pbmclean



Pbmclean User Manual(0)                                Pbmclean User Manual(0)




NAME

       pbmclean - flip isolated pixels in portable bitmap



SYNOPSIS

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



OPTION USAGE

       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.



DESCRIPTION

       This program is part of Netpbm(1).

       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
       isolated  pixels  inverted.  An isolated pixel is one that has very few
       neighboring pixels of the same color.  The -minneighbors  option  gives
       the number of same-color neighbors are required.

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

       (A -minneighbors value greater than 8 generates a  completely  inverted
       image  (but  use pnminvert to do that) -- or a completely white or com-
       pletely 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.


       -minneighbors=N
              This determines how many pixels must be in a  cluster  in  order
              for  pbmclean to consider them legitimate and not clean them out
              of the image.  See Description .

              Before December 2001, pbmclean accepted -N instead of -minneigh-
              bors.  Before Netpbm 10.27 (March 2005), -minneighbors was -min-
              neighbor.






SEE ALSO

       pbm(1)



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,  pro-
       vided  that  the  above  copyright notice appear in all copies and that
       both that copyright notice and this permission notice  appear  in  sup-
       porting  documentation.   This  software  is  provided  ’as is’ without
       express or implied warranty.



netpbm documentation              27 Feb 2005          Pbmclean User Manual(0)

Man(1) output converted with man2html