pbmtopgm(12 Dec 1990)                       pbmtopgm(12 Dec 1990)

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 soft-
       ware 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.

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