实时多媒体通信的同步模型研究

本文在对同步信息进行分类和分析的基础上，分析了ＯＣＰＮ模型的局限性，提出了改进的多媒体同步模型ＲＯＣＰＮ。通过在节点中引入媒体表现时间和同步时间，将媒体的表现与媒体间的同步行为分开，该模型解决了ＯＣＰＮ模型关于媒体内同步与媒体间同步不可兼得的问题。模拟实验表明，使用ＲＯＣＰＮ模型的多媒体流其媒体流内同步指标和媒体流间同步指标均明显优于使用ＯＣＰＮ模型的多媒体流，尤其当对象丢失率较高时，ＲＯＣＰＮ模

Study on multimedia synchronization model in realtime communication

The disadvantage of OCPN is pointed out with analysis of synchronization information,and a augmented OCPN model named ROCPN is proposed.By introducing presentation duration and synchronization time to each place,the model process presentation and synchronization of media objects separately.Therefore ROCPN can keep synchronization between different media flows,without losing continuity of each media flow.Furthermore,ROCPN is robust for loss of objects in some extent and can effectively avoid long time disparity of media synchronization.The simulation shows that the parameters of intro media synchronization and inter media synchronization of multimedia flows using ROCPN both are much better than the ones using OCPN,especially in case of high loss rate of media objects.