Optimization of lip contour estimation

Developing algorithms based on lip contour estimation is a distinctive trend in lip segmentation which is the first step of visual speech recognition. In order to establish an optimized estimation of lip contour that is complex enough to describe the principal features of the lip but at the same time simple enough to be implemented, the selection of lip model, estimator as well as parameters for features of lips, including the horizontal length of snake of feature points and horizontal distance between these feature points will be optimized. Experimental result demonstrates that the optimized estimation method of lip contour provides more accurate and more stable results of lip segmentation.