Construction and evaluation of an articulatory model of the vocal tract

Articulatory models of the vocal tract play an important role in the investigation of relations between the geometry of the vocal tract and its acoustic properties. This paper presents the construction and the evaluation of an articulatory model from a corpus of X-ray and MRI images, which approximates lateral vocal tract shapes of vowels and consonants with a very good precision. First, this paper describes the coordinate system used to represent the tongue contour and the strategy employed to find the deformation modes. Then, a speaker adaptation procedure is presented and the adapted model is evaluated on a second database of X-ray images. This evaluation shows that the model approximates tongue shapes with a very good precision. Finally, a centerline algorithm, i.e. an algorithm used to decompose the vocal tract in a sequence of elementary tubes, is presented.