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.