Real Time Segmentation of Lip Pixels for Lip Tracker Initialization

We propose a novel segmentation method for real time lip tracker initialisation which is based on a Gaussian mixture model of the pixel data. The model is built using the Predictive Validation technique advocated in [4]. In order to construct an accurate model in real time, we adopt a quasi-random image sampling technique based on Sobol sequences. We test the proposed method on a database of 145 images and demonstrate that its accuracy, even with a few number of samples, is satisfactory and significantly better than the segmentation obtained by k-means clustering. Moreover, the proposed method does not require the number of segments to be specified a priori.