Section: User Commands (1)
Updated: 14 July 1991Index
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ppmdither - ordered dither for color images
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
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.
- -dim power
The size of the dithering matrix. The dithering matrix is a square whose
dimension is a power of 2.
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, including 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.
Copyright (C) 1991 by Christos Zoulas.
- SEE ALSO