Greta: A Simple Facial Animation Engine

Abstract

In this paper, we present a 3D facial model compliant with MPEG-4 specifications; our aim was the realization of an animated model able to simulate in a rapid and believable manner the dynamics aspect of the human face. We have realized a Simple Facial Animation Engine (SFAE) where the 3D proprietary facial model has the look of a young woman: “Greta". Greta is the core of an MPEG-4 decoder and is compliant with the “Simple Facial Animation Object Profile" of the standard. Greta is able to generate the structure of a proprietary 3D model, to animate it, and, finally, to render it in real-time. Our model uses a pseudo-muscular approach to emulate the behaviour of face tissues and also includes particular features such as wrinkles and furrow to enhance its realism. In particular, the wrinkles have been implemented using bump mapping technique that allows to have a high quality 3D facial model with a relative small polygonal complexity.