Perceptual ARQ for H.264 video streaming over 3G wireless networks

This paper presents a new ARQ algorithm for video streaming over wireless channels. The algorithm takes into account the perceptual and temporal importance of each packet to determine the packet scheduling which maximizes the perceived quality. A simple and flexible function to combine the perceptual importance with the real-lime constraints of each packet to determine which is the best packet to transmit at each transmission opportunity is proposed. The perceptual importance is evaluated using the analysis-by-synthesis technique. The performance of the proposed algorithm has been analyzed by simulating the transmission of H.264 encoded sequences over a 144 kbit/s UMTS channel and compares the proposed method with time-driven ARQ techniques, using PSNR as distortion measure. The results show that for the considered channel conditions the proposed method delivers gains up to 2 dB with respect to the time-driven ARQ technique.