Mesh Routing for Error Resilient Delivery of Multiple-Description Coded Image/Video Content

Multiple Description (MD) source coding is a technique that breaks a media stream into equally important sub-streams which can be sent over different paths for protection against channel errors in wireless networks. In this paper, we explore the possibility of sending the descriptions through different paths and intermediately merging them to exploit recovery of the corrupted descriptions from the uncorrupted ones before reaching the destination, thereby increasing the quality of received media at the destination. We first analytically model the end-to-end distortion of MD coded multipath transmission as a function of the path parameters and prove that intermediate recovery achieves an improvement of up to 9.2% in end-to-end distortion compared to traditional multipath transport. We then formulate the mesh route construction as a cross-layer optimization problem. Since the problem is highly complex, we propose an efficient heuristic routing strategy. We show that using this routing strategy, good paths (with up to 2 intermediate recovery nodes) can be constructed to achieve a lower distortion compared to the case without intermediate recovery.