1Ppmdist User Manual(0)                                  Ppmdist User Manual(0)
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NAME

6       ppmdist  - simplistic grayscale assignment for machine generated, color
7       images
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SYNOPSIS

11       ppmdist
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13       [-intensity|-frequency]
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15       [ppmfile]
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DESCRIPTION

19       This program is part of Netpbm(1).
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21       ppmdist reads a PPM image as input and performs a simplistic  grayscale
22       assignment intended for use with grayscale or bitmap printers.
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24       Often  conversion from ppm to pgm will yield an image with contrast too
25       low for good printer output.  The program  maximizes  contrast  between
26       the gray levels output.
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28       A ppm input of n colors is read, and a pgm of n gray levels is written.
29       The gray levels take on the values 0..n-1, while maxval takes on n-1.
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31       The mapping from color to stepped grayscale can be performed  in  order
32       of  input  pixel intensity, or input pixel frequency (number of repeti‐
33       tions).
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35       This program is helpful only for images with a  very  small  number  of
36       colors.
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OPTIONS

41       -frequency
42              Sort  input colors by the number of times a color appears in the
43              input, before mapping to evenly distributed graylevels  of  out‐
44              put.
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47       -intensity
48              Sort  input  colors by their grayscale intensity, before mapping
49              to  evenly  distributed  graylevels  of  output.   This  is  the
50              default.
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SEE ALSO

56       ppmtopgm(1), ppmhist(1), ppm(1)
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AUTHOR

60       Copyright (C) 1993 by Dan Stromberg.
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64netpbm documentation             22 July 1992           Ppmdist User Manual(0)