Packet Loss Recovery for Streaming Video

While there is an increasing demand for streaming video applications on the Internet, various network characteristics make the deployment of these applications more challenging than traditional TCP-based applications like email and the Web. Packet loss can be detrimental to compressed video with interdependent frames because errors potentially propagate across many frames. While latency requirements do not permit retransmission of all lost data, we leverage the characteristics of MPEG-4 to selectively retransmit only the most important data in the bitstream. When latency constraints do not permit retransmission, we propose a mechanism for recovering this data using postprocessing techniques at the receiver. We quantify the effects of packet loss on the quality of MPEG-4 video, develop an analytical model to explain these effects, present a system to adaptively deliver MPEG-4 video in the face of packet loss and variable Internet conditions, and evaluate the effectiveness of the system under various network conditions.