Not all bitmaps use RLE. If you use the 24-32 bit versions the pixel data is just after all of the header information. Note most of the time it is stored bottom-up. I agree bitmap is not good for games because it is uncompressed and even if it is compressed using RLE, RLE is not that great of a compression method compared to Huffman, LZW or LZ77 for instance.
Originally posted by Sayeh
As I recall, .BMP uses RLE. As others have said, it's not very effecient. It would be better to just save the raw pixmap data and the associated color table.
One Color table for your game, and then nothing but pixmap data. it's very compressible if you want to go that route.