ppmdither(1)              UNIX System V(14 July 1991)              ppmdither(1)


NAME
      ppmdither - ordered dither for color images

SYNOPSIS
      ppmdither [-dim dimension] [-red shades] [-green shades] [-blue shades]
      [ppmfile]

DESCRIPTION
      Reads a portable pixmap as input, and applies dithering to it to reduce
      the number of colors used down to the specified number of shades for each
      primary.  The default number of shades is red=5, green=9, blue=5, for a
      total of 225 colors.  To convert the image to a binary rgb format
      suitable for color printers, use -red 2 -green 2 -blue 2.  The maximum
      number of colors that can be used is 256 and can be computed as the
      product of the number of red, green and blue shades.

OPTIONS
      -dim dimension
                    The size of the dithering matrix.  Must be a power of 2.

      -red shades   The number of red shades to be used; minimum of 2.

      -green shades The number of green shades to be used; minimum of 2.

      -blue shades  The number of blue shades to be used; minimum of 2.

SEE ALSO
      pnmdepth(1), ppmquant(1), ppm(5)

AUTHOR
      Copyright (C) 1991 by Christos Zoulas.























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