Galdos Systems created the INdicio™ CRS Registry, an implementation of the INdicio™ Web Registry, to provide an open standards-based registry of co-ordinate reference systems (CRS) and units of measure definitions.
The INdicio CRS Registry supports any co-ordinate reference system that can be defined using GML v3.2, including the Europoean Petroleum Survey Group (EPSG) reference system, various types of Engineering Reference Systems, and the co-ordinate reference system model defined by the ISO 19111 standard.
EPSG Geodetic Parameter Registry
When Shell Oil and the International Association of Oil & Gas Producers (OGP) wanted to build a new Geodetic Parameter Registry, they selected Galdos INdicio™ as the base technology.
| Problem | Solution |
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There was no way to manage critical coordinate reference systems data (store and retrieve in real-time). The lack of data integration meant that data for important decisions (such as exploration planning) was lacking. |
Galdos delivered an INdicio™ CRS Registry that provided a central and global access point for coordinate reference systems. Users now acquire the most up-to-date CRSs directly from a single source. |
The INdicio CRS Registry is available with the current European Petroleum Survey Group content, or the user can receive updates directly from the International Association of Oil & Gas Producers, who maintain this content.
A configurable AJAX client interface is layered on top of the INdicio CRS Registry to provide support for managing the registry and a variety of modes for retrieving content, including search by identifier, search by location (spatial extent), and search by CRS component type (e.g. Coordinate System, Datum, etc.). Returned results, which may be co-ordinate reference systems or components, are displayed in a flexible and easy-to-read manner.
What is a CRS?
Geographic locations are specified in terms of co-ordinate reference systems. A Co-ordinate Reference System (or Spatial Reference System) defines how geospatial references relate to real objects located on the Earth’s surface.
A co-ordinate reference system combines a Coordinate System, which is a set of mathematical rules that specify how a set of co-ordinates are assigned to a specific point, with a datum, which gives the relationship of the co-ordinate system to the surface and shape of the Earth.
A Datum is a set of parameters that define the point of origin, scale, and orientation of a particular co-ordinate system, and which serves as the basis for calculating other parameters. Each datum can support multiple co-ordinate systems.
Co-ordinates defined in terms of co-ordinate systems that are based on the same datum can be converted between those co-ordinate systems using a one-to-one conversion between parameters that have constant values.
Co-ordinate Transformations
Galdos has developed a number of co-ordinate transformations through our work with the OGP and Shell Oil, and with the Open Geospatial Consortium (OGC). These types of projects draw heavily on our experiences with XML, GML, and Extensible Stylesheet Language Transformations (XSLT).
Transforming co-ordinates between co-ordinate systems that use different datums is more complex than converting between co-ordinate systems that are based on the same datum. To change co-ordinates from one co-ordinate reference system to another that is based on a different datum requires a transformation that uses parameters which are derived from a set of points with known co-ordinates in both co-ordinate reference systems.
The INdicio CRS Registry allows co-ordinate transformations to be associated with the co-ordinate reference systems that they were created to be used with. The EPSG dataset includes a number of these transformations already associated with the related co-ordinate reference systems.
The EPSG publishes a number of guidance notes with information about CRSs and the EPSG Geodetic Parameter Registry and dataset.
