Any real-time interactive video coding algorithm used over the Internet needs to be able to cope with packet loss, since the existing error recovery mechanisms are not suitable for real-time data. In this paper, a robust H.263+ video codec suitablefor realtime interactive and multicast Internet applications is proposed. Initially, the robustness to packet loss of H.263 video packetised according to the RTP-H.263+ payload format specifications is assessed. Two techniques are proposed to minimise temporal propagation - selective FEC of the motion information and the use of Periodic Reference frames. It is shown that when these two techniques are combined, the robustness to loss of H.263+ video is greatly improved.
James T. Chung-How, David R. Bull