| 摘要 |
PURPOSE:To improve sound quality and to drastically decrease the quantity of computation by obtaining multipulses without using pitch prediction for the pulses which are not strongly correlated with each of pitches. CONSTITUTION:The sound source signal of the voice signal of a frame section is indicated by using the 1st multipulses obtd. by pitch prediction and the 2nd multipulses obtd. by without pitch prediction. Further, the frame is previously divided to the sub-frames corresponding to the pitch periods and the multipulses are obtd. by the pitch prediction only with the one section of the sub-frames in order to utilize the quasiperiodicity of every pitch of the multipulse sound source and to decrease the computation quantity. The signal is reproduced by the multipulses to remove the influence thereof; thereafter, the multipulses are obtd. without the p[itch prediction in said frame. Namely, a 1st pulse decoder 720 decodes the amplitude and position of the pitch predicted multipulses and a 2nd pulse decoder 725 decodes the amplitude and position of the 2nd multipulses. |
