NAME

       ppmtogif - replaced by pamtogif

DESCRIPTION

       This program is part of Netpbm(1).

       ppmtogif was replaced in Netpbm 10.37 (December 2006) by pamtogif(1).

       pamtogif is mostly backward compatible with ppmtogif.

       One  way  pamtogif  is  not  backward  compatible  with  ppmtogif  is  that  to  specify a
       transparency (alpha) mask with ppmtogif, you supply the transparency as a separate pseudo-
       PGM image and use the -alpha option, whereas with pamtogif, you supply an input image that
       has the transparency integrated into it, and there is no -alpha option.

       ppmtogif still exists as a separate  program  for  backward  compatibility,  but  it  runs
       pamtogif to do the essential work.  The compatibility ppmtogif interprets an -alpha option
       by reading the transparency image and combining it with  the  input  image,  then  feeding
       pamtogif  the combined image it expects.  Other than that, the compatibility ppmtogif just
       passes input and options directly to pamtogif.

       You should not make any new use of ppmtogif and if you modify an existing use, you  should
       upgrade to pamtogif.  But note that if you write a program that might have to be used with
       old Netpbm, ppmtogif is the only way to do that.

       Unless you use the -alpha option, you can simply change the name of the program.   If  you
       use -alpha, here is how to upgrade:

         $ ppmtogif -alpha=myalpha.pgm myinput.ppm >myoutput.gif

       becomes

         $ pamstack -tupletype=RGB_ALPHA myinput.ppm myalpha.pgm |  \
             pamtogif >myoutput.gif

Original Ppmtogif

       If  you  are  using Netpbm before 10.37, pamtogif doesn't exist, so you use ppmtogif.  You
       can use the pamtogif manual for ppmtogif, with the following exceptions.

       The current documentation of pamtogif documents all versions of  that  program.   Use  the
       information for Version 10.37 only.

       ppmtogif before Netpbm 10.31 does not accept PAM input at all.

       ppmtogif does not accept PAM input with transparency information in it.  Instead, ppmtogif
       has an -alpha option.

       The syntax of the option is -alpha=pgmfile.  ppmtogif treats the contents of the named PGM
       file  the  same  as pamtogif treats the alpha plane of a PAM.  The PGM image must have the
       same dimensions as the input file.  But unlike the PAM case, the alpha image need not have
       the  same  maxval as the input.  ppmtogif interprets the alpha file using the alpha file's
       maxval.

       You cannot specify both -transparent and -alpha.

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/ppmtogif.html