I am really happy from receiving these comments because that was my first impression.
How are you expecting to create encrypted signature within raw data using scripting language ?
Presumably, you'd put the actual encryption stuff in the C code...
Encrypted signature within raw data is feasible but is it usefull and, encountering first objective, secure ?
It depends on the objective. It's possible that the listing you posted doesn't describe the objective accurately and they are actually trying to do something more reasonable...
If the objective is an image authentication system similar to the ones I linked in my earlier post, it appears deeply misguided to think you could do this in software on the camera.
Some related objectives (like "This image was produced by someone in possession of a particular secret") should be achievable.
One would think they must read these forums, so maybe they will enlighten us
