H.264码率控制算法研究

Research on H.264 rate control algorithm

针对JVT-G012的基本单元层码率控制中复杂度的估计部分没有充分利用已编码帧的时空相关性的缺点,使用新的模型将当前帧已编码的基本单元MAD值引入到原有MAD模型中进行复杂度估计,充分利用已编码帧的时空相关性,使复杂度的估计更准确。实验结果表明,该改进模型PSNR提高0.01～0.08dB,视频图像质量更好,编码时间也有不同程度的下降,实时性提高,编码生成的Bits数降低,节省传输带宽。

In the basic unit layer rate control of JVT-G012,space-time correlation in the encoded frame isn＇t been full used in the complexity estimate part,to rectify this shortcoming,this article uses the new model to implement the complexity estimates,the MAD value of the basic unit layer in the current encoded frame will be introduced into the original MAD model.This improvement can be a good use of space-time correlation of the encoded frame,complexity estimates is more accurate.The experimental results show that the improved model makes the video image quality better,PSNR increases 0.01～0.08dB,the time of encoding decrease,and the Bits decrease,save the transform bandwidth.