Abstract: Methods and systems for rate-based flow control between a sender and a receiver are disclosed. A receiver performs TCP-like flow control calculations based on packets received from a sender. The receiver calculates a transmission rate and forwards the transmission rate to the sender. The sender sends packets to the receiver at the rate calculated by the receiver. Thus, rather than having sender-based flow control as in TCP, the receiver controls the rate at which packets are delivered.

Abstract: Methods and systems for rate-based flow control between a sender and a receiver are disclosed. A receiver performs TCP-like flow control calculations based on packets received from a sender. The receiver calculates a transmission rate and forwards the transmission rate to the sender. The sender sends packets to the receiver at the rate calculated by the receiver. Thus, rather than having sender-based flow control as in TCP, the receiver controls the rate at which packets are delivered.

Abstract: Real-time interactive video transmission in the current Internet has mediocre quality because of high packet loss rates. Loss of packets belonging to a video frame is evident not only in the reduced quality of that frame but also in the propagation of that distortion to successive frames. This error propagation problem is inherent in any motion-based video codec because of the interdependence of encoded video frames. Since packet losses in the best-effort Internet environment cannot be prevented, minimizing the impact of these packet losses to the final video quality is important. A new forward error correction (FEC) technique effectively alleviates error propagation in the transmission of interactive video. The technique is based on a recently developed error recovery scheme called Recovery from Error Spread using Continuous Updates (RESCU).

Abstract: Methods and systems for performing packet loss recovery when transmitting compressed video over a lossy packet-based network include transmitting packets of compressed video data from a sender to a receiver. In response to detecting lost or erroneously received packets, the receiver transmits a retransmission request to the sender. In response to receiving the retransmission request, the sender changes the periodic temporal dependency distance of a frame to be transmitted such that the frame depends on the frame associated with the retransmitted packets. The receiver receives the retransmitted packets and restores the frame corresponding the retransmitted packets in a frame buffer. The receiver uses the restored frame to decode a frame transmitted after the retransmitted packets.

Abstract: A new retransmission-based error control technique that does not incur any additional latency in frame playout times and is suitable for interactive video applications. This retransmission technique combined with layered video coding yields good error resilience for interactive video conferencing. The technique exploits the temporal dependency of inter-coded frames and can be easily incorporated into motion-compensation based coding standards such as MPEG and H.261, achieving very good compression efficiency.