fstopgm Man page

fstopgm General Commands Manual fstopgm


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, read‐
ing 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 | pgmnorm | pgmtopbm
You want to enlarge when going to a bitmap because otherwise you lose
information; but enlarging by more than 3 does not look good.

FaceSaver is a registered trademark of Metron Computerware Ltd. of Oak‐
land, CA.


pgmtofs, pgm(5), pgmnorm, pnmenlarge, pnmscale, pgmtopbm


Copyright (C) 1989 by Jef Poskanzer.

06 April 89 fstopgm