Tracking of Facial Features Using Deformable Triangles

In this paper we present a novel algorithm to track the facial features using a deformable triangle model. The face is modeled as an isosceles triangle connecting the eyes and lips which are called as features of interest (FoI). A maximum likelihood estimator is used to estimate the position of such a triangle in the image sequences by maximizing the correlation value of the feature template in the image and also the probability that the resulting structure represents a face structure. A method is proposed to remove the noise in the obtained structure by projecting it into a shape subspace of isosceles triangles. Burst error in tracking is removed by using a Kalman filter. The algorithm can successfully locate and track the facial features on two sets of video sequences obtained in the laboratory under normal lighting condition with a cluttered background.