The use of cumulative inter-frame jitter for adapting video transmission rate

The concept of cumulative inter-frame jitter has recently been proposed by the authors. The concept has been shown to correctly predict the frame loss rate at the play-back buffer. In this paper we present two rate control mechanisms to illustrate the use of cumulative inter-frame jitter as a network control criterion to provide the required frame-level QoS. The mechanisms adjust the transmission rate of MPEG-2 video at the source either by discarding B frames randomly or by dropping all B frames throughout congestion period. We combine these mechanisms with different error control strategies for handling network losses, i.e. fixed FEC and adaptive FEC. We study the performance of these mechanisms by simulations. The results reveal two insights. Firstly, dropping B frames allows protection of more important I and P frames for the same amount of bandwidth. This results in lower frame loss rate as observed at the user-level. Secondly, the combination between adapting FEC-level and dropping all B frames outperforms other combinations.