视频拨号系统

多媒体通信在市场需求和当今技术相互发展、相互促进下得到迅猛发展，视频拨号（ＶＤＴ）业务方兴未艾，市场潜力巨大。文章介绍了视频拨号业务概念、网络结构、实现方案、经营管理和业务现状。     

基于LTE的宽带多媒体集群技术在公安警务中的应用与发展

相对于传统窄带集群通信技术,基于LTE的宽带多媒体集群系统可以提供更大的无线传输带宽,能够实现无线高清视频监控、视频对讲、视频调度等宽带多媒体业务,可广泛应用于公安业务。文章介绍了基于LTE的宽带多媒体集群系统的架构及其在公安业务领域的典型应用,并且结合公安行业的实际情况,将窄带集群通信与宽带多媒体通信进行有效融合,可实现警用集群通信从窄带网络到宽带网络的平滑演进。     

基于SIP的企业多媒体通信系统的研究

随着VoIP和NGN技术的发展和推广,使为企业提供便宜、集语音、视频、传真、数据共享、即时消息、电子办公支持的通信与业务应用整体解决方案成为可能。本文介绍了一种基于SIP协议的企业多媒体通信系统,重点阐述了该系统的体系结构、系统组成及其在企业网络中的应用。     

无参考视频通信业务质量客观评价方法综述北大核心

近年来,多媒体通信业务飞速发展,对多媒体通信的传输和接收质量进行实时评价和监测有助于端到端业务质量的管理和控制。对视频通信业务质量的评价可通过主观和客观两个方面展开,主要介绍无参考视频质量客观评价方法。首先介绍视频通信中常见的损伤类型,然后分别详细阐述基于像素级、比特流级和混合参数级三种模型的研究现状及相应的标准化进程。     

一种IP网络多媒体传输方案

随着网络技术的迅速发展,图像和视频等多媒体业务已逐渐成为信息处理领域主要的信息媒体形式。IP多媒体业务就是利用IP网络(Internet、Intranet和LAN等)传送多媒体通信的业务,包括语音、数据和视频等,既有非实时业务,又有实时业务,它们对通信网络的要求并不相同。多媒体数据传输具有实时性要求,对网络传输时延和时延抖动等较为敏感。因此,网络必须对多媒体应用的分组进行特殊处理,以保证以最小的时延和时延抖动提供可预见的服务。文中从多媒体通信的特征入手,从QoS的角度介绍了综合业务和区分业务,针对它们各自的优缺点,提出了一种IP多媒体传输的解决方案。     

2010年优秀应用解决方案精选

回顾2010年,由于多媒体通信技术的发展以及市场需求的增长．视频通信的应用得到了前所未有的发展。视频通信系统、视频监控等视频通信业务在政府、电力、军队、金融等得到了广泛的应用。然而随着3G时代的到来,良好的网络基础、使用成本的下降等驱动力促使视频通信进入了一个新的应用阶段。视频通信的应用更加丰富和多元化．这主要表现在以下几方面。     

基于SIP的企业多媒体通信系统的研究

随着VoIP和NGN技术的发展和推广，使为企业提供便宜、集语音、视频、传真、数据共享、即时消息、电子办公支持的通信与业务应用整体解决方案成为可能。本该介绍了一种基于SIP协议的企业多媒体通信系统，重点阐述了该系统的体系结构、系统组成及其在企业网络中的应用。     

移动多媒体通信关键技术研究

移动多媒体通信是未来通信的发展趋势。通过探讨移动多媒体通信数据量大、实时性要求高、无线信遗缺乏QoS保证等特点，介绍了和移动多媒体通信密切相关的几种技术：网络技术；视频编码技术、流媒体技术。     

无参考视频通信业务质量客观评价方法综述

近年来,多媒体通信业务飞速发展,对多媒体通信的传输和接收质量进行实时评价和监测有助于端到端业务质量的管理和控制。对视频通信业务质量的评价可通过主观和客观两个方面展开,主要介绍无参考视频质量客观评价方法。首先介绍视频通信中常见的损伤类型,然后分别详细阐述基于像素级、比特流级和混合参数级三种模型的研究现状及相应的标准化进程。     

基于电视的社交化通信应用解决方案及关键技术研究

详细探讨和介绍了基于电视部署社交化多媒体通信业务的策略,提出与现网结合进行系统部署的方案.为了有效提升电视上的社交体验和通信质量,对屏幕应用适配、视频叠加、实时视频编解码、视频质量自适应等关键技术进行了研究与分析.最后通过实验室测试,验证了本方案在现网应用的可行性.     

Wireless video applications in 3G and beyond

This article surveys wireless video applications that have been commercialized recently or are expected to go to market in 3G (and beyond) mobile networks, mainly covering error control technologies in view of "wireless video." We introduce several related 3GPP standards including circuit-switched multimedia telephony, end-to-end packet-switched streaming, multimedia messaging service, and multimedia broadcast /multimedia service. We also review the supporting technologies for those four applications. The article concludes with a discussion of error control and rate control adaptability to network QoS variation, which is distinct from wired networks and critical to wireless networks. With respect to MBMS, we point out that required cell transmission power is crucial when realizing meaningful multicast coverage, and suggest a system that integrates different unicast and multicast networks, application-layer data repair, and transmission scheduling.     

福建省宽带多媒体通信网集成方案

本文主要介绍福建省宽带多媒体通信网络拓扑结构和业务集成方案。宽带多媒体通信网包括ＡＤＳＬ接入网、ＡＴＭ宽带交换网,应用服务器。目前在福建省宽带多媒体通信网上承载的业务有视频点播和宽带ＷＥＢ浏览、１６９／１６３的传输和路由骨干,帧中继,交互式视频业务（如电视会议,远程医疗）等。     

高速信息网络关键技术—成组广域广播与QoS控制

成组广域广播虚拟网络技术是高速信息网络的关键之一，它直接影响多媒体通信技术的发展与应用，本文综述介绍成组广域广播技术以及与此相关的网络服务品质ＱｏＳ的控制，管理技术的现状，发展趋势以及研究方向。     

Requirements for an IMS-based Quadruple Play Service Architecture

Quadruple play can be understood as the provisioning of high-speed voice, video (live broadcast or on demand services, such as video on demand), and data services over broadband connections with mobility support. Currently, there are several trials of the IP multimedia subsystem deployed worldwide that promise to provide telecommunication and advanced multimedia services. This article focuses mainly on the basic requirements of a cooperative service delivery platform for provisioning quadruple play services. As a result of this research, an IMS-based cooperative service delivery platform is presented. This supports various access technologies to acquire the streaming services. To validate our quadruple play architecture, we implemented a prototype based on DVB-H and UMTS as the access technologies. This prototype is part of the ongoing development of the proposed architecture     

QoE in video streaming over wireless networks: perspectives and research challenges

The deployment of 3G/LTE networks and advancements in smart mobile devices had led to high demand for multimedia streaming over wireless network. The rapid increasing demand for multimedia content poses challenges for all parties in a multimedia streaming system, namely, content providers, wireless network service providers, and smart device makers. Content providers and mobile network service providers are both striving to improve their streaming services while utilizing advancing technologies. Smart device makers endeavor to improve processing power and displays for better viewing experience. Ultimately, the common goal shared by content providers, network service providers, and smart device manufactures is to improve the QoE for users. QoE is both an objective and a subjective metric measuring the streaming quality experience by end users. It may be measured by streaming bitrate, playback smoothness, video quality metrics like Peak to Signal Noise Ratio, and other user satisfaction factors. There have been efforts made to improve the streaming experiences in all these aspects. In this paper, we conducted a survey on existing literatures on QoE of video streaming to gain a deeper and more complete understanding of QoE quality metrics. The goal is to inspire new research directions in defining better QoE and improving QoE in existing and new streaming services such as adaptive streaming and 3D video streaming.     

面向智能物联网的多媒体通信关键技术研究与应用

随着5G大规模商用和人工智能技术的日趋成熟,基础通信服务开启新一轮革新。以固话、手机为代表的传统通信正逐步向场景化智能通信演进,基础通信连接也正在从70亿人和人的连接,向200亿人与人/物的实时音视频连接迈进,呈超清体验、交互智能、终端多态、服务泛在发展趋势。本文提出面向智能物联网的多媒体通信系统架构以及关键技术研究,为新形势下的多媒体通信服务提供创新思路。     

A Bandwidth Control Method Providing Entrance QoS for Multimedia Communication

1 Motivation Nowadays , the QoS provided by the wideband IPnetwork starts at an edge-router and ends at anotheredge-router .Therefore ,the trunk QoSisfinished,suchas RSVP[1]and DiffServ[2].In order to complete theend-to-end QoS,the mechanism of entrance QoS (thebandwidth controller) is introduced. As Fig.1 shows ,if the bandwidth controller circledby the dashed frame is not used,the Ethernet is con-nected with the router directly through 100 Mbit/sbandwidth. Then this router is connect…     

Efficient slice‐aware H.264/AVC video transmission over time‐driven priority networks

This paper proposes a multimedia streaming architecture that combines network and video technologies to handle video traffic over multi‐hop access networks. In this context, resource overprovision typical of current quality of service approaches will become a limiting factor because of the increasing spread of bandwidth‐intensive multimedia applications. The proposed scheme adopts a time‐driven priority scheduling at network nodes and exploits slice classification at the video encoder to differentiate packets. The service guarantees offered by time‐driven priority, together with the packet classification, significantly reduce congestion and increase the video quality at the receiver with respect to the traditional differentiated services (DiffServ) approach, also achieving high resource utilization. This is an important result, as current DiffServ‐based architectures are far from obtaining such resource utilization in conjunction with reasonable delays and jitters. Copyright © 2013 John Wiley & Sons, Ltd.     

基于 WCDMA的移动多媒体解决方案

3G系统的一个主要目的,就是在移动通信领域提供丰富的多媒体应用。为此各种3G标准均仔细研究并提供了相应的解决方案。文章简要介绍了3G系统的数据承载业务及多媒体应用两个方面的内容。     

多媒体调度系统在电力网中的应用

针对电力调度通信视频业务目前的发展状况,介绍了一种多媒体调度系统的方案。阐述了如何利用智能数字调度系统和视频通信系统的结合,为电力调度通信提供了常规语音调度基础之上的视频业务。重点介绍了通过对智能接口的设计、基于视频会议系统中点对点通话、多方会议系统以及基于监控系统的方案实现,达到了多媒体调度系统在电力通信网中的应用。