| 摘要 |
PROBLEM TO BE SOLVED: To reproduce a voice reducing the deterioration of quality due to a transmission error at the time of applying a voice coding/decoding method by limiting the polarity of periodic pulses. SOLUTION: A time series vector outputted from a periodic pulse generation means 101 is weighted in accordance with gain applied from a pulse polarity limit means 105 and supplied to a synthetic file 103. The means 105 limits the polarity of a periodic pulse in the time series vector weighted in order to generate a synthetic voice by outputting the value of gain inputted from an optimum gain calculation means 102 when the sign of the gain is positive or outputting zero when the sign is negative. After executing the processing mentioned above for all time series vectors generated by the means 101, a time series vector minimizing a distance between an input voice and a synthetic voice is searched and the leading pulse position of the pulse string is outputted as a pitch position S6. |
