2D Articulatory velum modeling applied to copy synthesis of sentences containing nasal phonemes

Articulatory synthesis could become a valuable tool to investigate links between articulatory gestures and acoustic cues. This papers presents the construction of an articulatory model of the velum which is intended to complete a model already comprising other articulators. The velum contour was delineated and extracted from a thousand of X-ray images corresponding to short sentences of French. A principal component analysis was applied in order to derive the main deformation modes. The weight of images corresponding to an open velopharyngeal port was increased in the analysis so as to obtain linear components rendering the velum deformation modes. The first corresponds to the opening and comes with a shape modification linked to the apparition of a bulb in the upper part of the velum when it rises. The area function of the oral tract is modified so as to incorporate the velum movements. This model is connected with acoustic simulations in order to synthesize sentences containing nasal French vowels and consonants.