Patent ID: 7630902

Claim:
A method for decoding a digital audio signal, comprising the steps of: receiving an encoded audio data stream that includes: entropy-encoded quantization indexes for an audio signal, indexes for assigned entropy codebooks that were used to encode the entropy-encoded quantization indexes, and codebook application ranges identifying segments of the entropy-encoded quantization indexes that were encoded by the respective entropy codebooks, wherein the codebook application ranges have been selected based on local properties of the quantization indexes, so that the codebook application ranges are independent of block quantization boundaries, meaning that at least one boundary between the codebook application ranges for different entropy codebooks is different than any of the block quantization boundaries; unpacking the data stream; decoding the entropy-encoded quantization indexes using the entropy codebooks within the respective identified codebook application ranges, thereby obtaining decoded quantization indexes; reconstructing subband samples that represent the audio signal in a frequency domain from the decoded quantization indexes; and processing the reconstructed subband samples using a synthesis filter bank, thereby transforming the reconstructed subband samples into audio pulse code modulation (PCM) samples of the audio signal.