一种基于视觉感知的H.264码率控制算法

针对目前视频编码标准H.264的码率控制算法未考虑人眼视觉感知、易导致编码后视频图像质量波动的不足,提出了一种基于视觉感知的H.264码率控制算法.首先,设计了像素域的恰可察觉失真模型.在此基础上,根据各帧的恰可察觉失真的大小进行帧层比特分配.其次,建立了基于结构相似度的率失真模型,并采用此模型设计了基本单元层（basic unit,BU）的比特分配方案.最后结合二次速率-量化模型得到量化参数.实验结果表明,该算法与目前H.264中典型的码率控制算法相比,错误率降低了0.2％.

Visual Perception Based Rate Control Algorithm for H.264

Due to that the conventional rate control algorithm for the latest video coding standard H.264 does not take into account the human visual perception and many result in video quality fluctuation,a visual perception based rate control algorithm （VP-RCA） for H.264 is proposed in this paper.First,bit allocation to frame is related to the Just Noticeable Distortion of frame and the rate control is performed by adaptive rate-distortion optimal.Second,the structural similarity index as the quality metric for rate-distortion modeling and the optimum bit allocation is performed in basic unit （BU） layer.And the value of quantization parameter （QP） is computed by exploring quadratic rate-quantization （R-Q） model.Experimental results show that the proposed rate control algorithm can reduces the bit-rate error by up to 0.2％ comparisons with the typical rate control algorithms.