一种H.264帧层码率控制的改进算法

在H.264的现有帧层码率控制算法的基础上，提出了一种新的基于场景切换的码率控制算法。用P帧亮度分量的MAD比率和YUV三分量的均值相对变化的加权和来表示图像的复杂程度，并以此来分配目标码率、调整量化参数，并且编码时利用比特调整因子对分配的目标码率进行修正。在JM10.2平台下的测试结果表明，与JVT-G012中的算法相比，该算法在精确控制码率的同时，图像的视觉质量也得到了提高。

Improved frame-layer rate control algorithm for H.264

A new rate control algorithm based on scene change was proposed on the basis of H.264 frame-layer. The complexity of image was measured by the weighted sum of the ratio of Mean Absolute Difference (MAD) of P-frame luma coeffecient and the relative changes of YUV's mean value, then the target rate was allocated and the quantitative parameters were adjusted according to the complexity. Meanwhile the target rate can be adjusted by using bits compensative factor. Compared to the algorithm in JVT-G012, the experimental results under the JM10.2 show that both the accuracy of rate controlling and the quality of reconstructed images can be improved if using the algorithm.