PBMTOPGM

NAME

      pbmtopgm - convert portable bitmap to portable graymap by averaging
      areas

SYNOPSIS

      pbmtopgm <width> <height> [pbmfile]

DESCRIPTION

      Reads a portable bitmap as input. Outputs a portable graymap created
      by averaging the number of pixels within a sample area of width by
      height around each point. Pbmtopgm is similar to a special case of
      ppmconvol. A ppmsmooth step may be needed after pbmtopgm.
      Pbmtopgm has the effect of anti-aliasing bitmaps which contain
      distinct line features.

SEE ALSO

      pbm(5)

AUTHOR

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

NOTES

      Pbmtopgm works best with odd sample width and heights.