共查询到20条相似文献,搜索用时 171 毫秒
1.
2.
3.
4.
文中提出了一种基于IP网络具有双重QoS保证的VOD流媒体系统结构.此结构使用RSVP协议对流媒体预留资源,资源预留采用基于节的资源管理方法;服务器端通过RTP协议传输实时多媒体数据流,RTCP协议监视传输服务质量进行动态QoS控制,因此对基于IP网络的VOD系统的流媒体传输QoS提供了双重保证.其客户端使用SDP协议取得流媒体文件描述信息和组播地址,通过RTSP协议与流媒体文件服务器交互,建立和控制多媒体会话. 相似文献
5.
6.
基于RTCP包解析的音频QoS控制研究 总被引:1,自引:0,他引:1
本文提出了基于流媒体传输协议的应用策略和方法.对基于RTP/RTCP协议的音频QoS控制进行了研究并提出一种基于RTCP包解析的提高QoS的控制方案。 相似文献
7.
由于网络传输引起的视频流媒体质量损失(称为传输失真)是流媒体QoS中最重要的参考指标,通常只能在终端系统解码后获得.本文根据视频流媒体编解码、错误隐藏、错误扩散等理论进行分析,提出了一个视频流媒体传输失真模型,谊模型可以在发送端通过网络传输质量和视频流媒体特性参数估算视频流媒体的最终表现质量,可以为流媒体同步、控制算法提供定量的参考指标.该模型针对常见的视频流媒体处理机制进行建模,并不局限于特定的编解码格式,具有更广泛的实用价值. 相似文献
8.
无线流媒体传输技术可以满足用户利用无线网络实现在线视频播放,但较恶劣的无线网络环境使在线流媒体,特别对于需实况转播的流媒体系统,视频画面可能出现延迟、抖动和失真等问题,这在很大程度上影响了用户观看视频的直观感受。为了降低无线流媒体传输技术对无线网络环境的要求,提高无线视频传输的QoS(Quality of Service,服务质量),在国外视频分帧传输的思想上,提出一种FSMS(Frame Splitting Multichannel Streaming,分帧多信道传输)无线流媒体传输模型,并且基于该模型在Android移动平台上设计并实现了一整套无线流媒体传输系统。系统测试表明,即使在大量帧丢失的较恶劣网络环境下,运用此模型可以显著提高无线流媒体视频播放的流畅性。 相似文献
9.
Internet视频业务的普及和用户越来越高的服务需求推动了实时流媒体业务的迅速发展,流媒体业务的服务质量(QoS)成为业界研究的热点.由于网络的复杂性,流媒体的实时调度控制算法是解决流媒体QoS的关键.结合FEC编码技术和Kalman数字滤波技术,提出一种基于QoS的改进FEC调度传输控制算法——QFEC.该算法根据接收方的状态合理调度流媒体业务,并结合Kalman滤波器原理完成传输速率控制.通过算法状态分析,以及实验数据和性能分析表明,该调度算法能够维持视频数据良好的连续传输,降低视频流的丢包率,显著改善流媒体业务的QoS. 相似文献
10.
近年来,随着我国教育信息化的高速发展,校园网上VOD多媒体教学视频流的传输面临着越来越多的服务质量(Quality of Service,QoS)需求。当今的基于Ipv4的网络在流量、延迟和网络带宽管理上功能很弱,不可能给这些流媒体应用提供真正的QoS控制和保证。构建新的Ipv6校园网,在流媒体技术的基础上,结合Ipv6技术与组播技术,才能更好的解决校园网上流媒体传输的QoS问题。 相似文献
11.
The multicast of Streaming Media over the Internet is an important component of many current and future Internet applications.The heterogeneity and lacking of QoS guarantee make the application of this technique a challenge.In this paper,we analyze the difficulties in streaming media multicast design,survey technologies that have been proposed for it.We also discuss several congestion control and error control mechanisms.Finally we present some remained issues for further research. 相似文献
12.
流媒体是指多媒体数据流在网络上一边传输一边播放的一种多媒体通信服务.提供尽力而为服务的Internet不能为流媒体保证网络带宽、传输延迟、分组丢失以及分组错误等,而自适应传输控制机制能够提高流媒体服务的传输服务质量和传输服务的公平性.本文探讨流媒体自适应传输控制技术所涉及的各个方面,包括拥塞控制、质量自适应和错误控制. 相似文献
13.
Streaming media from the Internet is a successful application for end-users. With the upcoming success of mobile devices
and home networking environments, cooperation among users will become more important in the future. To achieve such cooperation,
explicit middleware standards have been defined. On the other hand, Internet conferencing applications do not handle collaborative
streaming sessions with individual control for each user. We propose a new concept for cooperation exemplary for collaborative
media streaming using IETF multimedia session control protocols together with a proxy architecture. This concept enables both
synchronization among clients and flexible control to individual users. 相似文献
14.
WANG Guijin ZHANG Qian ZHU Wenwu & LIN Xinggang . Department of Electronic Engineering Tsinghua University Beijing China . Microsoft Research Asia Beijing China Correspondence should be addressed to Wang Guijin 《中国科学F辑(英文版)》2004,47(2):246-259
With the growth of the Internet and abundant network resources, video streaming is becoming one of the increasingly important Internet applications. However, the current IP-based network provides only a single class best effort service. Video packet can be regarded as a packet loss by the video decoder either due to network congestion or due to exceeding the maximum delay threshold. It remains an open challenging task as to how to cope with the packet loss in the video streaming over the Int… 相似文献
15.
16.
流媒体传输已经成为Internet通信中的重要组成部分之一,虽然它可以从代理缓存中受益,但传统的代理缓存策略不能满足媒体对象所特有的特征,必须提出新颖的缓存方法。该文讨论了代理对视频流的缓存,包括前缀、分块和部分视频对象的全部缓存的问题和挑战。同时研究了缓存视频流的代理网络结构,有分布式、层次式和覆盖式,对它们进行了描述和评论,还把缓存和代理网络同组播相结合进行了讨论。 相似文献
17.
Enhanced streaming services in a content distribution network 总被引:1,自引:0,他引:1
Cranor C.D. Green M. Kalmanek C. Shur D. Sibal S. Van der Merwe J.E. Sreenan C.J. 《Internet Computing, IEEE》2001,5(4):66-75
Prism's content naming, management, discovery, and redirection mechanisms support: high-quality streaming media services in an IP-based content distribution network. IP content distribution networks (CDNs) are special-purpose networks that provide scalability by distributing many servers across the Internet “close” to consumers. Prism (Portal infrastructure for Streaming Media) is a CDN architecture for: distributing, storing, and delivering high quality streaming media over IP networks. The Prism-based stored-TV (STV) service allows users to select content based on the program's name as well as the time it was aired. Content stored inside the network is accessible throughout the whole Prism infrastructure. For example, a user in the US can access European TV content both live and on-demand. Prism also allows users to specify content to be stored in a “network-VCR” type service. The authors introduce the components of the Prism architecture 相似文献
18.
随着互联网流媒体应用的增多,流媒体流量在互联网总流量中所占比例越来越大。流媒体流量具有时延敏感和容忍丢包等特点,通常采用UDP协议传输;UDP流量是对TCP/AQM模型的干扰流量,但现有针对TCP长流设计的主动队列管理算法缺乏抗击UDP流量干扰的能力,不能适应互联网视频和音频流量日益增多的局面。利用TCP/AQM模型,设计了一个具有最小平方误差积分,且相角裕度在30°至60°之间,幅值裕度在2至5之间的基于PID控制器的主动队列管理算法ISE-GPM-PID。该算法对UDP流量具有良好的抗干扰能力,能适应互联网流媒体和Web应用日益增多的局面;同时其响应速度快,计算开销小,能用于大时滞网络环境,且鲁棒性好。 相似文献
19.
Qian Zhang Wenwu Zhu Ya-Qin Zhang 《Multimedia, IEEE Transactions on》2001,3(3):339-355
This paper addresses the resource allocation problem for multiple media streaming over the Internet. First, we present an end-to-end transport architecture for multimedia streaming over the Internet. Second, we propose a new multimedia streaming TCP-friendly protocol (MSTFP), which combines forward estimation of network conditions with information feedback control to optimally track the network conditions. Third, we propose a novel resource allocation scheme to adapt media rate to the estimated network bandwidth using each media's rate-distortion function under various network conditions. By dynamically allocating resources according to network status and media characteristics, we improve the end-to-end quality of services (QoS). Simulation results demonstrate the effectiveness of our proposed schemes 相似文献