Robust H.263 video coding for transmission over the internet

Abstract

The widely popular World Wide Web along with advances in desktop computers has brought the world into a new age of computing and communications. Low bit-rate video applications across the Internet are quickly emerging. The ITU-T H.263 standard was designed for low bit-rate video conferencing across phone lines and is an ideal candidate to be extended for Internet video applications. This paper focuses on the error robustness issue of compressed H.263 video streams when transmitted over the Internet. The traditional approach of inserting intra-coded frames increases the error resilience at the expense of bursty output traffic, lower picture quality, and uneven frame dropping. By extending the macroblock force update feature of the H.263 standard, we developed a scheme that complies with the standard and increases the robustness of the video stream. This macroblock updating scheme analyzes the temporal dependencies of macroblocks in successive frames and selectively updates the macroblocks which have the most impact on later frames. The performance evaluation of the proposed technique demonstrates that it achieves a good balance between error recovery speeds and video quality.