Efficient transmission of stored video for improved management of network bandwidth

Emerging applications that use stored video complicate the management of network resources due to the bit rate variability of the video. This paper develops a new, more efficient and less complex algorithm for transmission of stored video. Copyright © 2000 John Wiley & Sons, Ltd.     

基于多点通讯服务的视频点播系统

介绍了一种基于多点通讯服务（MCS）的视频点播系统（以下简称MVOD）的设计与实现技术。系统采用VOD服务器和点播用户集成在同一个功能单元的新方式,支持通道管理、视频数据管理、连接管理、点播服务、播放服务、用户接入管理等多种功能。该系统能够运行在Internet网上,具有强的管理能力和很好的扩展性能。     

浅谈视频会议的风险管控

本文首先概述了视频会议风险的种类与影响级别,其次介绍了视频会议风险管控流程,最后探讨了视频会议相关工作中的风险管控内容,为读者做好视频会议技术保障工作提供了参考.     

视频示教系统设计与应用

针对视频监控系统应用、交互式教学管理、实验课程互动与管理、即时课件的制作,提出一种实用的简单的视频示教系统,该系统综合考虑学校的实际使用以及对现有实验资源的整合和后期系统的扩展,在软硬件建设上都能保持可持续发展和前瞻性,以信息展示为切入点将实验教学中的视频示教、视频监控、门禁管理贯串起来,建立一个基于智能实验室管理模式下实验实训教学辅助管理系统,以实现数字化校园管理的目的。     

基于IMS技术的三网融合网络多媒体业务部署

提出了基于云计算架构的三网融合网络多媒体视频业务部署技术,解决了三网融合网络海量终端用户访问及多媒体业务及用户的管理等问题.给出了三网融合网络的多媒体视频业务管理模型,并且详细说明了多媒体视频应用服务器及客户端的功能模块,以实例方式说明了QoS策略决策过程.为三网融合网络多媒体业务部署提供了指导性的技术方案.     

数字CCTV系统在高速公路上的运用

介绍了数字视频监控系统在高速公路应用的多种功能,主要阐述了其技术的应用如管理功能、联动功能、视频管理、互联网远程管理、图像显示的质量以及设备参数等。     

Semantic video fingerprinting and retrieval using face information

The management of large video databases, especially those containing motion picture and television data, is a major contemporary challenge. A very significant tool for this management is the ability to retrieve those segments that are perceptually similar to a query segment. Another similar but equally important task is determining if a query segment is a (possibly modified) copy of part of a video in the database. The basic way to perform these two tasks is to characterize each video segment with a unique representation called a signature. Using semantic information for the construction of the signatures is a good way to ensure robustness in retrieval and fingerprinting. Here a ubiquitous semantic feature, namely the existence and identity of human faces, will be used to construct the signature. A fast algorithm has been developed to quickly and robustly perform these two tasks on very large video databases. The prerequisite face recognition was performed by a commercial system. Having verified the basic efficacy of our algorithm on a database of real video from motion pictures and television series, we then proceed to further explore its performance in an artificial digital video database, which was created using a probabilistic model of the video creation process. This enabled us to explore variations in performance based on parameters that were impossible to control in a real video database. Furthermore, the suitability of the proposed approach for very large databases was tested using (artificial) data corresponding to hundreds or thousands of hours of video.     

H.264视频编码的嵌入式系统实现

H.264是ITU-T组织针对实时视频通讯应用制定的新一代视频压缩标准,开发H.264的嵌入式视频系统有重要的意义.该文在深入研究H.264标准和嵌入式系统的基础上,设计了一种以TI公司的TMS320C6416DSP为核心处理器的嵌入式视频编码系统,系统主要包括视频解码,视频转换,采集视频缓冲区管理,编码及码流输出等.对于系统实现中所涉及的视频转换,内存管理机制,代码优化等进行了详细的讨论.     

基于DM642的视频图像实时通信和传输

文中以DM642为核心处理器,设计了相应的视频采集电路和视频输出端口电路,其中视频采集电路的主要芯片是TVP5150A。视频输出端口电路的主要芯片是SAA7105。论文还给出了系统的软件设计思想以及实际的实现过程：应用DSP／BIOS实时操作系统对系统资源进行初始化和控制,确定系统工作方式,完成任务的调度管理、中断服务管理和外设驱动程序的管理等操作。DM642成功地实现了视频图像的采集处理和传输。     

城市视频监控系统解决方案

主要介绍了城市视频监控系统的组成,具体包括视频监控管理平台子系统、传输网络子系统、前端监控点子系统、监控中心子系统、无线传输子系统、可视化指挥子系统、安全平台子系统、运维管理子系统以及供电子系统等。设计力求通过此系统,充分利用视频技术和互联网技术,全面提升城市管理水平。     

Hierarchical storage management in a distributed VOD system

The article describes the storage management algorithms in the Berkeley Video-on-Demand System, a hierarchical storage management system designed to support transparent access to thousands of hours of video material. Storage management algorithms handle continuous media objects stored on video servers within a hierarchical distributed video-on-demand system. Media objects stored permanently on tertiary storage devices are moved to video servers when needed. Algorithms manage the distributed cache in the video servers and select a video server on which to place a requested object. The object-placement algorithm uses server load, network load, and service-wait times to optimize system performance     

Resource management for video streaming in ad hoc networks

Video streaming over wireless links is a challenging issue due to the stringent Quality-of-Service (QoS) requirements of video traffic, the limited wireless channel bandwidth and the broadcast nature of wireless medium. As contention-based or reservation-based (i.e., contention-free) medium access control (MAC) protocols in existing wireless link-layer standards cannot efficiently support multimedia applications such as video streaming, a hybrid approach has been proposed, which uses both contention and reservation-based channel access mechanisms to transmit packets for each video source. Using this content-aware resource management approach, each video source reserves well below its peak data rate, and uses contention-based media access to transmit the remainder of the packets. In this paper, we first propose two conflict avoidance strategies and two buffering architectures for video streaming over ad hoc networks. Considering the interactions of reservation and contention, we develop the analytical model for the saturated traffic case and then extend it to derive tight performance bounds for the unsaturated case. Using the MAC protocols specified in the WiMedia ECMA-368 standard as an example, extensive simulations have been conducted to validate the analysis. Real video traces have been used to examine the video streaming performance. The analytical and simulation results demonstrate the effectiveness and efficiency of the hybrid resource management approach, and also reveal the impact of the conflict avoidance strategy and buffering design on the video performance.     

Application-aware buffer management: new metrics and techniques

An important issue for video transmission over IP networks is preservation of perceived video quality despite packet loss. Packet loss can be detrimental to compressed video. However, reducing packet loss to a very low level is difficult with current loss control techniques. Furthermore, even a very low objective loss probability can still seriously distort perceived video quality. This paper presents two buffer management schemes using video characteristics. They increase maximum loss tolerance for a desired level of video quality, providing better quality at equal loss ratios, when compared to a conventional buffer management scheme. Meanwhile, service fairness and network efficiency are also improved.     

融合媒体下视频内容关联聚合的研究

融合媒体时代,媒体信息的传播形式发生了巨大转变,对海量、异构的媒体内容的管理和利用日益重要,需要深入挖掘媒体内容的关联性。本文分析和介绍了融合媒体下视频内容关联的必要性和相关技术,针对视频内容的关联展开研究。一方面,建立视频深层次信息,如视频语义信息库;另一方面,对媒体元数据规范的扩展。提出了一种视频内容关联与用户数据聚合的服务平台,有助于提供给用户电视互动的创新业务模式。     

基于3G传输的视频监控系统的后台设计

设计了一种基于3G网络传输的移动视频监控系统的后端管理服务平台(后台);结合视频监控系统总体设计框架,对后台的设计方案及RTP解封、AES解密、音视频解码、音视频配置及USB管理等各功能模块设计和实现方法作了详细介绍.经测试,该平台工作稳定,在视频监控领域应用良好.     

Software architecture for integration of video services in theEtherphone system

Software mechanisms that make use of analog transmission and storage of video for computer-controlled video communication and file storage are described. The authors extended the Etherphone voice management system to support video conferencing and file storage. The software mechanisms for conference management consist of a central connection manager, and video and user interface agents running on client workstations. A conferencing architecture that supports multiplicity in the number of conferences and media is presented. The video file server stores and retrieves full-motion video information within conferences. It uses optical disks to store video frames and builds a high-level file and directory interface. The user interface to the directory interface is a multimedia document editor that permits video annotations to be freely interspersed with text. The performance of the system, which spans multiple media networks, has been highly satisfactory     

一种脱机硬盘录像系统的设计

介绍一种脱机硬盘录像系统的设计方法。包括视频压缩部分、视频解压缩部分和硬盘接口管理部分，系统的核心控制是由于一枚TMS320F26实现的。整个系统具有性能稳定、可靠性高、操作方便等优点，成功地满足了高可靠要求的视频监控系统的性能要求。     

移动视频业务质量分析系统的设计与实现

移动视频业务客户感知不仅取决于网络质量,更取决于“端管云台”各环节,亟需从基于网络本身的质量管理向注重客户感知的端到端横向一体化质量保障机制转变.为解决这些问题,介绍一个移动视频业务质量分析系统的设计及其实现.系统以移动视频业务各环节的信令消息为分析数据源;从业务、流向、地域、网元、小区、终端6个维度建立分析模型;呈现视频业务的关键KQI值及变化趋势,常态化开展性能指标监控;从用户视角发现问题,对精细化业务、区域等角度的性能劣化指标进行趋势分析、质差分析、定界分析;对发现的问题进行自动或人工派单处理,建立完备的问题闭环管理机制.该系统能够显著提升移动视频质量管理工作水平,并显著降低工作成本.对系统的架构、主要功能部件的实现进行了详细的介绍,对系统的应用进行了举例说明.     

3G网络视频平台高可用性

分析了3G网络中视频业务平台的高可用性技术的几个关键问题.视频业务是3G网络中的重要应用,不同于传统的广播电视,它更多的是具有电信设备平台的基本特点.根据CPSB硬件平台的特点,讨论了基于该硬件平台的高可用性(HA: High Availability)管理系统需要实现的各种功能,提出了基于此种硬件平台的HA管理系统的结构功能组成和工作原理,并提出了基于该硬件平台的HA管理系统实现中关键技术.