Resolution Scaled Quality Adaptation for Ensuring Video Availability in Real-time Systems

Online videos are one of the most prevalent forms of communication over the Internet because humans are attracted to visual stimulations. Multimedia services, especially real-time services, require data to arrive on time. Unlike any other transmissions, video streaming needs to be monitored and adapted to bandwidth, when the video stream passes through the best-effort environment. A guaranteed QoS (Quality of Service) is essential in all real-time applications. This paper presents a contextaware mechanism, which improves the QoS of real time video transmission, over wireless networks. This proposed RSQA system ensures video availability even when the bandwidth is low. Drawbacks to other solutions for saving bandwidth in real-time include being: 1) too expensive due to requiring a priority based router (in the case of proxy based and frame prioritization approaches); 2) too complex; 3) not appropriate for real-time systems. This RSQA system succeeds in being of low complexity, appropriate for real-time systems and cost effective (not requiring a priority based router to function). This RSQA system is independent of wireless technology making, thus it appropriate for use in a heterogeneous environment as well. Whenever a user experiences packet loss or a delay in receiving a video, the server will be notified about the congestion and decrease the video quality to make the video available at low bandwidth. The decision regarding the needed QoS parameters and the rate control is based on context information (available bandwidth). The RTP (Real-time Transport Protocol) based streaming is simulated and verified by an Eclipse simulator and Java using an MJPEG standard. Results show that the QoS parameters of video transmission were improved considerably by this RSQA system.