Abstract ;An automatic approach to lip localization, contour extraction and tracking is presented, which combines CbCr color space, Fisher transform and deformable templates. Firstly, a skincolor model is constructed for skin detection in CbCr color space so that the approximate lip region can be obtained based on the geometry features of human face. Then, the color difference between lip and skin is enhanced by Fisher transform. Preprocessing of brightness is carried out before segmentation, and the threshold is obtained by Otsu method. Next, the lip color model is used to validate the segmentation result of accurate localization and the deformable templates are used for lip contour extraction. Based on the segmentation result, a method of curves fitting for edges of inner mouth is presented to extract the inner contour robustly. Finally, locating result of previous frame is predicted as the next lip region, in which lip localization and contour extraction are executed for lip tracking.
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2007, Vol. 20 
