01/01/1999 09:00 AM

Computer Engineering

The loss curve of a video source characterizes the loss rate of the video stream generated by the source as a function of the allocated buffer size for a given transmission rate. The loss curve is useful in the optimal allocation of resources when the video stream is transmitted over a packet network, so that the desired tradeoff can be reached among the loss rate, bandwidth and the buffer space to be allocated in the network. We present a deterministic algorithm for exact computation of the entire loss curve of a video elementary stream. The algorithm exploits the piecewise linearity of the loss curve and computes only the points at which the slope of the loss curve changes. We also present an extension of the algorithm to MPEG-2 Transport Streams. The algorithm was able to compute the entire loss curve of a 2-hour video elementary stream in approximately 11 seconds on a Sun Ultra-2 workstation. The efficiency of the algorithm makes it suitable for both off- and on-line QoS provisioning in networked video environments.