Patent ID: 8108219

Claim:
A method of processing an audio signal, comprising: subdividing at least one channel in a frame of the audio signal into a plurality of blocks, at least two of the blocks being capable of different lengths; generating information indicating the subdivision of the channel into the blocks; generating indicator information indicating whether determining of an optimum prediction order for each block is allowed; determining an optimum prediction order as a final prediction order for each block if the indicator information indicates that determining of the optimum prediction order for each block is allowed, the optimum prediction order being determined based on a maximum permitted prediction order and a length of the block; determining the maximum permitted prediction order as the final prediction order if the indicator information indicates that determining of the optimum prediction order for each block is not allowed, the maximum permitted prediction order being applied to all of the plurality of blocks; predicting current data samples in the channel based on previous data samples, a number of the previous data samples used in the predicting step being the final prediction order; and obtaining a residual of the current data samples based on the predicted data samples, wherein the predicting step progressively increases a prediction order to the optimum prediction order as previous data samples become available, wherein the determining an optimum prediction order step includes, determining a global prediction order based on the maximum permitted prediction order; determining a local prediction order based on the length of the block; and selecting a minimum one of the global prediction order and the local prediction order as the optimum prediction order.