Tongue shape synthesis based on Active Shape Model

Nowadays magnetic resonance imaging (MRI) technique has been widely used in speech production research since it acquires high spatial resolution data of vocal tract shape without any known harm of radiation. However, it would be time consuming and expensive to establish an overall articulatory database using MRI technique due to its low temporal resolution and the large expense of the MRI equipment. In this study, we propose a method to interpolate tongue shapes between static vowels to acquire dynamic tongue shapes. Firstly, a set of parameters is extracted to control tongue shape based on Active Shape Model (ASM). Then, control parameters are interpolated to synthesize dynamic tongue shapes from static vowels' articulation. To evaluate the method, a set of key points were chosen from both the MRI images and the synthesize tongue shapes. Results suggested that the dynamic properties of these key points from the synthesized tongue shapes resemble those of the actual dynamic tongue shapes.