US Patent 9984475 Compression using index bits in MSAA

A palette compressed representation may be stored in the index bits, when that is possible. The savings are considerable in some embodiments. In uncompressed mode, the data uses 2304 (2048+256) bits, and in compressed mode, the data uses 1280 bits. However, with this technique, the data only uses the index bits, (e.g. 256 bits) with a 5:1 compression improvement over the already compressed representation, and with respect to the uncompressed representation it is a 9:1 compression ratio.