摘要
视频的实时传输存在带宽、传输延迟、包丢失率等方面的要求,而当前的Internet环境下未提供任何QoS(服务质量)服务,所以一个有效的视频传输系统必须自适应于网络状况的动态变化。在充分发掘MPEG-4特性的基础上,该文构造了一个基于MPEG-4的视频流传输框架。通过使用带宽预测、自适应速率调整、SFEC纠错、错误隐藏等机制使视频的传输能够自适应于网络状况的动态变化。同时,提出了一种基于优先级的速率调整算法,克服了传统基于R-D理论的速率调整算法对媒体源支持单一的缺点。试验结果表明,该系统在低比特率、网络状况动态变化的环境中能取得良好的视频传输效果。
Delivering real-time video has the requirements of bandwidth,delay and loss.However,current Internet does not offer any quality of service guarantees,then an efficient video transmitting must be compatible with network condition.This paper proposes a MPEG4-based video delivery system.On the base of exploit MPEG-4standard,the video delivery system can adapt video stream to the varying network condition by using bandwidth estimation,adaptive rate shape,SFEC,error concealment techniques.Specifically,a Priority-Based rate shape algorithm is developed,which is more efficient than the R-D based rate adaptive coding.Simulation results demonstrate that this system can achieve perceptual video quality under low bit-rate and varying network condition.
出处
《计算机工程与应用》
CSCD
北大核心
2003年第35期152-154,共3页
Computer Engineering and Applications
