grid of values (traditional raster) • Mathematical function

  9. Coordinate Transformations • Describes Coordinate Reference System‘s (CRS) and general methods to convert between them. • Also specifies ways of storing these objects as text • Well Known Text (WKT) and XML • WKT example: GEOGCS["WGS 84", DATUM["WGS_1984",SPHEROID["WGS 84",6378137,298.257223563],TOWGS84[0,0,0,0,0,0,0], PRIMEM["23W",23],UNIT["DMSH",0.0174532925199433], AXIS["Long",EAST],AXIS["Lat",NORTH]] • Compliments efforts by European Petroleum Survey Group (EPSG) • New specification underway (ISO – 19111)

  10. Web GIS Standards • Standard protocols for: • Web Map Services (WMS) • Sends images of maps across the web • Useful for base maps, but does not give access to underlying data • Web Feature Service (WFS) • Sends vector geometries (GML), can do analysis / editing on these • Web Coverage Service (WCS) • Sends rasters (grid coverage), can do analysis on these

  11. Benefits • Users can easily move between vendors • Data interchange • Concepts about GIS/RS the same; single set of terms and definitions • Efficient and share R&D - best minds from many different industries can meet and work. • Document ideas for other people to learn from • Can advance state of the art or increase completeness of a product • Increase competition and innovation

  12. Issues • Specifications need to be implemented to be of any benefit • Vendors have products implemented before specification • Specification may need to be extended in incompatible ways to do everything vendor wants now • Bad for large companies • Makes it easier for users to change vendors • Removes some competitive advantage • Specifications keep changing

  13. Impact and Examples • US Geospatial 1 Stop Portal - WMS, WFS, CAT • Canadian GeoConnections Discovery Portal - WMS, WFS, CAT • ESRI’s ArcGIS - Simple Features, Spatial References • OGC Imperoperability Addon to support GML, WMS, WFS • PostGIS, ArcSDE, Oracle Spatial, and IBM DB2 - support Simple Features for SQL • Java Topology Suite (JTS) – Simple Features • GeoTools2 – “leading open source Java library for developing OpenGIS solutions” • MapServer – WMS • GeoServer – WMS and reference implementation for WFS • ESRI’s ArcIMS - WMS and WFS through an addon

  14. Impact and Examples con’t

  15. References • DigitalEarth.Org “OGC December Meeting Summary” at http://digitalearth.org/story/2002/12/12/143552/20 • ESRI “GIS Standards and Interoperability” at http://www.esri.com/software/opengis/index.html • Federal Computer Week "Interior e-gov tack irks GIS vendors: GIS Consortium, vendor work on parallel tasks“ at http://www.fcw.com/fcw/articles/2003/0414/news-gis-04-14-03.asp • The OpenGIS Consortium at http://www.opengis.org

More Related