A statistical approach to lexical stress assignment for TTS synthesis

  • Catalin Ungurean
  • Dragos BurileanuEmail author
  • Aurelian Dervis


Lexical stress is primarily important to generate a correct pronunciation of words in many languages; hence its correct placement is a major task in prosody prediction and generation for high-quality TTS (text-to-speech) synthesis systems. This paper proposes a statistical approach to lexical stress assignment for TTS synthesis in Romanian. The method is essentially based on n-gram language models at character level, and uses a modified Katz backoff smoothing technique to solve the problem of data sparseness during training. Monosyllabic words are considered as not carrying stress, and are separated by an automatic syllabification algorithm. A maximum accuracy of 99.11% was obtained on a test corpus of about 47,000 words.

Text-to-speech synthesis Prosody prediction Lexical stress assignment n-grams Smoothing technique 


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Catalin Ungurean
    • 1
  • Dragos Burileanu
    • 1
    • 2
    Email author
  • Aurelian Dervis
    • 1
  1. 1.Speech Technology and Human-Computer Dialogue Laboratory, Faculty of Electronics, Telecommunications and Information Technology“Politehnica” University of BucharestBucharestRomania
  2. 2.Romanian Academy Center for Artificial IntelligenceBucharestRomania

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