SPEECH COMPRESSION AND DECOMPRESSION APPARATUS HAVING SCALABLE BANDWIDTH STRUCTURE AND ITS METHOD

摘要

PROBLEM TO BE SOLVED: To provide a speech compression and decompression apparatus having a scalable bandwidth structure and a method thereof. SOLUTION: A band transform unit 102 transforms a wideband speech signal to a narrowband low-band speech signal. A narrowband speech compressor 106 compresses the narrowband low-band signal and outputs the compression result as a low-band speech packet. Decompression units 108 and 110 decompress the low-band speech packet to obtain a decompressed wideband low-band speech signal. An error detection unit 114 detects an error signal that corresponds to a difference between the wideband speech signal and the decompressed wideband low-band speech signal. A high-band speech compression unit 116 compresses the error signal and the high-band speech signal of the wideband speech signal and outputs the compression result as a high-band speech packet. COPYRIGHT: (C)2005,JPO&NCIPI