pic a.pic | troff | grops > a.ps
或
groff -p -Tps a.pic > b.ps

C:\Pr\gs\gs8.14\bin>gswin32c -dBATCH -dNOPAUSE -r150 -dTextAlphaBits=4 -dGraphicsAlphaBits=4 -sDEVICE=jpeg -sOutputFile=C:\a.jpg c:\a.ps

http://www.cs.wisc.edu/~ghost/doc/
http://www.cs.wisc.edu/~ghost/doc/AFPL/8.50/Use.htm
http://www.cs.wisc.edu/~ghost/doc/AFPL/8.50/Devices.htm

從 troff 處看到 A System for Algorithm Animation (Tutorial and User Manual)
google 看 "algorithm animation"

google: kernighan pic gif
http://perl.plover.com/obfuscated/ 提到 pnmcrop (也可參考其中的 Makefile)
找 ps2gif (in newsgroups)
找 netpbm