Manual: ppmdither

Ppmdither User Manual(1)			   General Commands Manual			    Ppmdither User Manual(1)

NAME
       ppmdither - ordered dither for color images

SYNOPSIS
       ppmdither

       [-dim=power]

       [-red=n]

       [-green=n]

       [-blue=n]

       [netpbmfile]

       All  options can be abbreviated to their shortest unique prefix.	 You may use two hyphens instead of one to designate
       an option.  You may use either white space or an equals sign between an option name and its value.

DESCRIPTION
       This program is part of Netpbm(1).

       ppmdither reads a Netpbm image as input, and applies dithering to it to reduce the number of colors used down to	 the
       specified number of shades for each primary.  It produces a PPM image as output.

       The default number of shades is 5 red, 9 green, and 5 blue, for a total of 225 colors.  To convert the image to a bi‐
       nary rgb format suitable for primitive color printers, use -red=2 -green=2 -blue=2.

       You can do another kind of dither -- Floyd-Steinberg -- with pnmquant or pnmremap.

OPTIONS
       In addition to the options common to all programs based on libnetpbm (most notably -quiet, see  Common Options ), pp‐
       mdither recognizes the following command line 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=n The number of red shades to be used, including black; minimum of 2.

	      Default is 5.

       -green n
	      The number of green shades to be used, including black; minimum of 2.

	      Default is 9.

       -blue n
	      The number of blue shades to be used, including black; minimum of 2.

	      Default is 5.

SEE ALSO
       pamditherbw(1), pamdepth(1), pnmquant(1), pnmremap(1), ppm(1)

AUTHOR
       Copyright (C) 1991 by Christos Zoulas.

DOCUMENT SOURCE
       This manual page was generated by the Netpbm tool 'makeman' from HTML source.  The master documentation is at

	      http://netpbm.sourceforge.net/doc/ppmdither.html

netpbm documentation				      16 December 2009				    Ppmdither User Manual(1)