NAME

       pbmclean - flip isolated pixels in portable bitmap

SYNOPSIS

       pbmclean [-minneighbors=N] [-black|-white] [pbmfile]

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

       Before December 2001, pbmclean accepted -N instead of -minneighbors.

DESCRIPTION

       pbmclean cleans up a PBM image of random specs.  It reads a PBM image as input and outputs a PBM that  is
       the same as the input except with every pixel which has less than N identical neighbours inverted.

       The default for N is 1 - only completely isolated pixels are flipped.

       (A value of N greater than 8 generates a completely inverted image (but use pnminvert to do that) -- or a
       completely white or completely black image with the -black or -white option).

       pbmclean considers the area beyond the edges of the image to be white.  (This matters when  you  consider
       pixels right on the edge of the image).

       You can use pbmclean to clean up "snow" on bitmap images.

OPTIONS

       -black

       -white Flip  pixels  of  the  specified  color.   By  default,  if you specify neither -black nor -white,
              pbmclean flips both black and white pixels which do not have sufficient identical  neighbors.   If
              you  specify -black, pbmclean leaves the white pixels alone and just erases isolated black pixels.
              Vice versa for -white.  You may specify both -black and -white to get  the  same  as  the  default
              behavior.

SEE ALSO

       pbm(5)

AUTHOR

       Copyright  (C)  1990  by Angus Duggan Copyright (C) 1989 by Jef Poskanzer.  Copyright (C) 2001 by Michael
       Sternberg.

       Permission to use, copy, modify, and distribute this software and its documentation for any  purpose  and
       without  fee  is  hereby  granted, provided that the above copyright notice appear in all copies and that
       both that copyright notice and this permission notice appear in supporting documentation.  This  software
       is provided "as is" without express or implied warranty.

                                                   18 Oct 2001                                       pbmclean(1)