Recording script design for corpus-based TTS system based on coverage of various phonetic elements

This paper describes a new recording script generation method that can create speech databases for corpus-based TTS (text to speech) systems. This method is efficient due to its two features: (1) it has a 2-stage algorithm to generate the recording script with consideration of the balance of triphone, syllable and morpheme elements; (2) it can control types of phonetic elements included in the recording script via the weight coefficients of the phonetic elements. An evaluation shows that the 2-stage algorithm is effective in raising the coverage of phonetic elements and that this method yields a recording script containing various phonetic elements. A preference test shows that changing the selection criteria influences the quality of the synthesized speech. The same test also shows that it is better to take account of morpheme-based elements than syllable-based elements in generating a task-specific recording script.