This program is part of Netpbm.
gemtopnm reads a GEM .img file, either the one plane (black/white) or four plane (16 color) varieety, as input and produces a PBM or PPM file as output, depending on whether the input is one or four plane.
The input file is gemfile if you specify that argument, or Standard Input otherwise. Output is to Standard Output.
Copyright (C) 1988 Diomidis D. Spinellis (dds@cc.ic.ac.uk).