pjtoppm - convert an HP PaintJet file to a PPM image
This program is part of Netpbm(1).
pjtoppm reads an HP PaintJet file as input and converts it into a PPM image. This was a quick hack to save some trees, and it only handles a small subset of the paintjet commands. In particular, it will only handle enough commands to convert most raster image files.
HP PaintJet XL Color Graphics Printer User's Guide