OBJECT-ORIENTED H.263 COMPATIBLE VIDEO CODING PLATFORM FOR CONFERENCING APPLICATIONS

This paper describes a prototype video coding platform(1) meant for th e conception and testing of multimedia products such as next-generatio n videophones, The platform is largely based on ITU-T Recommendation H .263, with a number of additional object-oriented quality enhancement features which make it especially well suited for very low bit-rate co ding of ''head-and-shoulders'' video material typical of real-time mul timedia applications, video teleconferencing, and video telephony, The se features consist of: 1) segmentation into objects of interest, 2) s egmentation-based prefiltering, 3) model-assisted rate control, 4) ada ptive vector quantization, and finally 5) segmentation-based postfilte ring, In the spirit of Recommendation H.263, these enhancements are mo dular and can be selectively turned on or off, thereby enabling a wide variety of coding modes.