Low-delay and erior-robust wireless video transmission for video communications

Video communications over wireless networks often suffer from various errors. In this paper, a novel video transmission architecture is proposed to meet the low-delay and error-robust requirement of wireless video communications. This architecture uses forward-error-correction coding and automatic repeat request (ARQ) protocol to provide efficient bandwidth access from wireless link. In order to reduce ARQ delay, a video proxy server is implemented at the base station. This video proxy not only reduces the ARQ response time, but also provides error-tracking functionality. The complexity of this video proxy server is analyzed. Experiment shows that about 8.9% of the total macroblocks need to be transcoded under a random-error condition of 10(-3) error probability. Because H.263 is the most popular video coding standard for video communication, we use it as An experiment platform. A data-partition scheme is also used to enhance error-resilience performance. This architecture is also suitable for various motion-compensation-based standards like H.261, H.263 series, MPEG-1, MPEG-2, MPEG-4, and H.264. For "Foreman" sequence under a random-error condition of 10(-3) error probability, luminance peak signal-to-noise ratio decreases only 0.35 dB, on average.