ppmtopj

Convert a PPM file to an HP PaintJet file. More information: https://netpbm.sourceforge.net/doc/ppmtopj.html.

ppmtopj path/to/input.ppm > path/to/output.pj

ppmtopj -xpos dx -ypos dy path/to/input.ppm > path/to/output.pj

ppmtopj -gamma gamma path/to/input.ppm > path/to/output.pj