Head motion estimation from four feature points

According to facial features data to for head action determination of linear method, the method including following steps: gets first site facial image, and in the first site image in the detection head; in above of first site facial image in the detection four a points p of location, this four a points for P={p1,p2,p3,p4}, and PK= (XK,YK); gets second site facial image, and in the second site image in the detection head; in second site facial image in the detection four a points P' of location, this four a points for P' ={P1',p2',p3',p4'}, and pk'= (xk',yk'); p and P' to determine the movements of the head, the motion by panning vector rotation matrix r t. Top line determination of an equation (formula (I)), the formula (II) representing the rotation of the camera.