Predicting the effects of labial coarticulation is an important aspect with a view to developing an artificial talking head. This paper describes a concatenation approach that uses sigmoids to represent the evolution of labial parameters. Labial parameters considered are lip aperture, protrusion, stretching and jaw aperture. A first formal algorithm determines the relevant transitions, i.e. those corresponding to phonemes imposing constraints on one of the labial parameters. Then relevant transitions are either retrieved or interpolated from a set of reference sigmoids which have been trained on a speaker specific corpus. This labial corpus is made up of isolated vowels, CV, VCV, VCCV and 100 sentences. A final stage consists in improving the overall syntagmatic consistency of the concatenation.
Bibliographic reference. Robert, Vincent / Laprie, Yves / Bonneau, Anne (2007): "A phonetic concatenative approach of labial coarticulation", In INTERSPEECH-2007, 1402-1405.