视频流媒体的QoS特征分析及质量保证

网络数据传输的质量保证一般可分为空间域保证和时间域保证。空间域保证是传输数据的量的保证,取决于网络的带宽和丢失率特征;时间域的保证是对传输数据的时效性保证,取决于网络的延时和延时抖动特征。传统的数据媒体对网络传输的空间域保证有严格的要求,而没有严格的时间域保证要求。它不允许有数据丢失,但能够容忍一定的时间延时和延时抖动;而视频流媒体与此相反,它能够容忍一定的数据丢失,但要求较为严格的延时和延时抖动保证。这篇文章主要对视频流媒体数据传输的空间域特征和时间域特征进行讨论,分析其对视频流媒体的质量影响,为流媒体的网络传输QoS保证策略提供有价值的参考。

QoS Characteristics of Video Stream Delivery Analysis and Assurance

Quality assurance of delivery information on the network can be divided into Space Domain Quality and Time Domain Quality.Space domain quality is the information amount required by the decoder that the video information could be accurately recovered,which is determined by the bandwidth and loss-rate of the network.Time domain quality is effectiveness for given the period of time ,which is fixed on the delay and delay-jitter of the network.General data application is strict to require for Space Domain Quality assurance but not for Time Domain Quality,and it cannot al-low any data-loss.However,the video stream can tolerate some degree of the data-loss,but it is strict for delay and de-lay-jitter.This paper,discusses QoS characteristics of video stream delivery,and analyzes the effects for the video quali-ty,in order to provide a reference for QoS policies of network to delivery video stream.