云存储环境下基于HDFS的海量小文件装箱算法

基于HDFS的云存储系统在当前得到了广泛的应用,然而它存在小文件存储效率不理想的问题。针对该问题,提出了一种基于HDFS的海量小文件装箱算法TPSF。该算法综合考虑上传文件的大小和缓存时间两个指标,设计了基于动态权值的装箱策略。原型实现和性能评价表明,TPSF算法是可行和有效的,能够显著降低HDFS名称节点和数据节点的存储开销。     

广电媒体云存储的数据迁移方案与应用

媒体云存储是广电素材媒资库的核心设备,其为电视节目的制作及存储提供了物理支持.目前,在媒体融合及县级融媒体技术中心的持续推进下,单集群存储的容量急剧下降.本文利用灾备技术和灾备策略提出采用双集群基于存储的远程复制功能来解决单集群容量不断下降的难题,应用结果表明,该方案完全可以解决存储集群不通过节点扩容而采用迁移的方式进...     

厦门广电集团媒体资产管理系统建设策略

厦门广电集团媒体资产管理系统的设计目标包括节目交换及发布平台．资料存储管理中心、全台网基础平台的规划和建设,本文对广电媒体资产管理系统进行了简要概述．介绍了媒体资产管理系统的建设意义,并分析了厦门广电媒体资产管理系统建设策略。     

基于分类概念格的动态策略存取模型

分析了策略系统存储模型在判断策略问条件变量值的相交性方面存在的不足,研究了概念格结构在该方面的优势,提出了基于分类概念格的动态策略存取模型,利用策略属性值之间的偏序关系,将动态策略仓库组织为概念格.设计了基于概念格的策略冲突检测算法,用超概念一子概念查找操作代替属性值相交性判断,缩减了冲突检测空间,提高了冲突检测效率.分析了算法的性能,通过仿真验证了算法的有效性.     

基于IP存储区域网络架构的部队综合媒体信息系统设计与实现

介绍了基于IP存储区域网络架构的部队综合媒体信息系统的设计,该系统实现了装备信息系统与媒体信息系统的集成整合,利用现有存储结构对海量数据进行了数据存储与共享,对目前信息管理系统建设有一定的借鉴意义。     

门限Byzantine quorum系统及其在 分布式存储中的应用

针对纠删编码和门限方案在分布式存储中的应用,提出门限Byzantine quorum系统(TBQS)的概念.该系统与数据分离算法相结合,可以构造可靠性较强的存储系统,当故障服务器个数不超过服务器总数的1/4时,利用TBQS设计存储策略可以实现容错和无间断服务.讨论了TBQS的存在性,构造了两类TBQS并对其效率进行分析,在此基础上设计了基于TBQS的分布式读写协议.     

高校媒体资产管理系统关键技术的研究与实现

存储和检索是高校媒体资产管理系统的关键技术。重点研究与实现了存储中的基于SAN存储架构、迁移策略和检索中的镜头切换检测提取关键帧等关键技术。     

基于CP-ABE算法的电力监控数据访问控制系统

目前设计的电力监控数据访问控制系统控制耗时过长,导致控制过程十分复杂.为了解决上述问题,基于CP-ABE算法设计了一种新的电力监控数据访问控制系统.系统硬件主要由高速缓冲存储器、MicroBlaze软核处理器、以太网媒体访问控制器、中断控制器4部分组成.利用CP-ABE算法设计了数据存储程序和数据访问程序.实验结果表明...     

UIO序列优化搜索算法的研究

UIO序列是对有限状态机进行功能测试的有效手段,在VLSI、通信协议等时序系统中有很强的实际应用背景.本文基于可区分状态组这一概念设计了一个搜索算法,进一步利用搜索信息建立了一个基于"小于"关系的启发策略,有效的剪枝策略的设计将尽可能消除没有意义的搜索分枝,新设计出的多路OPEN/CLOSED表存储机制也加快了相关的判别、处理过程.根据实验结果,分析了优化措施对于改进了搜索过程、减少搜索信息的产生、提高搜索速度有显著的贡献.该算法与以往的算法相比,在时间复杂度和空间复杂度两方面都得到了很大改进.     

浅析电视台数据存储关键技术及应用

目前各电视台都在进行数字化、网络化改造,对媒体资产管理技术应用也达到了前所未有的深度和广度。对于电视台的媒体资产管理,如何选择存储技术和存储策略又成为关键。     

多主多从Stackelberg博弈下的边缘缓存资源分配算法

为鼓励视频服务提供商参与到缓存过程中,本文提出一种基于Stackelberg博弈的激励缓存资源分配算法。与传统激励缓存资源分配方案不同,本文考虑同时存在多个网络运营商和多个视频服务提供商,视频服务提供商从网络运营商处购买存储空间以缓存热门视频。针对该场景,本文将该激励缓存模型建模为多主多从Stackelberg博弈问题,分别构建主方和从方的效用函数,证明了在网络运营商价格确定的情况下,视频服务提供商之间的非合作博弈存在纳什均衡。文章利用分布式迭代算法对该博弈模型进行求解,获得了视频服务提供商的最优缓存策略和网络运营商的最优价格策略。仿真结果表明,本文提出的激励缓存机制可使视频服务提供商获得比其他缓存分配算法更高的单位成本收益。      

Underwater video dehazing based on spatial–temporal information fusion

In this paper, a novel multidimensional underwater video dehazing method is presented to restore and enhance the underwater degraded videos. Videos in the underwater suffer from medium scattering and light absorption. The absorption of light traveling in the water makes the underwater hazing videos different from the atmosphere hazing videos. In order to dehaze the underwater videos, a spatial–temporal information fusion method is proposed which includes two main parts. One is transmission estimation, which is based on the correlation between the adjacent frames of videos to keep the color consistency, where fast tracking and the least square method are used to reduce the influence of camera and object motions and water flowing. Another part is background light estimation to keep consistent atmospheric light values in a video. Extensive experimental results demonstrate that the proposed algorithm can have superior haze removing and color balancing capabilities.     

Resource assignment in short video accelerator system

Video accelerator is developed for better user experience in video sharing websites such as YouTube.PPLive video accelerator (PPVA),which has the largest number of users in China,is based on peer-to-pe...     

SHIP: Cross-layer mobility management scheme based on Session Initiation Protocol and Host Identity Protocol

In law enforcement applications such as surveillance and forensics, video is often presented as evidence. It is therefore of paramount importance to establish the authenticity and reliability of the video data. This paper presents an intelligent video authentication algorithm which integrates learning based Support Vector Machine classification with Singular Value Decomposition watermarking. During video capture and storage, intrinsic local correlation information is extracted from the frames and embedded in the frames at local levels. Tamper detection and classification is performed using the inherent video information and embedded correlation information. The proposed algorithm is independent of the choice of watermark and does not require any key to store. Further, it is robust to global tampering such as frame addition and removal, local attacks such as object alteration and can differentiate between acceptable operations and malicious tampering. Experiments are performed on an extensive database which contains non-tampered videos and videos with several types of tampering. The results show that the proposed algorithm outperforms existing video authentication algorithms.     

Data Allocation and Dynamic Load Balancing for Distributed Video Storage Server

In this paper, a novel initial videos allocation scheme and a dynamic load balancing strategy are proposed for a distributed video storage server in order to increase the availability and reduce operation cost. The initial allocation scheme determines the allocation of video replicas on the servers to achieve static load balance and to obtain a configuration for efficient dynamic load adjustment. From the simulation results, the proposed load shifting algorithm can reduce up to 50% request fail rate if compared with the same initialization algorithm without load shifting. The proposed initial allocation with load shifting also reduces 25% to 60% request fail rate from the least load first initial allocation scheme with load shifting, 5% to 10% request fail rate and 5% to 25% the number of shifting steps from the DASD dancing method. Moreover, a prototype is implemented on Windows NT to examine the correctness and practicability of the proposed schemes.     

A hybrid delivery strategy for a video-on-demand system with customer reneging behavior

A new delivery strategy is proposed for a video-on-demand system to allocate transmission resources according to the popularity of videos. A video is delivered to customers through one of three channels, namely broadcast, multicast and unicast, depending on whether the video is very hot, hot or cold, respectively. An algorithm is developed to select the appropriate delivery channel for the videos so that not only the overall bandwidth of the system is minimized but also a preset quality of service is provided for each customer. An analytical model is also developed to evaluate the bandwidth requirement of the whole system with VCR functionality. The result shows that a significant bandwidth reduction can be achieved when using our proposed delivery strategy.     

A Novel Dynamic and Scalable Caching Algorithm of Proxy Server for Multimedia Objects

This paper presents a novel dynamic and scalable caching algorithm of proxy server with a finite storage size for multimedia objects. Among the multimedia such as text, image, audio and video, video is a dominant component in terms of the performance of proxy server due to its traffic characteristics. For the fast caching process, caching sequences for videos are obtained to decrease both the buffer size and the required bandwidth and saved into metafiles in advance. Then, we present a novel caching and replacing algorithms for multimedia objects based on the metafiles. Finally, experimental results are provided to show the superior performance of the proposed algorithm.     

运动目标检测与特征提取算法的多层次并行优化

针对监控视频中运动目标实时特征提取的需求,在目标检测与特征提取串行算法的基础上,提出了基于OpenMP和多核CPU平台的三层并行优化算法。首先,在算法顶层,将串行算法抽象为两个模块组成的流水线,提出了流水线并行优化算法和相应的缓存管理策略;接着,在算法中层,考虑到特征提取模块中各子模块的功能独立性,设计了功能划分并行优化算法;最后,在算法底层,利用纹理特征提取模块的数据独立性,提出了数据划分并行优化算法。实验结果表明,该三层双模块并行优化算法在四核CPU平台上获得了接近Amdahl极限的加速比,基本实现了实际监控视频中运动目标检测与特征提取的实时处理。该多层次多模块并行优化方法普遍适用于串行算法在多核平台上进行并行优化的分析。     

基于DCT系数统计特性的HEVC视频双压缩检测算法

功能强大和使用简易的视频编辑软件可能会使数字视频遭受到各种不同形式的篡改,视频的真实性和完整性无法得到保证。双压缩是视频篡改的必要条件,双压缩检测则是视频取证的重要辅助手段。通过分析压缩过程中由量化误差引起的离散余弦变换(DCT)系数变化,提出了一种不同量化参数下的高效视频编码(HEVC)视频双压缩检测算法,利用DCT系数直方图和相邻DCT系数对奇偶组合统计特性构造22维联合特征集,最后将特征集用支持向量机(SVM)进行分类识别。实验结果证明了本文算法的有效性。