A flexible front-end for HTS
Matthew P. Aylett, Rasmus Dall, Arnab Kumar Ghoshal, Gustav Eje Henter, Thomas Wayne Merritt · 2014
Parametric speech synthesis techniques depend on full context acoustic models generated by language front-ends, which anal-yse linguistic and phonetic structure. HTS, the leading paramet-ric synthesis system, can use a number of different front-ends to generate full context models for synthesis and training. In this paper we explore the use of a new text processing front-end that has been added to the speech recognition toolkit Kaldi as part of an ongoing project to produce a new parametric speech synthesis system, Idlak. The use of XML specification files, a modular design, and modern coding and testing approaches, make the Idlak front-end ideal for adding, altering and experi-menting with the contexts used in full context acoustic models. The Idlak front-end was evaluated against the standard Festival front-end in the HTS system. Results from the Idlak front-end compare well with the more mature Festival front-end (Idlak-2.83 MOS vs Festival- 2.85 MOS), although a slight reduction in naturalness perceived by non-native English speakers can be attributed to Festival’s insertion of non-punctuated pauses. Index Terms: speech synthesis, text processing, parametric synthesis, Kaldi, Idlak