The potential of XML encoding in geomatics converting raster images to XML and SVG

The evolution of open standards and especially those pertaining to the family of XML technologies, have a considerable impact on the way the Geomatics community addresses the acquisition, storage, analysis and display of spatial data. The most recent version of the GML specification enables the merging of vector and raster data into a single “open” format. The notion of “coverage” as described in GML 3.0 can be the equivalent of a raster multi-band dataset. In addition, vector data storage is also described in detail through the GML Schemas and XML itself can store the values of a raster dataset, as values of a multi-table dataset. Under these circumstances an issue that must be addressed is the transformation of raster data into XML format and their subsequent visualization through SVG. The objective of this paper is to give an overview of the steps that can be followed in order to embody open standards and XML technologies in the raster domain. The last part of the work refers to a case study that suggests a step by step methodology to accomplish classification, an important function in Cartography and Remote Sensing, using the XML-encoded images.