1Pgmtopbm User Manual(0)                                Pgmtopbm User Manual(0)
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NAME

6       pgmtopbm - convert a PGM image to PBM
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SYNOPSIS

10       pgmtopbm
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12       [-floyd  |  -fs  | -threshold | -hilbert | -dither8 | -d8 | -cluster3 |
13       -c3 | -cluster4 | -c4 | -cluster8 | -c8]
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15       [-value val]
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17       [-clump size]
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19       [-randomseed integer]
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21       [pgmfile]
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DESCRIPTION

25       This program is part of Netpbm(1).
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27       This program is almost  entirely  obsolete  since  Netpbm  10.23  (July
28       2004).  Use pamditherbw(1) to do what this program used to do.
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30       pgmtopbm  never  was  the simple converter it appeared to be.  It was a
31       dithering program.  Unfortunately, it didn't do the dithering  properly
32       because  it treated the PGM input samples as if they were directly pro‐
33       portional to light intensity, but they are actually gamma-adjusted.
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35       pamditherbw is backward compatible with pgmtopbm except that it
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38       ·      does the correct gamma adjustments.
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40       ·      produces PAM output instead of  PBM.   (Modern  Netpbm  programs
41              that  accept  PBM  input  also accept PAM input, but if you need
42              actual PBM, you can use pamtopnm with pamditherbw).
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44              So use the manual for pamditherbw for  pgmtopbm,  except  ignore
45              anything  that  says it was added after Netpbm Release 10.23 and
46              ignore any options that are not shown in the synopsis above.
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48       Although pgmtopbm is  mostly  obsolete,  the  simple  threshold  method
49       (specified by -threshold) is an exception.  Unlike the other conversion
50       methods, gamma-adjustment is not an issue with simple thresholding  and
51       pgmtopbm can produce PBM output directly.  Note that even in this basic
52       mode of operation pgmtopbm may produce output which is slightly differ‐
53       ent  from what pamditherbw does because of differences in internal cal‐
54       culation.
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56       If you just want to convert a PGM image with maxval 1 to PBM, use  pam‐
57       topnm(1).
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SEE ALSO

61       pamditherbw(1),   pamtopnm(1),   pbmtopgm(1),  pamthreshold(1),  pbmre‐
62       duce(1), pgm(1), pbm(1)
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AUTHOR

66       Copyright (C) 1989 by Jef Poskanzer.
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DOCUMENT SOURCE

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/pgmtopbm.html
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74netpbm documentation             17 July 2020          Pgmtopbm User Manual(0)
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