ppmtopgm(1)             UNIX System V(23 December 1988)             ppmtopgm(1)


NAME
      ppmtopgm - convert a portable pixmap into a portable graymap

SYNOPSIS
      ppmtopgm [ppmfile]

DESCRIPTION
      Reads a portable pixmap as input.  Produces a portable graymap as output.
      The quantization formula used is .299 r + .587 g + .114 b.

      Note that although there is a pgmtoppm program, it is not necessary for
      simple conversions from pgm to ppm, because any ppm program can read pgm
      (and pbm ) files automagically.  pgmtoppm is for colorizing a pgm file.
      Also, see ppmtorgb3 for a different way of converting color to gray.

QUOTE
      Cold-hearted orb that rules the night
      Removes the colors from our sight
      Red is gray, and yellow white
      But we decide which is right
      And which is a quantization error.

SEE ALSO
      pgmtoppm(1), ppmtorgb3(1), rgb3toppm(1), ppm(5), pgm(5)

AUTHOR
      Copyright (C) 1989 by Jef Poskanzer.



























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