Abstract: This paper presents a new frame-level rate control scheme for H.264/AVC with joint rate and distortion models. A rate model for the header information is developed to estimate header bits more accurately. The number of header bits is modeled as a function of the number of blocks and the average bits of MVs. A new Rate-Distortion（R-D） model for header information and texture is proposed to joint header-texture rate model and a distortion model. An accurate estimation method is proposed to improve rate distortion performance. When compared with the rate control scheme G012 which is adopted by the latest JVT H.264/AVC reference model JM10.2, the proposed rate control algorithm could improve the matching rate between actual bits and targets ones by up to 98.06%. The average luminance PSNR of decoded video is increased by up to 0.27 dB.

Key words: rate distortion, rate control, header information, target rate

摘要： 在H.264/AVC视频编码框架下，基于联合率失真模型，提出了一种新的帧级码率控制方法。利用分块数量和平均运动矢量信息，发展了一种精确的头信息估计模型；联合头信息与残差信息模型，并结合残差失真模型，提出新的联合头信息与残差率失真模型；利用精确的估计方法进一步提高率失真性能。相对于最新的JVT H.264/AVC参考软件JM10.2中采用的JVT-G012方法，该方法提高了实际码率与目标码率之间的匹配率达到了98.06%，重构视频的平均亮度PSNR值增加了0.27 dB。

关键词: 率失真, 码率控制, 头信息, 目标码率