基于MPEG视频流的动态带宽分配算法

ATM是兴起的宽带网标准,基于报文的视频正是宽带网上的一个典型应用.变位率视频的传输方法为恒定的视频质量提供了可能,但是在传输过程中,报文的丢失、延迟和延迟抖动等因素都会影响视频质量,因此有必要提供QoS保证.提出了两种新的在ATM网上进行MPEG视频传输的动态带宽分配算法,一种是动态计算算法,另一种是动态虚拟缓存算法.在这些算法中,根据允许的丢包率,动态地调整MPEG视频带宽以保证QoS.

A Dynamic Bandwidth Allocation Algorithm for MPEG Video Streams

Asynchronous Transfer Mode (ATM) is an emerging standard for broadband networks, packetized video is likely to be one of the most significant high-bandwidth users of such networks. The transmission of variable bit-rate (VBR) video offers the potential promise of constant video quality but is generally accompanied by packet loss, delay and delay jitter which significantly diminishes this potential, so it is necessary to provide requested QoS. In this paper, two new dynamic bandwidth allocation algorithms for MPEG videos over ATM are proposed, one is dynamic measure algorithm, another is dynamic virtual buffer algorithm, in which the authors dynamic adjust the bandwidth of MPEG video sources with a specified allowed cell loss ratios to provide QoS guarantees in an ATM network.