ppmcolormask(1)             General Commands Manual            ppmcolormask(1)

       ppmcolormask - produce mask of areas of a certain color in a PPM file

       ppmcolormask color [ppmfile]

       Reads  a  PPM  file  as input.  Produces a PBM (bitmap) file as output.
       The output file is the same dimensions as the input file and  is  black
       in all places where the input file is the color color, and white every-
       where else.

       The output of ppmcolormask is useful as an alpha mask input to pnmcomp.
       Note that you can generate such an alpha mask automatically as you con-
       vert to PNG format with pnmtopng(1).  Use its -transparent option.

       ppmfile is the input file.  If you don't specify ppmfile, the input  is
       from Standard Input.

       The output goes to Standard Output.

       You can specify color five ways:

       o      An X11-style color name (e.g.  black).

       o      An  X11-style  hexadecimal specifier: rgb:r/g/b, where r g and b
              are each 1- to 4-digit hexadecimal numbers.

       o      An X11-style decimal specifier: rgbi:r/g/b, where r g and b  are
              floating point numbers between 0 and 1.

       o      For  backwards  compatibility, an old-X11-style hexadecimal num-
              ber: #rgb, #rrggbb, #rrrgggbbb, or #rrrrggggbbbb.

       o      For backwards compatibility, a triplet of numbers  separated  by
              commas:  r,g,b,  where  r  g  and  b  are floating point numbers
              between 0 and 1.  (This style was added before MIT came up  with
              the similar rgbi style.)

       pgmtoppm(1), pnmcomp(1), pbmmask(1), ppm(5)

       Bryan Henderson (bryanh@giraffe-data.com)

                                 14 April 2000                 ppmcolormask(1)
Man Pages Copyright Respective Owners. Site Copyright (C) 1994 - 2022 Hurricane Electric. All Rights Reserved.