【摘要】 关于多媒体技术优化问题,针对易错视频传输中存在容错机制消耗大量信道资源的问题,为了提高视频服务质量,采用NS2和编解码器设计实现了一套实时无线视频传输仿真系统,提出了一种基于用户满意度的视频部分重传控制算法UP-CA,以感知得到的终端用户视频满意度为基准,根据最小化带宽-失真模型和视频自身特性,选取出错数据帧的错误恢复模式。仿真结果表明,相对于ARQ算法,UPCA能有效减少带宽,降低延迟。改进的系统极具扩展性,证明视频容错控制算法可为进一步优化控制提供依据。更多还原

【Abstract】 To solve the problem that the traditional fault-tolerance mechanisms consume large amounts of channel resources in the error-prone video transmission,we first design and implement a real-time simulation system of wireless video transmission by using NS2 and H.264 codec,and then propose a video partial retransmission control algorithm based on user satisfaction(UPCA) in this system,that is,to take the end-user video satisfaction as a benchmark,and select the error recovery mode by the minimized value of the Bandwidth-Distortion model and the video self-characteristics.The simulation results show that,compared with ARQ algorithm,UPCA can effectively reduce the bandwidth consumption and the time delay.Meanwhile,the system has high scalability,and has great significance for the further study of the fault-tolerant control algorithm.更多还原