Cameratopam is derived from Dave Coffin's Dcraw program. Bryan Henderson derived it in April 2005. Bryan mainly just split it up into manageable pieces and replaced the parts that generate Netpbm formats and the command line parser. Dcraw and therefore Cameratopam is Copyright 1997-2005 by Dave Coffin, dcoffin a cybercom o net, and Dave licenses it to the public freely, except that the Foveon code (in foveon.c in Netpbm) is copyrighted by someone else (I don't know who). Dave licenses his copyright to the public freely, with the words, "Any code not declared GPL is free for all uses." Only the code in foveon.c in Netpbm was declared GPL in Dave's work. The foveon code is licensed to the public by its unknown copyright owner under GPL. The Netpbm maintainer distributes the entire Cameratopam package under GPL. Dave's distribution to Bryan may be a copyright violation, but strangely enough, Bryan's distribution to others is not. I.e. you DO have license from every copyright owner to do GPL-compatible things with this code. The problem with Dave's distribution is that he combined the Foveon code and his code into a single work and distributed it with GPL terms applying only to the Foveon code. The combined work may be a derivative work of the Foveon code and therefore cannot be distributed with the permission of the Foveon copyright owner, who gives that permission only on the condition that the distributor license the entire derivative work under GPL. Dave did not do that. He did not, for example, prohibit Bryan from distributing Dave's part of the code in object code only format.