Mouth localization is used in many applications such as face detection and lips reading. Visual information from lip movements helps to improve the accuracy and robustness of a speech recognition system. This paper presents a new method for automatic lip detection using geometric projection method and adaptive thresholding. From the real time video, the face images are grabbed and a modified geometric projection method is proposed to extract the mouth region based on the distribution relationship with the face Region Of Interest (ROI). After mouth localization, a new pixel-based approach is proposed to extract the outer lip contours. The performance of the lip tracking method using adaptive thresholding is evaluated in real time in the normal room environment, and this method achieves 98% recognition rate.

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Mouth Localization Geometric Projection Method Lip Tracking Adaptive Thresholding.