Receiver-Controlled Joint Source/Channel Coding on the Application Level, for Video Streaming over WLANs

摘要

The proportion of real-time traffic, being transported over internet protocol (IP) networks, appears to be ever increasing. Real-time traffic may, for example, be video and audio, which have real-time constraints such as maximum delay and delay jitter. Such requirements can be hard to satisfy in a wired infrastructure, and are even more so in a wireless network. Therefore there is a need to make transmission over wireless local area networks (WLANs) more reliable. The aim of this paper is to outline a proposal of such a scheme, which enables efficient transmission of MPEG-4 video over an IEEE 802.11b WLAN, and to experimentally verify its efficiency. Receiver-driven layered multicast has been proposed before, for dealing with band limitations and environments with heterogeneous terminals. We extend these ideas to handle packet loss, by adding receiver-driven unequal error protection (UEP). The proposal can be viewed as receiver-controlled joint source/channel (JSC) coding on the application level.