| 摘要 |
PURPOSE:To decrease a computation quantity and to allow the sufficient execution of correction of pulse resonance by executing an LPC analysis and pitch extraction, then calculating the autocorrelation of the impulse response of only the spectrum envelope filter and the cross correlation of the impulse response and input voice signal in a section where there are no pitches. CONSTITUTION:After the LPC analysis 2 and the pitch extraction 3 are executed, the autocorrelation of the impulse response of only the spectrum envelope filter is calculated by an autocorrelation calculator 9 in the section where there are no pitches and the cross correlation of the impulse response of only the spectrum envelope filter and the input voice signal is calculated in a cross correlation calculator 10. The operations of raising a pulse in the position where the cross correlation is max., subtracting the autocorrelation normalized at the pulse amplitude from the cross correlation in the position of the pulse, determining this correlation as the fresh cross correlation and further correcting the pulse amplitude are repeated. The computation quantity is decreased in this way and the correction of the pulse amplitude is sufficiently executed. |
