An Optimization of Fundamental Frequency and Length of Syllables for Rule-Based Speech Synthesis

In this paper an optimization method has been proposed to minimize the differences of fundamental frequency (F-0) and the differences of length among the speakers and the phonemes. Within tone languages use pitch variation to construct meaning of the words, we need to define the optimized fundamental F-0 and length to obtain the naturalness of synthetic sound. Large variability exists in the F-0 and the length uttered by deferent speakers and different syllables. Hence for speech synthesis normalization of F-0 and lengths are important to discriminate tones. Here, we implement tone rule by using two parameters; optimized F-0 and length. As an advantage in the proposed method, the optimized parameters can be separated to male and female group. The effectiveness of the proposed method is confirmed by the distribution of F-0 and length. Listening tests with high correct rates approve intelligibility of synthetic sound.