I have a bunch of values that seem to be 12-bit numbers. If I put them in a matrix and scale each one to a value 0-255 and then show them as an image, I get something that looks like a photo, but it's quite bland.
I think that they might be direct reading off of a camera sensor. They have a sort of stippled pattern, kind of like plaid, that makes me think that they might be a sort of Bayer filter. https://en.wikipedia.org/wiki/Bayer_filter
I want to convert these number into RGB values. What do I need to do? For each 2x2 in the Bayer pattern, do I convert the red to R, blue to B, and then average the green values? Do I need a gamma correction?
I noticed that the max value is much lower than the full 0xfff. Do I need to scale the values?
The procedure is well-described here: https://www.strollswithmydog.com/raw-file-conversion-steps/
Looks like I was getting it mostly right by the problem was grey balance. There is a transformation that needs to be made on the sensor values to map it to the 0-255 RGB component and the transform that needs to be made depends on the color. The best way is to take a photo of a perfect grey and calibrate.