I帧QP设置算法及其在场景变换中的应用  

An Improved QP Setting Algorithm of I Frame and Its Application in Scene Change

作　　者：王海婴[1] 张新发[1] 

机构地区：[1]北京邮电大学信息与通信工程学院,北京100876

出　　处：《北京邮电大学学报》2008年第6期99-103,共5页Journal of Beijing University of Posts and Telecommunications

摘　　要：针对H.264标准,提出一种改进的I帧量化参数(QP)设置算法,以梯度算子来衡量I帧编码复杂度,并由此得到I帧的码率-量化(R-QP)模型.仿真结果表明,改进算法在峰值信噪比(PSNR)性能和码率控制的准确度上均有提高,能获得更为平滑的PSNR曲线图和视觉质量.将此算法应用于场景变换时,跳帧数目大幅度减少,视频质量得到进一步提高.A new quantization parament （QP） setting algorithm of Ⅰframe based on H. 264 is proposed. The improved method establishes a rate-quantization（R-QP） model by using gradient-based picture complexity measure. Simulation shows that by using the proposed scheme, a better rate control accuracy and a higher peek signal noise ratio （PSNR） gain will be achieved. When applied to scene change, the number of skipped frames will be significantly reduced and the overall subjective quality of the reconstructed video will be provided.

关 键 词：码率控制 梯度 场景变换 

分 类 号：TN919.81[电子电信—通信与信息系统]