Distortion Optimized Mobile Multiparty Video Conferencing

This paper focuses on concurrent real-time multimedia group communication in wireless environment and proposes a video conferencing system to support multiparty streaming video communication on mobile devices. The proposed solution extends session initiation protocol (SIP) to support multicast session negotiation and uses mobile multicast in IP layer for media data distribution. Since wireless network access is shared by multiple video streams, efficient utilization of wireless bandwidth on mobile device is important, especially for real-time video conferencing application with high data rate and stringent delay requirements. In this paper, the rate allocation among multiple group sessions is considered as an optimization problem with the constraints of video quality and wireless link capacity. The proposed rate allocation benefits from lowering bandwidth cost while network degradation is detected and hereby avoids network congestion. The performance of the proposed solution is evaluated in NS-2; the simulation result shows that our scheme can reduce the average packet loss ratio and improve the overall video quality in mobile multiparty video conference.