1Ppmdither User Manual(0)                              Ppmdither User Manual(0)
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NAME

6       ppmdither - ordered dither for color images
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SYNOPSIS

10       ppmdither
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12       [-dim power]
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14       [-red shades]
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16       [-green shades]
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18       [-blue shades]
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20       [ppmfile]
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DESCRIPTION

24       This program is part of Netpbm(1).
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26       ppmdither  reads  a  PPM image as input, and applies dithering to it to
27       reduce the number of colors used down to the specified number of shades
28       for  each  primary.   The  default  number of shades is red=5, green=9,
29       blue=5, for a total of 225 colors.  To convert the image  to  a  binary
30       rgb format suitable for color printers, use -red 2 -green 2 -blue 2.
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32       You  can  do another kind of dither -- Floyd-Steinberg -- with pnmquant
33       or pnmremap.
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OPTIONS

37       -dim power
38               The size of the dithering matrix.  The dithering  matrix  is  a
39              square  whose dimension is a power of 2.  power is that power of
40              2.  The default is 4, for a 16 by 16 matrix.
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43       -red shades
44              The number of red shades to be used, including black; minimum of
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48       -green shades
49              The  number of green shades to be used, including black; minimum
50              of 2.
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53       -blue shades
54              The number of blue shades to be used, including  black;  minimum
55              of 2.
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SEE ALSO

60       pamdepth(1), pnmquant(1), pnmremap(1), ppm(1)
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AUTHOR

64       Copyright (C) 1991 by Christos Zoulas.
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68netpbm documentation             14 July 1991         Ppmdither User Manual(0)