Provided by: netpbm_11.05.02-1.1build1_amd64 

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
netpbm documentation Ppmtogif User Manual(1)