MPEG-1 audio layer III decoding device achieving fast processing by eliminating an arithmetic operation providing a previously known operation result

摘要

An MPEG-1 audio layer III decoding device, which can perform fast decoding of MP3 by performing fast inverse quantization of Huffman code data, includes a bit stream decomposing portion for decomposing an input bit stream of MP3 into side information including bit allocation information and Huffman table information, a scale factor and Huffman code data; a scale factor decoder for decoding the scale factor decomposed from the bit-stream based on the side information; a Huffman decoder for decoding the Huffman code data decomposed from the bit-stream based on the Huffman table information included in the side information; a zero detecting portion for detecting a band of the Huffman code data all providing values of zero; an inverse quantizer for performing inverse quantizing processing on the Huffman code data based on the output of the zero detecting portion, the side information, the scale factor and the Huffman code data; and a hybrid filter bank portion for inversely mapping and decoding the output of the inverse quantizer into a time region signal.