一种基于TM5模型的改进型码率控制算法

A TM5 Based Improved Rate Control Arithmetic

TM5[1,2]模型是一个世界范围内广泛应用的MPEG编码实现的测试模型，它很好地完成了MPEG的算法实现，为MPEG-1/MPEG-2标准的进一步修改和推广起到了非常重要的作用。因为其主要只是供给标准的算法研究而非商业应用，在免费公开源代码的同时与实际应用存在着一定的差距。实际视频应用中，场景切换经常发生，该文讨论如何改进TM5中的rate control算法，提出了一个分两步的改进型算法,使其克服了无法很好应对场景切换的问题。

TM5 is a test model which is a world-wide implemented successful algorithm application for MPEG-2 standard. It exerts an important influence on the modification and generalization of MPEG-1/MPEG-2. Because the main focus of TM5 is algorithm research, not business application, it has opened free source code and exists some limitation in the practice. It is well known that scene changes often happen in our contacted video information. The first part of this paper discusses how to improve the rate control algorithm of TM5,in order to resolve the scene change problems.