http://onionworks.net/2006/imageservice
getPixelIndex (workspace : nodeset, x : number, y : number) : nodeset
With this method, the colour palette index of the colour at a certain pixel can be determined.
The syntax of the method can be seen in the following example. The used variable “workspace” contains a created workspace.
<xsl:variable name="pixelIndex" select="is:getPixelIndex($workspace,100,100)" />