ppmtomap - extract all colors from a portable pixmap
ppmtomap [__-sort__? [__-square__?
Reads a portable pixmap as input. Produces a portable pixmap
as output, representing a color map of the input file. All N
different colors found are put in an Nx1 portable pixmap.
This color map file can be used as a mapfile for
ppmquant or ppmtogif.
Produces a portable pixmap with the colors in some sorted
Produces a (more or less) square output file, instead of
putting all colors on the top row.
All flags can be abbreviated to their shortest unique
If you want to use the output file as a mapfile for
ppmtogif, you first have to do a ppmquant 256,
since ppmtomap is not limited to 256 colors (but to
ppmtogif(1)?, ppmquant(1), ppm(5)
Marcel Wijkstra (email@example.com).
Copyright (C) 1989 by Jef Poskanzer.