Because a linear model is usually used to predict the MAD and the QP quantization is the same in the JVT G012

which costs too much in operation and cant avoid deviation

an improved rate control algorithm for the basic unit layer enconder is presented. Firstly

the MAD is predicted by a new weighted time and space model. Secondly

macroblock layer rate control strategy is used to distribute target bits. Finally

the quadratic RQ model in the JVT G012 is still adopted to calculate QP. Simulation results show that the PSNR is effectively elevated and lower bit rate is achieved in the H.264 encoder by using the new algorithm.