| 摘要 |
PURPOSE:To facilitate the pulse search processing and the pulse number asignment processing of every sub-frame by converting a pitch period of a sound signal to a prescribed pitch period by a pitch period converter and executing an encoding processing. CONSTITUTION:An output of a pitch extractor 31 for inputting a sound signal Sv is quantized by a quantizer 32, sent out to a multiplexing device which is not shown in the figure, and also, reverse-quantized by a reverse quantizer 33, and inputted to a pitch period converter 34. The converter 34 converts a pitch period by which the sound signal Sv is varied, to a prescribed pitch period, based on an output of the reverse quantizer 33, and gives it to an adder 1 and a feature parameter analyzer 11. In such a way, the operation time required for a pulse search processing of a pulse searching device 18 and the memory capacity of a work area become roughly constant, a pulse number assignment of every sub-frame becomes fixable, and the control is simplified. |
