When media is streamed over best-effort networks, a buffer at the client protects against playout interruptions due to variations in the data arrival rate. While the amount of protection offered grows with the size of the client’s buffer, so does the latency that is introduced. In this paper we show how adaptive media playout (AMP) - the variation of the playout speed of media frames depending on the condition of the channel - allows smaller buffer sizes and correspondingly smaller delays for a given level of protection against buffer underflow. We demonstrate this with the results of Markov chain analyses and with simulations. In addition, we consider AMP as a form of receiver-driven rate scalability, allowing clients access to streams encoded at higher source rates than their connections would ordinarily allow.
Mark Kalman, Eckehard G. Steinbach, Bernd Girod