Towards an unrestricted domain TTS system for African tone languages

  • Moses E. EkpenyongEmail author
  • Eno-Abasi Urua
  • Dafydd Gibbon


In this paper we discuss the procedural problems, issues and challenges involved in developing a generic speech synthesizer for African tone languages. We base our development methodology on the “MultiSyn” unit-selection approach, supported by Festival Text-To-Speech (TTS) Toolkit for Ibibio, a Lower Cross subgroup of the (New) Benue-Congo language family widely spoken in the southeastern region of Nigeria. We present in a chronological order, the several levels of infrastructural and linguistic problems as well as challenges identified in the Local Language Speech Technology Initiative (LLSTI) during the development process (from the corpus preparation and refinement stage to the integration and synthesis stage). We provide solutions to most of these challenges and point to possible outlook for further refinement. The evaluation of the initial prototype shows that the synthesis system will be useful to non-literate communities and a wide spectrum of applications.


TTS HLT Multi-unit selection Concatenative synthesis Terraced tone modeling 


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Moses E. Ekpenyong
    • 1
    Email author
  • Eno-Abasi Urua
    • 1
  • Dafydd Gibbon
    • 2
  1. 1.University of UyoUyoNigeria
  2. 2.Universität BielefeldBielefeldGermany

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