Hi.
Few days ago I released a tonemapper for LDR images and I discussed about it, here:
http://chdk.setepontos.com/index.php/topic,3006.0.htmlSomebody gave me the idea to put it into CHDK, to get tonemapping directly from the camera. So I started to think seriously about it and I would like to ask developers if this is feasible.
The tonemapping works in two steps:
A) desaturate and blur the image
B) combine each channel and the image blurred with a function
Here is what I think why it
might be possible in chdk
1) Every step can be implemented in fixed point
2) It's not necessary to do a gaussian blur; a IIR blur it's enough
3) The blurred image can be scaled down, to keep low memory usage
4) The function can be computed very fast with a lookup table
In my program, I implemented the tonemapping for 8-bit images, but I think that it can be implemented for 12(10?) or 16 bit images (guess in the camera's step just before 8 bit quantization and converting to jpeg).
I don't know CHDK internals, how fast is the camera's processor, or if it's possible to access (RGB?) data before writting to JPEG (or even better, before quantization to 8 bit). I would like to hear an opinion of a CHDK developer.
Paul
