Video Streaming over Wireless Networks

Abstract

As streaming techniques and wireless access networks become more widely deployed, a streaming multimedia connection using wireless networks is becoming increasingly common. However, since current streaming techniques are primarily designed for wired networks, streaming multimedia applications can perform poorly in wireless networks. New streaming techniques have been used to transmit video to different nodes.

On of the most challenging wireless network is the ad-hoc network. A wireless ad-hoc network consists of a number of mobile nodes that temporarily form a dynamic infrastructure-less network. To enable communication between nodes that don't have direct radio connection, each node must function as a wireless router and potentially forward data traffic on behalf of the other nodes. This leads at the end to mesh connectivity.

The mesh connectivity of Ad-hoc networks nodes, having multiple paths between any pair of Ad-hoc networks nodes makes it possible to support multi-path transport, which has been shown to be an efficient way to improve video streaming quality over ad-hoc networks. Recently, a new video coding technique called multiple descriptions coding (MDC) has been successfully developed, which has this kind of nice feature. MDC is capable of encoding a video source into multiple independent streams (or descriptions) such that any subset of these streams at the receiver can be used to reconstruct the original video.

This thesis introduces a modified video coding technique used for wireless ad hoc networks named; Group of Picture Multiple Description (GOP MD) coding. It is a modification to Multiple Description coding that produces two or more bitstreams based on the GOP of the video. GOP MD coding has two important properties; first, it decreases the size of the video after encoding the video this is due to that encoded frames are successive to each other. Second, the GOP MD coding gives a reasonable time to recover the route between the source and the destination.