RD-Based Adaptive UEP for H.264 Video Transmission in Wireless Networks

Video streaming is challenging in wireless networksdue to the high loss rate and limited bandwidth. Invideo sequences, different part has different importance forreconstruction. Based on H.264 error resilient tool of datapartitioning, we apply UEP (Unequal Error Protection) todifferent data partitions. RS (Reed Solomon) coding is usedfor data partition A, whereas simple repeat-packet coding fordata partition B and C. An RD (Rate-Distortion) model is thenestablished to optimize the bit rates distributed among differentdata partitions and parity codes, in order to minimize the endto-end distortion. The model accuracy is verified. Based on theRD model, an adaptive UEP framework is proposed, underwhich the strengthes of RS codes and repeat-packet codes, andthe quantization parameters of the source codes are determineddynamically according to the network conditions in termsof available bandwidth and packet loss rate. The extensiveexperiments show that the proposed scheme can adapt to thenetwork conditions very well, graceful reconstruction qualitydegradation can be achieved against a large range of packetloss rate and available bandwidth.