1Pbmclean User Manual(0)                                Pbmclean User Manual(0)
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NAME

6       pbmclean - flip isolated pixels in portable bitmap
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SYNOPSIS

10       pbmclean [-minneighbors=N] [-black|-white] [pbmfile]
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OPTION USAGE

14       You  can  use  the minimum unique abbreviation of the options.  You can
15       use two hyphens instead of one.  You can separate an option  name  from
16       its value with white space instead of an equals sign.
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DESCRIPTION

20       This program is part of Netpbm(1).
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22       pbmclean  cleans up a PBM image of random specks.  It reads a PBM image
23       as input and outputs a PBM that is the same as the  input  except  with
24       isolated  pixels  inverted.  An isolated pixel is one that has very few
25       neighboring pixels of the same color.  The -minneighbors  option  gives
26       the number of same-color neighbors are required.
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28       The default is 1 pixel -- only completely isolated pixels are flipped.
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30       (A  -minneighbors  value greater than 8 generates a completely inverted
31       image (but use pnminvert to do that) -- or a completely white  or  com‐
32       pletely black image with the -black or -white option).
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34       pbmclean  considers the area beyond the edges of the image to be white.
35       (This matters when you consider pixels right on the edge of the image).
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37       You can use pbmclean  to clean up 'snow' on bitmap images.
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OPTIONS

41       -black
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44       -white Flip pixels of the specified color.  By default, if you  specify
45              neither  -black  nor -white, pbmclean flips both black and white
46              pixels which do not have sufficient identical neighbors.  If you
47              specify  -black, pbmclean leaves the white pixels alone and just
48              erases isolated black pixels.  Vice versa for -white.   You  may
49              specify  both  -black  and -white to get the same as the default
50              behavior.
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53       -minneighbors=N
54              This determines how many pixels must be in a  cluster  in  order
55              for  pbmclean to consider them legitimate and not clean them out
56              of the image.  See Description ⟨#description⟩ .
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58              Before December 2001, pbmclean accepted -N instead of -minneigh‐
59              bors.  Before Netpbm 10.27 (March 2005), -minneighbors was -min‐
60              neighbor.
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SEE ALSO

67       pbm(1)
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AUTHOR

71       Copyright (C) 1990 by Angus Duggan Copyright (C) 1989 by Jef Poskanzer.
72       Copyright (C) 2001 by Michael Sternberg.
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74       Permission  to  use, copy, modify, and distribute this software and its
75       documentation for any purpose and without fee is hereby  granted,  pro‐
76       vided  that  the  above  copyright notice appear in all copies and that
77       both that copyright notice and this permission notice  appear  in  sup‐
78       porting  documentation.   This  software  is  provided  'as is' without
79       express or implied warranty.
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83netpbm documentation              27 Feb 2005          Pbmclean User Manual(0)