fstopgm(1)                                             fstopgm(1)

       fstopgm  -  convert  a  Usenix  FaceSaver(tm)  file into a
       portable graymap

       fstopgm [fsfile]

       Reads a Usenix FaceSaver(tm) file as  input.   Produces  a
       portable graymap as output.

       FaceSaver(tm)  files  sometimes  have  rectangular pixels.
       While fstopgm won't re-scale them into square  pixels  for
       you,  it  will  give you the precise pnmscale command that
       will do the job.  Because of this, reading a FaceSaver(tm)
       image is a two-step process.  First you do:
         fstopgm > /dev/null
       This will tell you whether you need to use pnmscale.  Then
       use one of the following pipelines:
         fstopgm | pgmnorm
         fstopgm | pnmscale -whatever | pgmnorm
       To go to PBM, you want something more like one of these:
         fstopgm | pnmenlarge 3 | pgmnorm | pgmtopbm
         fstopgm | pnmenlarge 3 | pnmscale <whatever> | pgmnorm | pgmtopbm
       You want to enlarge when going to a bitmap because  other-
       wise  you  lose  information; but enlarging by more than 3
       does not look good.

       FaceSaver is a registered trademark of Metron Computerware
       Ltd. of Oakland, CA.

       pgmtofs(1),   pgm(5),   pgmnorm(1),   pnmenlarge(1),  pnm-
       scale(1), pgmtopbm(1)

       Copyright (C) 1989 by Jef Poskanzer.

                           06 April 89                          1