Disabling jpeg should be fairly easy... we ought to be able to just jump past it after writing the raw. If you are lucky, you can just jump to the end of one of those functions that we've hooked, but there might be some essential housekeeping that has to happen after you take an image. Try it and see...
I'd gladly try, but I think I need some kind of jump start...
I don't have IDA and I'd rather work on Linux, and right now I really just have no clue how the firmware is structured.
It would be nice if someone already into this things would spend some time improving the wiki's
developers' documentation... I'm sure it's time well spent: people, like me, often just don't do things because they 1) see that few other people are doing them, so assume they're beyond themselves 2) don't quite know where to start.
Just see the topic about
temperature sensors: the functions to use those have been there since forever, I think, for some models. And only those models. Now that someone suggested that they may be there in all cameras, everyone is jumping at IDA and actually finding them.
I don't think I personally need a step-by-step tutorial, as in "press this and then that", but I'd benefit from a technical explanation of how the firmware is layed out (and there is
something like that, it's not bad but very limited), the difference between adding our own routines and modifying existing Canon routines (how do we actually do that, since we aren't modifying the firmware?), what I can expect to find in plain text in the firmware code, and what I should plan to reverse-engineer manually; and generally speaking, what sort of things I can expect to be able to change, and which others are set in stone (because they're not done in the ARM processor, or whatever reason).
Now I'll go back in a corner and stop hijacking this thread, but I thought I'd just throw a rock and see where it lands.