Estimation of the chin and cheek contours for precise face model adaptation

For semantic coding of videophone sequences at very low bit rates, the adaptation of a face model to automatically estimate facial features is necessary. In this contribution, an algorithm for the automatic estimation of the chin and cheek contours of a person is presented. The chin and cheeks are represented by a deformable template consisting of parabolas. Cost functions are established and minimized to find the best fit of the template to the chin and cheek contours of the person. In all examined frames of the videophone sequences "Akiyo" and "Claire", the manually determined real contour of the chin and the cheeks is approximated by the estimated contours with good accuracy. In more than 60% of all frames, no deviation between the real contours and the estimated contours occurs.