The GPD does that 'automatically'. So no way to do that outside of eclipse
What are you trying to do?
The process image is saved in the process archive and can be retrieved from the process definition object.
You can get the process definition object either through the embedded jpdl engine or through the command service interface.
But as the previous poster said it is generated in Eclipse and uploaded with the process archive.
Folks on this board have posted some jsp stuff to generate the image by iterating through the process graph.