Block-based random access capable lossless graphics asset compression

A method includes determining a sequence for compressing blocks of pixels in an image; compressing the blocks sequentially according to the sequence, wherein a first component of a first block is compressed by: selecting a variable-length mode from supported compression modes to compress the first component of the first block based on: determining that the first block is different from previously-compressed blocks compressed according to the sequence; determining that pixels within the first component are different; and determining that a bit length needed for compressing the first component using the variable-length mode is less than a bit length needed for representing the first component uncompressed; and generating a first compression of the first component of the first block using a symbol width selected based on magnitudes of delta values used for encoding the pixels within the first component of the first block.