ppmdither(1)ppmdither(1)NAMEppmdither - ordered dither for color images
SYNOPSISppmdither [-dim power] [-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 speci
fied number of shades for each primary. The default num
ber 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.
OPTIONS-dim power The size of the dithering matrix. The
dithering matrix is a square whose dimension
is a power of 2. power is that power of 2.
The default is 4, for a 16 by 16 matrix.
-red shades The number of red shades to be used, includ
ing black; minimum of 2.
-green shades The number of green shades to be used,
including black; minimum of 2.
-blue shades The number of blue shades to be used,
including black; minimum of 2.
SEE ALSOpnmdepth(1), ppmquant(1), ppm(5)AUTHOR
Copyright (C) 1991 by Christos Zoulas.
14 July 1991 ppmdither(1)