> Prompted by a couple of "use ImageMagick" responses I've fiddled about > some more and come up with 'convert a b -compose difference -composite' > which seems to do the trick. > > Was this what you were thinking?
Yes, I knew there was some composite function in IM which calculates differences, but didn't remember in which command, not having used it myself, or I would have given more detail. Didn't know there was more than one way ;) Volker -- Volker Kuhlmann is list0570 with the domain in header http://volker.dnsalias.net/ Please do not CC list postings to me.
