GeoExpress allows Geography Markup Language (GML) metadata to be added to JPEG 2000 (JP2) imagery to comply with the Open Geospatial Consortium (OGC) GMLJP2 standard.
GML (Geography Markup Language) is an open, XML-based specification for representing geographic information including geographic features, coverages, observations, topology, geometry, coordinate reference systems, units of measure, time and other values. Because it is an XML grammar, it is both extensible and adaptable to any application within the broad geospatial field.
As a wavelet-based image compression format, JPEG 2000 (JP2) is capable of handling images into the gigabyte range and beyond. But until recently, JP2 was not particularly suited to the needs of the geospatial community because it didn't have a designated geospatial metadata standard. However, because the JPEG 2000 format allows for the inclusion of XML data, GML has emerged as the ideal partner for JPEG 2000 imagery, bridging the gap between JP2 and GIS.
GMLJP2 is the specification that standardizes that partnership and opens the door for greater interoperability between your imagery and the thousands of current and future geospatial applications that might use it. Containing its own geographic metadata, your JP2 imagery becomes "spatially aware" and is thus of increased value in geospatial applications. Prior to the adoption of GMLJP2, the lack of a geospatial metadata standard meant that applications and viewers may or may not have been able to read geospatial metadata in a JPEG 2000 file.
The GMLJP2 specification was officially adopted in February 2006 by the Open Geospatial Consortium (OGC) as an open standard for representing geographic information in JPEG 2000 imagery. LizardTech supports open standards and is committed to the success of the GMLJP2 specification.
Jointly proposed and developed by LizardTech, Galdos Systems and a consortium of forward-looking aerospace and technology companies, GMLJP2 represents the most advanced means of including geographic metadata within compressed geospatial imagery and making that information useful in downstream applications now and in the future.
GeoExpress already offers the most complete and easy-to-use implementation of the open JPEG 2000 standard. Now, your JP2 imagery encoded with GMLJP2 metadata is secure for the future because, like JPEG 2000, the GMLJP2 specification is an open, non-proprietary standard.
NOTE: Some applications that support JPEG 2000 do not support all of the features that are required to implement the GMLJP2 standard. For more information, see About GML and GMLJP2.
The GML option is available among the metadata control settings of the advanced JPEG 2000 encode options.
Learn more about the GML and GMLJP2 specifications at http://www.opengeospatial.org/specs/?page=specs.
The GMLJP2 Application Schema version 3.1.1. can be found at http://schemas.opengis.net/gml/.