Animation data compression in MPEG-4: interpolators

In this paper, we propose new technologies to compress the interpolator nodes in VRML/MPEG-4 BIFS (binary format for scene). Interpolators are used to animate the 3D objects in a VRML/MPEG-4 BIFS scene. For interactive applications with quite a few animated 3D synthetic objects, two components are dominant in the amount of data to represent the animation: 3D object and its animation. In the current MPEG-4, 3D model coding (3DMC) yields a high compression ratio with reasonable quality for the 3D object, while predictive MFField coding (PMFC) yields a moderate compression ratio with reasonable quality for the animation data. The proposed techniques are to provide a high compression on animation data and have been adopted to MPEG-4 system amendment 4 (AFX/MUW).