Research And Implementation On Rate Control Algorithm For H.264 Based On R-D Model

H.264 rate control is an interesting problem that has motivated numerous possible solutions as a reason of Standards don't limit the rate control algorithm. The challenge lies in determining a quantization parameter Qp that will be used for both the rate-distortion (R-D) optimization process and the quantization of transform coefficients.In this paper,starting with the discussion of classical Rate control algorithm for H.264,we considered the algorithm itself,Rate Distortion Optimization,Lagrangian Optimization and proposed a simple yet effective rate control scheme.After we do reserach on the standard of H.264 rate control algorithm and RDO algorithm,we do the follow reseach:First,based on the conclusion of the existing rate control algorithm,we compared with these classical proposals, made an analysis of the potential point to improve.Second,discussing from the classical rate distortion model,we discribed the feature of the model and the utilization of rate control algorithm in detail. We attempted to set up model in another way, which can also control the rate effectively. We also divided the coding rate into header and residual information on the basis of the unique features of H.264.,related to the relationship of R,D and QP.Last, from experiments with several video sequences, we found that our rate control scheme is capable of effective rate contorl with minimal model updates during encoding.The proposed rate control scheme adapts quickly to the characteristic of the source data and is particularly effictive at controlling the rate of videos with high and unpredictable motion content.