Most image sensors are quite similar (ignoring weirdos like X-Trans and Foveon) so they could use the same format and decoding algorithm. It's a 16-bit integer (padded out from 12 or 14 bits) for each pixel with a Bayer color filter. Maybe throw in some parameters like a suggested gamma curve.

Foveon has awful Foss support so far. Older foveon models also require an older version of windows to run the antiquited software to process raw pics, it's maddening.