Fractal interpolation for the modification of pulse source signal in PARCOR synthesizer

It is considered that the buzz voice quality of synthesized speech, which is one of the major problems of the PARCOR synthesizer, is caused by rapid and large discontinuities of pulse train source signals. This paper focuses on the characteristics of the discontinuities in source signals which are derived from sustained vowels using PARCOR inverse filtering. Wavelet analysis indicates that the characteristics of the discontinuities in these source signals are different from those of pulse train. Based on this result, a new technique for the modification of the pulse train is proposed.