A joint source coding and networking scheme for video streaming over wireless LANs

Abstract

We present a joint source coding and networking technique for video delivery over wireless local area networks. The objective is to improve the end-to-end video quality with the constraint of network throughput. The proposed video transport scheme integrates several networking and coding components, including load-aware multipath routing, class based queuing (CBQ), and scalable (or layered) video source coding. An effective 3D-OCTREE video coder is used to generate the multilayer source data streams. The coded bitstreams can be segmented into multiple substreams, each with a different contribution towards the final video reconstruction. The underlay wireless ad hoc network is designed to support differentiated service (DiffServ). A multipath routing with load-aware route discovery is used to find multiple routes from the source to the destination with different quality of service (QoS) characteristics. The video substreams will be distributed among these paths according to their QoS priority. CBQ is applied to all intermediate nodes, which gives preference to important substreams. Through this approach, the scalable source coding techniques are incorporated with DiffServ networking techniques so that the overall system performance is effectively improved. Preliminary simulations have been conducted on the network simulator (ns-2), and significant improvements over traditional wireless LAN transport schemes have been observed.