Patent ID: 8891630

Claim:
A method of decoding a bitstream of encoded data to reconstruct a significance map for a transform unit, the method comprising: for each bit position in the significance map, determining a context for that bit position based upon a partition set, decoding the encoded data based on the determined context to reconstruct a bit value, and updating the context based on that reconstructed bit value, wherein the reconstructed bit values form the decoded significance map; wherein the transform unit is sized 4×4; wherein the partition set assigns contexts to bit positions in accordance with a block-based mapping given by: 0, 1, 2, 3, 4, 5, 2, 3, 6, 6, 7, 7, 8, 8, 7, and wherein the above integers represent the contexts assigned to the bit positions of a 4×4 block significance map.