Manual: pgmtopbm

Pgmtopbm User Manual(1)				   General Commands Manual			     Pgmtopbm User Manual(1)

NAME
       pgmtopbm - convert a PGM image to PBM

SYNOPSIS
       pgmtopbm

       [-floyd | -fs | -threshold | -hilbert | -dither8 | -d8 | -cluster3 | -c3 | -cluster4 | -c4 | -cluster8 | -c8]

       [-value val]

       [-clump size]

       [-randomseed integer]

       [pgmfile]

DESCRIPTION
       This program is part of Netpbm(1).

       This  program is almost entirely obsolete since Netpbm 10.23 (July 2004).  Use pamditherbw(1) to do what this program
       used to do.

       pgmtopbm never was the simple converter it appeared to be.  It was a dithering program.	Unfortunately, it didn't  do
       the dithering properly because it treated the PGM input samples as if they were directly proportional to light inten‐
       sity, but they are actually gamma-adjusted.

       pamditherbw is backward compatible with pgmtopbm except that it

       •      does the correct gamma adjustments.

       •      produces	PAM output instead of PBM.  (Modern Netpbm programs that accept PBM input also accept PAM input, but
	      if you need actual PBM, you can use pamtopnm with pamditherbw).

	      So use the manual for pamditherbw for pgmtopbm, except ignore anything that says it was added after Netpbm Re‐
	      lease 10.23 and ignore any options that are not shown in the synopsis above.

       Although pgmtopbm is mostly obsolete, the simple threshold method (specified by -threshold) is an exception.   Unlike
       the  other conversion methods, gamma-adjustment is not an issue with simple thresholding and pgmtopbm can produce PBM
       output directly.	 Note that even in this basic mode of operation pgmtopbm may produce output which is  slightly	dif‐
       ferent from what pamditherbw does because of differences in internal calculation.

       If you just want to convert a PGM image with maxval 1 to PBM, use pamtopnm(1).

SEE ALSO
       pamditherbw(1), pamtopnm(1), pbmtopgm(1), pamthreshold(1), pbmreduce(1), pgm(1), pbm(1)

AUTHOR
       Copyright (C) 1989 by Jef Poskanzer.

DOCUMENT SOURCE
       This manual page was generated by the Netpbm tool 'makeman' from HTML source.  The master documentation is at

	      http://netpbm.sourceforge.net/doc/pgmtopbm.html

netpbm documentation					17 July 2020				     Pgmtopbm User Manual(1)