VOICE ENCODER, VOICE DECODER, AND VOICE ENCODING AND DECODING METHOD

摘要

In speech coder 100, speech analysis section 101 extracts a fundamental frequency and spectrum envelope information from an input speech signal. Fundamental frequency quantization section 102 quantizes the fundamental frequency. Matrix generation section 103 generates a spectrum envelope curved surface from the spectrum envelope information and spectrum envelope quantization section 104 quantizes the spectrum envelope curved surface. Multiplexing section 105 multiplexes a quantized value of the spectrum envelope curved surface and a quantized value of the fundamental frequency and sends out the multiplexed quantized value. In speech decoder 200, spectrum envelope configuration section 202 reconfigures the spectrum envelope curved surface quantized from the spectrum envelope information and speech synthesis section 203 extracts the spectrum envelope curved surface based on the fundamental frequency information and synthesizes a decoded speech. This makes it possible to implement speech decoding of high quality even when information is transmitted at a low bit rate. <IMAGE>