RAW is an image format introduced with the Dark Forces Remaster. It is the format for high resolution textures. RAW textures are true colour; they do not reference the original palettes.
RAW textures will be loaded in place of a classic texture if they have the same name (eg. hello.BM, hello.RAW). They must be exactly double the dimensions of the BM they are replacing. For example, a 64x128 BM must be replaced by a 128x256 RAW.
File format
RAW files are headerless and uncompressed. Image width and height are obtained from the corresponding BM.
A RAW contains nothing more than an array of pixels. The number of pixels will be BM width x BM height x 4.
Each pixel is a 4 byte struct:
Pixel {
Red
Blue
Green
Alpha
}