视频业务的短期统计特性

利用动态图象序我研究了ＡＴＭ网络中视频业务和短期统计特性，对视频图象每个宏块经过ＭＰＥＧ压缩后所产生的比特数进行了分析，研究了量化比例因子及量化加权矩阵对业务短期统计特性的影响。统计结果表明，量化比例因子对每个宏块比特数的的概率分布影响最为明显，量化加权矩阵对统计特性的轮廓影响很小，当量化比较精细时图象内容对分布特性的低比特部分影响比较明显，而粗量化时它的影响较弱。

Short Term Statistical Characteristics for Video Service

Short term statistical characteristics of moving image sequences is discussed. To get reasonable results, real time motion image sequences are used, bit numbers of each macroblock after encoding using MPEG compression algrithom is analyzed. In the mean time, the effect of quantiser scale and quantiser matrix to the statistical property is also researched. Simulation result shows that quantiser scale plays a important role in the statistical property, while quantiser matrix has little influence. If small quantiser scale is adopted, image contents will affect the probability distribution at low bit end, and its influence decreases as the quantiser scale is relatively large.