| 摘要 |
PURPOSE:To transmit a predictive residual by a low bit rate, and also, to obtain a synthetic voice having a high quality by converting the predictive residual to a zero crossing wave and transmitting it to a decoder side together with sound source strength information. CONSTITUTION:A pulse train being a predictive residual signal which is generat ed and reconstituted by a residual signal reconstituting device 7 is supplied to an 8-order PARCOR synthesizing filter 9, and with respect to this filter 9, as well, a PARCOR type lattice filter is used, and an 8-order decoded PARCOR coefficient Km from a coefficient decoder 8 is supplied to the filter 9. An input signal of the filter 9 corresponds roughly to a predictive residual from a PARCOR analytical filter 3 of an encoder side, and from this PARCOR synthesizing filter 9, a digital reproducing synthetic voice is obtained. This digital reproducing synthetic voice is returned to an analog sound signal by a D/A converter 10, and in an output terminal 11, a sound signal having a high quality being similar to an input voice is obtained. |
