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1.
Multimedia Tools and Applications - Counting-based secret sharing is becoming a vital efficient multimedia technique for raising the security of sensitive data especially when collective access to...  相似文献   

2.
Multimedia Tools and Applications - Watermarking is the process of embedding secret data to prove ownership copyright authentication validation. It is becoming urgently required within e-videos to...  相似文献   

3.
Multimedia Tools and Applications - The secret sharing scheme is a data security tool to provide safe reliability and robustness for multi-user authentication systems. This work focus on expanding...  相似文献   

4.
Multimedia Tools and Applications - Watermarking of multimedia gives more attention to the research society. This paper presents the non-blind watermarking technique on video; initially, a...  相似文献   

5.
Multimedia Tools and Applications - Secret Sharing is required in situations where access to important resources has to be protected by more than one person. We propose new secret-sharing scheme...  相似文献   

6.
This paper describes security and privacy issues for multimedia database management systems. Multimedia data includes text, images, audio and video. It describes access control for multimedia database management systems and describes security policies and security architectures for such systems. Privacy problems that result from multimedia data mining are also discussed.
Bhavani ThuraisinghamEmail:
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7.
超长指令字(VLIW)架构数字信号处理器(DSP)具有强大的处理能力,在该DSP处理器上一方面通过增加专用指令,另一方面通过改进算法,达到了硬件软件全面加速,实现了密码芯片,满足了高清多媒体监控系统的实时加解密和认证等需求.该密码处理芯片首次实现符合安全防范监控数字音视频编码技术标准的可伸缩音视频编码(SVAC[1])码流的安全认证处理,并增加了与音/视频芯片之间的接口,接收音/视频编码流,进行加解密等.密码处理芯片与音/视频芯片共同组成了高清多媒体监控系统.大量的软件和FPGA评估验证保证了数据安全认证的实时性、安全性、正确性.  相似文献   

8.
9.
This paper is derived from a keynote address given that the DMS-03 meeting. It chronicles the need and development of next generation networks (NGN) in the United States. Specific organizational examples are derived from the Internet2-Abilene Network. The technical characteristics of a next generation network versus the Internet are discussed. Examples are given from the point of view of the need for a quality of service based network to deliver distributed multimedia healthcare information to the point of need. The concepts of network trust and of a network based scalable information infrastructure for the reliable delivery of distributed multimedia information is also introduced.
Michael J. AckermanEmail:
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10.
The amount of video content available nowadays makes video abstraction techniques a necessary tool to ease the access to the already huge and ever growing video databases. Nevertheless, many of the existing video abstraction approaches have high computational requirements, complicating the integration and exploitation of current technologies in real environments. This paper presents a novel method for news bulletin abstraction which combines on-line story segmentation, on-line video skimming and layout composition techniques. The developed algorithm provides an efficient, automatic and on-line news abstraction method which takes advantage of the specific characteristics of news bulletins for obtaining representative news abstracts.  相似文献   

11.
Automating the generation of coordinated multimedia explanations   总被引:1,自引:0,他引:1  
Feiner  S.K. McKeown  K.R. 《Computer》1991,24(10):33-41
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12.
Jian Zhang  S. C. Cheung 《Software》2002,32(15):1411-1435
With the advancement in network bandwidth and computing power, multimedia systems have become a popular means for information delivery. However, general principles of system testing cannot be directly applied to testing of multimedia systems on account of their stringent temporal and synchronization requirements. In particular, few studies have been made on the stress testing of multimedia systems with respect to their temporal requirements under resource saturation. Stress testing is important because erroneous behavior is most likely to occur under resource saturation. This paper presents an automatable method of test case generation for the stress testing of multimedia systems. It adapts constraint solving techniques to generate test cases that lead to potential resource saturation in a multimedia system. Coverage of the test cases is defined upon the reachability graph of a multimedia system. The proposed stress testing technique is supported by tools and has been successfully applied to a real‐life commercial multimedia system. Although our technique focuses on the stress testing of multimedia systems, the underlying issues and concepts are applicable to other types of real‐time systems. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

13.
为了解决显示屏亮度不统一所引起的多媒体网页图像色彩退化的问题,设计一种基于RGB模式的图像色彩增强模型。根据RGB模式的要求,对视觉图像从照度和反射两个分量的角度进行光滑化处理,在此基础上,利用RGB格式的增强系数,建立视觉图像的色彩增强函数。通过增强多媒体网页中视觉图像的整体亮度、调整图像局部对比度,恢复图像色彩的方式,增强视觉图像的色彩。在Windows XP系统内进行图像色彩增强效果的检测,结果显示,基于RGB模式的色彩增强模型能够切实增强图像的亮度、信息熵、饱和度。说明该模型具备有效性,较传统的直方图均衡模型的图像色彩增强效果好,符合实际推广应用标准。  相似文献   

14.
The thermal band of the Airborne Thematic Mapper (ATM) has the same spatial resolution as that of the reflective spectral bands and therefore can be used together with other bands without degrading the resolution as happens with Landsat TM. Here we show that the total solar irradiance on the land surface can be simulated by a properly weighted summation of the thermal band and all the reflective spectral bands. The simulated reflectance as well as emittance can then be derived from the relation between irradiance, thermal emittance, spectral reflectance and albedo based on a simplified energy conservation model of solar radiation incident on a land surface. Compared with other methods for spectral enhancement and topography suppression, such as ratio and logarithmic residual, this method has the advantage of conserving surface albedo information and thus produces a reasonable simulation of reflectance.  相似文献   

15.
This paper introduces a secure speech communication approach, which is based on encryption and authentication. This system is based on Advanced Encryption Standard (AES) for encryption and private image database for enhancement of encryption and for authentication. The idea of this cryptosystem is based on XOR of one image from image database with the clear speech before encryption and embedding the index number of this image in the database as a least significant bit watermark into speech. A comparison study is held between the AES block cipher algorithm and the proposed algorithm. This proposed cryptosystem used to enhance the security of AES algorithm and increase its immunity to brute force attacks. It used also to provide authentication and enhance security by addition of extra key which don’t need to be exchanged between parts depending on the embedded image. The extra proposed step remove residual intelligibility from clear speech and fill the silent periods within speech conversation and help in destroy format and pitch information. Security analyses are presented for the proposed cryptosystem from a strict cryptographic viewpoint. Experimental results verify and prove that the proposed cryptosystem is highly secure from the cryptographic viewpoint.  相似文献   

16.
Digital watermarking techniques have been proposed as a solution to the problem of copyright protection of multimedia data. In this paper, we propose a novel Chinese remainder theorem (CRT)-based technique for digital watermarking. The use of CRT for this purpose provides additional security along with resistance to some familiar attacks. We have shown that this technique is quite resilient to addition of the noise. We have compared performance of the proposed technique with recently reported two singular value decomposition (SVD)-based watermarking techniques and shown its superior performance in terms of tampering assessment function (TAF), computational efficiency and peak signal to noise ratio (PSNR). For example, the embedding time of the proposed CRT-based scheme is 6 and 3 times faster than the SVD-based Schemes 1 and 2, respectively. This technique can also be applied to document, audio and video contents.  相似文献   

17.
《Computer Networks》2000,32(2):185-209
This paper presents a Differentiated Services (Diffserv or DS) architecture for multimedia streaming applications. Specifically, we define two types of services in the context of Assured Forwarding (AF) per hop behavior (PHB) that are differentiated in terms of reliability of packet delivery: the High Reliable (HR) service and the Less Assured (LA) service. We propose a novel node mechanism called Selective Pushout with Random Early Detection (SPRED) that is capable of simultaneously achieving the following four objectives: (1) a core router does not maintain any state information for each flow (i.e., core-stateless); (2) the packet sequence within each flow is not re-ordered at a node; (3) packets from HR service are delivered more reliably than packets from LA service at a node during congestion; and (4) packets from TCP traffic are dropped randomly to avoid global synchronization during congestion. We show that SPRED is a generalized buffer management algorithm of both tail-dropping and Random Early Detection (RED), and combines the best features of pushout (PO), RED and RED with In/Out (RIO) mechanisms. Simulation results demonstrate that under the same link speed and network topology, network nodes employing our Diffserv architecture have substantial performance improvement over the current Best Effort (BE) Internet architecture for multimedia streaming applications.  相似文献   

18.
Variable bit rate (VBR) compression for media streams allocates more bits to complex scenes and fewer bits to simple scenes. This results in a higher and more uniform visual and aural quality. The disadvantage of the VBR technique is that it results in bursty network traffic and uneven resource utilization when streaming media. In this study we propose an online media transmission smoothing technique that requires no a priori knowledge of the actual bit rate. It utilizes multi-level buffer thresholds at the client side that trigger feedback information sent to the server. This technique can be applied to both live captured streams and stored streams without requiring any server side pre-processing. We have implemented this scheme in our continuous media server and verified its operation across real world LAN and WAN connections. The results show smoother transmission schedules than any other previously proposed online technique. This research has been funded in part by NSF grants EEC-9529152 (IMSC ERC), and IIS-0082826, DARPA and USAF under agreement nr. F30602-99-1-0524, and unrestricted cash/equipment gifts from NCR, IBM, Intel and SUN. Roger Zimmermann is currently a Research Assistant Professor with the Computer Science Department and a Research Area Director with the Integrated Media Systems Center (IMSC) at the University of Southern California. His research activities focus on streaming media architectures, peer-to-peer systems, immersive environments, and multimodal databases. He has made significant contributions in the areas of interactive and high quality video streaming, collaborative large-scale group communications, and mobile location-based services. Dr. Zimmermann has co-authored a book, a patent and more than seventy conference publications, journal articles and book chapters in the areas of multimedia and databases. He was the co-chair of the ACM NRBC 2004 workshop, the Open Source Software Competition of the ACM Multimedia 2004 conference, the short paper program systems track of ACM Multimedia 2005 and will be the proceedings chair of ACM Multimedia 2006. He is on the editorial board of SIGMOD DiSC, the ACM Computers in Entertainment magazine and the International Journal of Multimedia Tools and Applications. He has served on many conference program committees such as ACM Multimedia, SPIE MMCN and IEEE ICME. Cyrus Shahabi is currently an Associate Professor and the Director of the Information Laboratory (InfoLAB) at the Computer Science Department and also a Research Area Director at the NSF's Integrated Media Systems Center (IMSC) at the University of Southern California. He received his M.S. and Ph.D. degrees in Computer Science from the University of Southern California in May 1993 and August 1996, respectively. His B.S. degree is in Computer Engineering from Sharif University of Technology, Iran. He has two books and more than hundred articles, book chapters, and conference papers in the areas of databases and multimedia. Dr. Shahabi's current research interests include Peer-to-Peer Systems, Streaming Architectures, Geospatial Data Integration and Multidimensional Data Analysis. He is currently an associate editor of the IEEE Transactions on Parallel and Distributed Systems (TPDS) and on the editorial board of ACM Computers in Entertainment magazine. He is also the program committee chair of ICDE NetDB 2005 and ACM GIS 2005. He serves on many conference program committees such as IEEE ICDE 2006, ACM CIKM 2005, SSTD 2005 and ACM SIGMOD 2004. Dr. Shahabi is the recipient of the 2002 National Science Foundation CAREER Award and 2003 Presidential Early Career Awards for Scientists and Engineers (PECASE). In 2001, he also received an award from the Okawa Foundations. Kun Fu is currently a Ph.D candidate in computer science from the University of Southern California. He did research at the Data Communication Technology Research Institute and National Data Communication Engineering Center in China prior to coming to the United States and is currently working on large scale data stream recording architectures at the NSF's Integrated Media System Center (IMSC) and Data Management Research Laboratory (DMRL) at the Computer Science Department at USC. He received an MS in engineering science from the University of Toledo. He is a member of the IEEE. His research interests are in the area of scalable streaming architectures, distributed real-time systems, and multimedia computing and networking. Mehrdad Jahangiri was born in Tehran, Iran. He received the B.S. degree in Civil Engineering from University of Tehran at Tehran, in 1999. He is currently working towards the Ph.D. degree in Computer Science at the University of Southern California. He is currently a research assistant working on multidimensional data analysis at Integrated Media Systems Center (IMSC)—Information Laboratory (InfoLAB) at the Computer Science Department of the University of Southern California.  相似文献   

19.
An electronic voting system makes it possible for the voters to cast their ballots over the computer network. Hence, voters can participate in elections without having to go to the polling places, which is more convenient and efficient. To design a practical voting scheme, Mu and Varadharajan have recently proposed an anonymous secure electronic voting scheme to be applied over the network. It does not only protect voters' privacy and prevent double voting, but also suits large-scale elections. However, the scheme has a weakness in security; that is, some voters may still double vote without being detected and may even reveal information they should not. In this paper, we shall show this weakness and improve the scheme to increase the protection against fraudulence.  相似文献   

20.
The IP Multimedia Subsystem (IMS) is defined by the 3 rd Generation Partnership Project (3GPP) as a new core network domain. IMS provides a service control platform that allows creation of new multimedia and multi-session applications utilizing wireless and wireline transport capabilities. In this paper we will cover the concepts and standards defining IMS and review the network architecture from a mobile perspective. We will see how IMS interacts with the Packet Switched Domain (e.g. Wireless LAN, GPRS, and UMTS networks), the Internet, and application services. Then we will examine the key IMS capabilities and show how they can be combined to create new mobile IP services. Finally, we present a software architecture, which is enabled by IMS and allows development of unique applications (with multimedia/multi-session functionality, single/multi-user, service to user). The software architecture is illustrated by an example of a prototype application. This work was done when the author was with Siemens Communications Inc., Boca Raton, FL  相似文献   

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