突发业务流的TES建模方法

高速通信网络存在大量诸如可变速率(VBR)视频这类具有突发性的业务流。突发性,在数学上主要通过业务流的到达时间间隔的边缘概率分布和自相关函数来描述。TES(Transform-Expand-Sample)是一种建模静态随机过程的非参数化技术,能准确匹配边缘概率分布并很好地近似自相关函数。本文简要介绍了TES方法的基本原理,再详细讨论突发业务流的TES建模及其软件实现。对MPEG视频业务的建模的仿真结果表明,TES模型能够很好地表征网络业务流的突发性。     

做好监测工作,提高播出质量

对有线电视系统的技术监督是监测站的一项重要工作，监测工作应准确及时地反映有线电视节目的播出、传输和接收的质量效果。搞好有线电视监测工作对提高有线电视宣传效果、提高有线电视网络维护管理水平、确可安全优质播出将起到重要作用。     

基于Hi3515的水平四画面录像机录像功能的实现

简要介绍了海思Hi3515的硬件特性,着重阐述了该录像机录像功能的软件实现。介绍了录像机软件的总体结构;对音频编码、视频编码和AVI封装的实现原理和方法做了细致地分析研究,给出了相关流程图及水平四画面录像的实现方法;将程序放到开发板上进行了测试。测试结果表明,该录像机可以实现四画面的单独录像和组合录像,录像文件可以直接播放,录像质量和效果良好。可以长时间运行,运行稳定性较好,满足项目的要求。     

基于数字视频的微细作业系统立体成像方案

分析了现有模拟分时立体成像系统的原理和存在闪烁问题的原因,由于两路CCD信号分时显示使帧频下降,图像存在一定的闪烁感,提出了一种改进的立体成像方案,该方案基于数字视频处理,采用高速的视频解码芯片和DSP芯片,提高了图像显示帧频达到无闪烁立体成像的目的,而且利用插场算法提高了图像的清晰度,有利于对进一步实现视觉跟踪控制或利用视觉信息进行自动控制。     

基于内容视频信息检索系统的分析研究

介绍了基于内容视频检索系统所涉及的主要技术和工作原理,对目前国外几个典型视频检索系统进行了分析,指出了存在的问题及相关的解决方案,并就今后如何进行基于内容视频检索系统的研究提出了一些新的看法.     

Robust spatio-temporal error concealment for packet- lossy H.264 video transmission

1 Introduction With the ubiquitous use of Internet and the deployment of next generation of networks, video communications are increa- singly becoming the major services in demand. Unlike data transmission, video communication is essentially time-sensitiv…     

Power and Speed-Efficient Code Transformation of Video Compression Algorithms for RISC Processors

Upcoming multi-media compression applications will require high memory bandwidth. In this paper, we estimate that a software reference implementation of an MPEG-4 video decoder typically requires 200 Mtransfers/s to memory to decode 1 CIF (352×288) Video Object Plane (VOP) at 30 frames/s. This imposes a high penalty in terms of power but also performance.However, we also show that we can heavily improve on the memory transfers, without sacrificing speed (even gaining about 10% on cache misses and cycles for a DEC Alpha), by aggressive code transformations. For this purpose, we have manually applied an extended version of our data transfer and storage exploration (DTSE) methodology, which was originally developed for custom hardware implementations.     

VBR Video Source Characterization and a Practical Hierarchical Model

There are many ways to build up traffic models for VBR video sources. A frequently applied methodology is to use mathematical analysis based on realistic assumptions to set up a source model that generates traffic according to a stochastic process. In this case, the critical issue is the validation of the synthetic trace by comparing statistics to results obtained from measurements on the real source. In this paper, we choose a different and more practical approach to model the behavior of the real traffic source. Our model building philosophy is that we analyze and understand what happens with the video information on its way from the ingress to the multimedia terminal to the egress of the network card. Throughout this journey the information is processed by several mechanisms and we build an empirical model step by step based on our measurement-based observations. Besides understanding the traffic generation procedure, statistical analysis of VBR traffic traces captured from a number of video sequences was also carried out in several scenarios. Using the knowledge of encoding, encapsulation and scheduling processes and results of the trace analysis, a hierarchical source model is set up for modeling the multimedia terminal. Thereby our model imitates the generation of video frames and the inner working of each level of protocol hierarchy and tries to reproduce the complex behavior of the real source. We use the leaky bucket analysis for verification of the model in order to capture directly the behavior of the traffic in a queue.     

智能视频监控技术在哨位安全威胁智能识别中的应用

针对以人工为主的传统监控系统的缺点,对智能视频监控技术在哨位安全威胁智能识别中的应用进行研究。介绍智能监控技术及发展趋势,分析智能分析技术在哨位安全监控预警中的作用。结合目前哨位安全面临的复杂形势和现有安全监控报警手段之间的差异,提出典型应用场景的哨位安全威胁智能识别系统解决方案,阐述了其系统架构、关键设备和关键技术。该研究可为哨位开展安全防护工作提供参考。     

面向网格的视频会议与视频监控体系

分析了设计面向网格的视频会议与视频监控体系的意义,提出设计和实现一个面向网格技术的、资源利用率高、低成本、资源共享、互连互通、相互协作、适应新一代视频会议和视频通信产业链结构和运营模式的视频会议和视频监控体系,研究该体系的架构设计、技术和业务两个层面上若干关键问题、应用场景和研究方法,最后介绍系统实现时采用的GT编程技术。