Variable-rate texture compression using fixed-rate codes

Abstract

A fixed rate compressor is used to perform variable rate texture compression. A texture image is accessed. A block size used to compress the image is automatically varied over the image to achieve variable rate texture compression. The block size may be selected to reduce the compressed texture image size and adapted in local regions of the texture image based on quality considerations, such as a quality condition that an error for each block be less that a threshold error. The restriction on block size and block types may be selected to perform decompression with hardware conventionally used to perform decompression of fixed-rate blocks. The quality condition may be user-selectable by a user input to provide additional control over the tradeoffs between quality and compression.