Patent ID: 7469070

Claim:
A method for determining a context for coding, comprising the steps of: (A) evaluating a neighbor condition corresponding to a plurality of neighbor blocks to a current block in a bitstream of digital video, wherein (1) said neighbor condition comprises (i) a first of said neighbor blocks having an unavailable macroblock address, (ii) a second of said neighbor blocks having an intra-prediction mode of a plurality of prediction modes, (iii) a third of said neighbor blocks having a skip mode of said prediction modes and (iv) a reference index zero flag having a non-zero condition and (v) a prediction mode flag having a zero condition and (2) said prediction mode flag has said zero condition where (i) a fourth of said neighbor blocks is sub-partitioned and has a sub-macroblock prediction mode that is not an inter-prediction mode of said prediction modes and not a bi-directional prediction mode of said prediction modes and (ii) a fifth of said neighbor blocks is unpartitioned and has a macroblock partition prediction mode that is not said inter-prediction mode and not said bi-directional prediction mode; (B) generating a plurality of first variables based on said neighbor condition; (C) calculating a context index increment variable based on said first variables; and (D) coding said bitstream using a binary arithmetic coding based on a particular context among a plurality of context determined from said context index increment variable.