| 摘要 |
PROBLEM TO BE SOLVED: To provide a system for encoding and decoding a sound signal for maintaining reproduced sound quality by reducing a LPC (linear predective coding) coefficient which requires the largest amount of information. SOLUTION: The system has an encoding part which generates a coded signal, on the basis of the multi-stage vector quantization signal of the LPC coefficient obtained from the first subframe of an input signal, the differential quantization signal of the LPC coefficient which is obtained by quantizing the difference between the multi-stage vector quantization signal of the LPC coefficient and the LPC coefficient obtained from a subframe succeeding the first subframe; a parameter quantization signal, based on parameters other than the LPC coefficient in the first subframe and the succeeding subframe; and the multi-stage vector quantization signal of the LPC coefficient; the differential quantization signal of the LPC coefficient; the parameter quantization signal, and a decoding part which obtains the reproducing sound signal, on the basis of an LPC coefficient separated from a received coded signal and decoded; parameters other than the LPC coefficient; a source sound signal generated from the parameters other than the LPC coefficient; and the LPC coefficient and the source sound signal. |
