ADAPTIVE RATE CONTROL ALGORITHMS FOR LOW BIT RATE VIDEO UNDER NETWORKS SUPPORTING BANDWIDTH RENEGOTIATION

This paper presents new adaptive H.263+ rate control algorithms for video streaming and interactive video applications under networks supporting bandwidth renegotiation, which can communicate with end-users to accommodate their time-varying bandwidth requests during the data transmission. That is, the requests of end-users can be supported adaptively according to the availability of the network resources, and thus the overall network utilization can be improved simultaneously. They are especially suitable for the transmission of non-stationary video traffics. The proposed rate control algorithms communicate with the network to renegotiate the required bandwidth for the underlying video which are measured based on the motion change information, and choose their control strategies according to the renegotiation results. Unlike most conventional algorithms that control only the spatial quality by adjusting quantization parameters, the proposed algorithms treat both the spatial and temporal qualities at the same time to enhance human visual perceptual quality. Experimental results are provided to demonstrate that the proposed rate control algorithms can achieve superior performance to the conventional ones with low computational complexity under networks supporting bandwidth renegotiation. (C) 2002 Elsevier Science B.V. All rights reserved.X1112sciescopu