  This paper focuses on the analysis and synthesis of hypo and hyperarticulated
speech in the framework of HMM-based speech synthesis. First of all, a new
French database matching our needs was created, which contains three identical
sets, pronounced with three different degrees of articulation: neutral, hypo
and hyperarticulated speech. On that basis, acoustic and phonetic analyses were
performed. It is shown that the degrees of articulation significantly
influence, on one hand, both vocal tract and glottal characteristics, and on
the other hand, speech rate, phone durations, phone variations and the presence
of glottal stops. Finally, neutral, hypo and hyperarticulated speech are
synthesized using HMM-based speech synthesis and both objective and subjective
tests aiming at assessing the generated speech quality are performed. These
tests show that synthesized hypoarticulated speech seems to be less naturally
rendered than neutral and hyperarticulated speech.
