Source adaptive TCP-compatible rate control for video over the Internet
This paper describes a rate control algorithm that captures not only the behavior of TCP's congestion control avoidance mechanism but also the delay constraints of real-time streams. Building upon the TFRC (TCP-friendly rate control) protocol (see Floyd, S. et al., Proc. ACM SIGCOMM'2000, p.43-56, 2000), a new protocol based on RTP/RTCP has been designed in order to take into better account the multimedia flow characteristics in the estimation of the bandwidth prediction model parameters. Given the current channel state, the encoder and decoder buffer states and the delay constraints of the real-time video are translated into encoder rate constraints. This global rate control model, that encompasses the source buffer model as well as the end-to-end delay characteristics, allows significant reduction of source timeouts, hence minimizes the expected distortion, for a comparable usage of the TCP compatible predicted bandwidth.