Control of Prosodic Features for Keyword Emphasis in a Text-to-Speech Synthesizer

Abstract

For the purpose of designing a method to control the main speech parameters for keyword emphasis in a text-to-speech synthesizer, the relation between speech parameters and emphasis level is determined from experiments. Twelve subjects are instructed to modify keyword emphasis to achieve natural sounding speech from three sentences. An interactive speech editor with a graphical user interface is developed for the experiments. The editor allows the subjects to control speech intensity, speech rate and average fundamental frequency of the keyword, and of the other sentence components. Furthermore, subjects can also control pause (silence) duration preceding and following the keyword. Extracted relations between prosodic feature parameters and emphasis level shows that speech intensity and speech rate are independent of sentence content. Speech intensity increases linearly and speech rate decreases linearly with emphasis level. On the other hand, average fundamental frequency and pause duration depend on sentence content, and relatively large changes are required to strongly emphasize keywords using pause insertion and increased fundamental frequency.

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References

Fujisaki

Kawai

(1988). Realization of linguistic information in the voice fundamental frequency contour of the spoken Japanese. In Proceedings of IEEE International Conference on Acoustics, Speech and Signal Processing (pp.663–666). New York: IEEE

Hakoda

Nakajima

Hirokawa

Mizuno

(1990). A new Japanese text-to-speech synthesizer based on COC synthesis method. In Proceedings of International Conference on Spoken Language Processing (pp.809–812). Kobe, Japan: The Acoustical Society of Japan

Halstead-Nussloch

(1989). The design of phone-based interfaces for consumers. In Proceedings of the CHI'89 Conference on Human Factors in Computing System (pp.347–352). New York: ACM

Hamada

Chiba

(1991) A study on keyword emphasis method for voice message output. In Proceedings of the Seventh Symposium on Human Interface (pp. 129–132). Kyoto, Japan: The Society of Instrument and Control Engineers

Hirschberg

Pierrehumbert

(1986). The intonational structuring of discourse. In Proceedings of the 24th Annual Meeting of the Association for Computational Linguistics (pp. 136–144). Association for Computational Linguistics, Morristown, New Jersey

Nakajima

Hamada

(1988). Automatic generation of synthesis units based on context oriented clustering. In Proceedings of IEEE International Conference on Acoustics, Speech and Signal Processing (pp.659–662). New York: IEEE

Shirai

Iwata

Ohno

(1986). Pitch contour control in Japanese conversational speech. In Proceedings of IEEE International Conference on Acoustics, Speech and Signal Processing (pp.2043–2046).: IEEE

Takeda

Ichikawa

(1990). Analysis of prosodic features of prominence in spoken Japanese sentences. In Proceedings of 1990 International Conference on Spoken Language Processing (pp.493–496). Kobe, Japan: Acoustical Society of Japan