NURBS curve controlled modelling for facial animation

Abstract

Computer facial animation is a challenging and potentially important area. In this paper, we propose a novel method in which the non-uniform rational B-spline (NURBS) curve is used as a control mechanism to model and animate human facial expressions. A geometric similarity between the modification of NURBS curves and the movement of muscles is identified. Based on the geometric similarity, NURBS curves are constructed so that modifying these curves can closely simulate the movement of facial muscles. The control points of the NURBS curves are positioned according to facial anatomy and the NURBS curves are geometrically associated with a generic polygon mesh representing the face. The weights can then be changed or the control points repositioned to simulate various facial expressions. The proposed method is significantly different from existing facial animation methods and represents a new approach in geometric modelling for computer graphics.