Patent ID: 8467451

Claim:
A method of selecting a number of candidate prediction modes for a block in a video sequence, the method comprising: calculating a cost value of each of prediction modes for each of a predetermined number of blocks, wherein the predetermined number of blocks is a subset of a total number of blocks and wherein the cost value is related to the computational complexity of each of the prediction modes; identifying one of the prediction modes having the smallest cost value for each of the predetermined number of blocks; calculating a function value of each of the prediction modes for each of the predetermined number of blocks using a cost function; ranking the prediction modes for each of the predetermined number of blocks by the function value of each of the prediction modes and identifying an ordinal value of the one prediction mode having the smallest cost value, the ordinal value being related to the ordinal number of the one prediction mode after the ranking; calculating a feature value of each of the predetermined number of blocks based on the function value of each of the prediction modes related to each of the predetermined number of blocks; identifying a plurality of sets of blocks, each set of blocks having substantially the same feature value; identifying the number of each set of blocks and calculating a sum of the ordinal value of the one prediction mode for each of the predetermined number of blocks in the each set of blocks; calculating an average value of the sum over the number of the each set of blocks for each set of the plurality sets of blocks; and determining a relation between the average values and the feature values for the predetermined number of blocks.