We have introduced a novel Myanmar text to speech (MyanmarTTS) system with rule-based tone synthesis. Myanmar is a tonal language that possesses unique characteristics compared with other tonal languages such as Chinese, Vietnamese and Thai. Such languages have complicated fundamental-frequency (
F0) patterns of tones, and
F0 is of foremost importance. Myanmar tones are unique in their simplistic pattern related not only to
F0 but also, more specifically to duration. Myanmar tones have different durations between short-tone and long-tone groups. In accordance, we defined a tone rule employing two parameters
F0 at the center of the syllable and the syllable’s duration. The rule is implemented with a linear
F0 pattern. Large variability exists in the
F0 and duration uttered by different speakers of different syllables. Hence, for tone synthesis, normalization of the
F0 and duration is important and necessary to discriminate tones. We proposed a normalization method and the effectiveness of this method was confirmed in the distribution of the
F0 and duration. The intelligibility of the synthesized tone was confirmed through listening tests with correct rates of 95.6% for male and 97.8% for female speech. As a result, we showed that the linear pattern is sufficient for Myanmar tone synthesis.
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