September 22-25, 1997
In this paper we present a high-quality text-to-speech system using diphones. The system is based on a Harmonic plus Noise (HNM) representation of the speech signal. HNM is a pitch-synchronous analysis-synthesis system but does not require pitch marks to be determined as necessary in PSOLA-based methods. HNM assumes the speech signal to be composed of a periodic part and a stochastic part. As a result, different prosody and spectral envelope modification methods can be applied to each part, yielding more natural-sounding synthetic speech. The fully parametric representation of speech using HNM also provides a straightforward way of smoothing diphone boundaries. Informal listening tests, using natural prosody, have shown that the synthetic speech quality is close to the quality of the original sentences, without smoothing problems and without buzziness or other oddities observed with other speech representations used for TTS.
Bibliographic reference. Stylianou, Yannis / Dutoit, Thierry / Schroeter, Juergen (1997): "Diphone concatenation using a harmonic plus noise model of speech", In EUROSPEECH-1997, 613-616.