1Ppmdist User Manual(0) Ppmdist User Manual(0)
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6 ppmdist - simplistic grayscale assignment for machine generated, color
7 images
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11 ppmdist
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13 [-intensity|-frequency]
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15 [ppmfile]
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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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40 In addition to the options common to all programs based on libnetpbm
41 (most notably -quiet, see
42 Common Options ⟨index.html#commonoptions⟩ ), ppmdist recognizes the
43 following command line options:
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47 -frequency
48 Sort input colors by the number of times a color appears in the
49 input, before mapping to evenly distributed graylevels of out‐
50 put.
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53 -intensity
54 Sort input colors by their grayscale intensity, before mapping
55 to evenly distributed graylevels of output. This is the
56 default.
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62 ppmtopgm(1), ppmhist(1), ppm(1)
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66 Copyright (C) 1993 by Dan Stromberg.
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69 This manual page was generated by the Netpbm tool 'makeman' from HTML
70 source. The master documentation is at
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72 http://netpbm.sourceforge.net/doc/ppmdist.html
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74netpbm documentation 22 July 1992 Ppmdist User Manual(0)