pnmquant Man page

pnmquant General Commands Manual pnmquant


pnmquant – quantize the colors in a Netpbm image to a smaller set


pnmquant [-center|-meancolor|-meanpixel] [-floyd|-fs] [-nofloyd|-nofs] [-spreadbrightness|-spreadluminosity] ncolors [pnmfile]

All options can be abbreviated to their shortest unique prefix. You
may use two hyphens instead of one to designate an option. You may use
either white space or equals signs between an option name and its


Reads a PNM image as input. Chooses ncolors colors to best represent
the image, maps the existing colors to the new ones, and writes a PNM
image as output.

This program is simply a combination of pnmcolormap and pnmremap, where
the colors of the input are remapped using a color map which is gener‐
ated from the colors in that same input. The options have the same
meaning as in those programs. See their documentation to understand

It is much faster to call pnmcolormap and pnmremap directly than to run
pnmquant. pnmquant is just a convenience.

ppmquant is an older program which does the same thing as pnmquant, but
on only PPM images. It is, however, faster than either pnmquant or


pnmcolormap, pnmremap, ppmquantall, pnmdepth, ppmdither,
ppmquant, pnm(5)


Written by Bryan Henderson

20 January 2002 pnmquant