I'm looking to find or collect a corpus of color images in more-than-8-bits per color, in some reasonably straightforward file format(s), e.g., 30-bit color with 10 bits per channel, packed 10/10/10 into 32 bits with 2 bits left over for padding or alpha, or 12/12/8 RGB, or 16-bits/channel 48-bit RGB or 64-bit RGBA, or whatever.
My actual goal is to figure out how to detect and compress various in-memory representations of images, like some of the weird deep-color representations natively supported by some graphics cards (10 to 12 bits per channel or whatever, maybe with different numbers of bits per channel).
(For the moment, I'm not as interested in really weird, camera-specific "raw" representations of photographs that depend on bizarre details of raw nonuniform RGB pixel layouts (e.g., where half the subpixels are green) though in principle I want to be able to handle that stuff too, eventually.)
I'm rather more interested in intermediate representations that may be used by hi-res and HDR image processing programs (or such modes of Photoshop/Gimp/photo or cinema editing software/whatever), such as 48-bit pixels with 16-bit color channels, or asymmetric monstrosities directly supported by the strange new instructions some processors or GPUs have. (E.g., the ones with one shared exponent for 3 mantissas, on the assumption that they're all on the same general scale that matters, because hey, it's probably a pixel where the relevant logarithmic intensity range is the same.)
What I'm really trying to do is to make sure I can discriminate between and various likely in-memory representations of images that are likely to be common in the near future, if not now, in programs that process images, and to make sure my code can figure out basic stride and alignment issues---e.g., that pixels are 24 vs. 32 vs. 36 vs. 40 vs. 48 bits---and where the channels are. (E.g., whether 32 bits is 10/10/10/2 RGBA, or 12/12/8 RGB.)
Any pointers to relevant test images, file formats, and image conversion utilities would be appreciated. (Anything particularly useful will mostly end up in free software, assuming I get that far.)