An efficient video rendering system for real-time Adaptive Playout based on physical motion field estimation

In this paper we present an implementation of an Adaptive Playout System for video rendering. This system can be used for rendering multimedia material that is delivered (in single/multi-cast fashion) to the final user(s) over a “besteffort” network that is unable to guarantee a constant delay in the delivery of the data packets. The proposed solution is an alternative to the “traditional” pre-buffering at the decoder side, which “cushions” the variations of delivery delay, but forces the final user to wait a great deal before the rendering starts and may easily generate annoying freezing of the video in case of pre-buffer underflow. The system can be quite effective in enabling the “zapping” between channels broadcasted over the network by using streaming technology. The system is currently able to run in real time on commercial PCs for the decoding and adaptive playout of CIF sequences, but there is still a great deal of room for further software optimization. A series of informal subjective tests have been conducted to demonstrate the potential of the system.