You're welcome to ask me for help in compiling these, but I don't promise to be of much help. I've only recently started to learn the tricks of compiling things on odd platforms.
Here at MIT, Seth Finkelstein compiled this package for AIX, Solaris, and Ultrix, and I compiled it for SunOS:
giftoppm foobar.gif > barquux.ppmwill do what you want, if you replace "foobar.gif" and "barquux.ppm" with the filenames you'd like to use.
ppmtogif -transparent #rgb barquux.ppm > fooquux.gif(where, again, "barquux.ppm" and "fooquux.gif" are replaced with the appropriate filenames, and "#rgb" is replaced with the name of the color which you are converting to a transparent color). Most frequently, #rgb will be a hexidecimal number like "#e95cef" (a shade of purple) or "#ffffff" (white) , though you could conceiveably use any of the acceptable color specifications which are listed in the ppmmake (1) manpage. I usually use white for the color which I am going to make transparent - it stands out in most pictures fairly well. Another color you might want to use is #bfbfbf, which is the default background color of Mosaic for X.
If some of these commands that contain a hash (or pound) symbol ("#") don't work, try preceding the "#" with a backslash ("\"). For example:
ppmtogif -transparent \#bfbfbf foobar.ppmThis is necessary because some unix shells (apparently sh and ksh, and perhaps others) interpret a "#" as the beginning of a comment.
giftoppm foobar.gif | ppmtogif -transparent #rgb > fooquux.gifIf you have any questions about this process, please feel free to contact me for help, although I make no claims as to my actual helpfulness. :-)
-Eric Mumpower (email@example.com)