DEVICE AND METHOD FOR CELP TYPE VOICE ENCODING AND DEVICE AND METHOD FOR CELP TYPE VOICE DECODING

摘要

PROBLEM TO BE SOLVED: To obtain a synthesized voice of higher quality by providing a pulse diffusion part, etc., which convolutes a diffusion pulse and a pulse vector, and selecting selecting a diffusion pattern by a diffusion pattern storage and selection part by using the voiced/voiceless decision result of a voice signal. SOLUTION: The pulse vector diffusion part 217 generates diffusion vectors by channels from diffusion patterns selected by the diffusion pattern storage and selection part 215 and pulse vectors generated by a pulse vector generation part 216 through convolution operation based upon a specific calculation expression. A diffusion vector addition part 218 adds the diffusion vectors obtained by the pulse vector diffusion part 217 to generate a sound source vector. Then a distortion calculation part 206 calculates a specific value using the noise code vector candidate obtained by the diffusion vector addition part 218. Further, the diffusion pattern storage and selection part 215 selects a diffusion pattern by using the voiced/voiceless decision result of a voice signal.