This article explains the mechanism of finding signatures automatically with the "Signature finder" (finsig/gensig). The original text was posted on 31-08-2008 by fudgey in the CHDK forum: Hi... documentation I could find about the signature finder in the tools directory was sort of scarce, so I wrote this while fiddling with it a bit. I had my mind set on adding new features, not porting new cameras