Application of H.263+ Video Coding Modes in Lossy Packet Network Environments

The quality of real-time audio and video information transmitted via today’s Internet suffers severely from often significant packet losses. While this problem is well understood and solved for existing audio coding schemes, support from the video coding standards themselves is required for video streams. This paper presents the newly introduced error resilience mechanisms built into the second version of H.263 (1998), known under its working name H.263+, and addresses the corresponding packetization format issues that together significantly improve the image quality at packet loss rates up to 20 per cent. In particular, it is support from the video coding algorithm itself peered with appropriate transport layer mechanisms that leads to significant improvements of perceived image quality for communicative as well as retrieval applications at moderate bit rates up to some 100 kbit/s.