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Optical Bit-Plane-Based 3D-JST Cryptography Algorithm With Cascaded 2D-FrFT Encryption for Efficient and Secure HEVC Communication

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IEEE access 2021年 9卷 35004-35026页

作者： El-Shafai, Walid Almomani, Iman M. Alkhayer, Aala Prince Sultan Univ Comp Sci Dept Secur Engn Lab Riyadh 11586 Saudi Arabia Menou Univ Fac Elect Engn Dept Elect & Elect Commun Engn Menoufia 32952 Egypt Univ Jordan King Abdullah II Sch Informat Technol Comp Sci Dept Amman 11942 Jordan

The rapid growth of multimedia communication systems has expanded the High-Efficiency Video Coding (HEVC) security applications precipitously. Therefore, there is an urgent, elevated need to protect and secure the HEVC content during streaming and communication over insecure channels to ensure the privacy of HEVC data against intruders and attackers. This paper introduces an optical HEVC cipher algorithm based on bit-plane 3D-JST (Three-Dimensional Jigsaw Transform) and multistage 2D-FrFT (Two-Dimensional Fractional Fourier Transform) encryption. The main advantage of employing 3D-JST is its unitary transform that has an inverse transform used to reorganize the HEVC frame-blocks in an indiscriminately way. The proposed algorithm embraces the cascaded 2D-FrFT encryption in the optical domain using a single arbitrary phase code;to be executed all optically with a lone lens. The suggested algorithm utilizes the two 2D-FrFT stages with distinct kernels in mutually dimensions separated by employing the arbitrary phase code. A foregoing bit-plane permutation stage is conducted on the input HEVC frames before the 3D-JST and 2D-FrFT processes to accomplish a high robustness and security level. To validate the efficacy of the proposed cryptography algorithm for secure HEVC streaming, a comprehensive evaluation framework has been introduced and followed to (a) test HEVC streams against different statistical cryptographic metrics, (b) compare the proposed algorithm with recent related works whether optical-based or digital-based algorithms and (c) study the impact of different security attacks on its performance. The evaluation results show a secure and efficient proposed cryptography algorithm that outperforms the conventional and related cryptography algorithms in terms of all examined evaluation metrics.

关键词： Encryption Streaming media Cryptography Security Two dimensional displays Optical network units Optical imaging Optical encryption HEVC communication 3D-JST 2D-FrFT cryptography multimedia applications video coding security efficiency diffusion attack histogram

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content-based retrieval in multimedia databases based on feature models 1st

Content-based retrieval in multimedia databases based on fea...

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1st International Conference on Advanced multimedia content Processing (AMCP 98)

作者： Apers, P Kersten, M Univ Twente NL-7500 AE Enschede Netherlands CWI NL-1009 AB Amsterdam Netherlands

ISBN: (纸本)3540657622

With the increasing popularity of WWW, the main challenge in computer science has become content-based retrieval of multimedia objects. Until now access of multimedia objects in databases was done by means of keywords. Now, with the integration of feature-detection algorithms in database systems software, content-based retrieval can be fully integrated with query processing. In this invited paper, we describe our experimentation platform under development that fully integrates traditional query processing and content-based retrieval and that is based on feature databases, making database technology available to multimedia.

关键词： content based retrieval

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WikiPrints - Rendering Enterprise Wiki content for Printing

WikiPrints - Rendering Enterprise Wiki Content for Printing

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Conference on Imaging and Printing in a Web 2.0 World;and multimedia content access - algorithms and systems IV

作者： Berkner, Kathrin Ricoh Innovat Inc Menlo Pk CA 94025 USA

ISBN: (纸本)9780819479334

Wikis have become a tool of choice for collaborative, informative communication. In contrast to the immense Wikipedia, that serves as a reference web site and typically covers only one topic per web page, enterprise wikis are often used as project management tools and contain several closely related pages authored by members of one project. In that scenario it is useful to print closely related content for review or teaching purposes. In this paper we propose a novel technique for rendering enterprise wiki content for printing called WikiPrints, that creates a linearized version of wiki content formatted as a mixture between web layout and conventional document layout suitable for printing. Compared to existing print options for wiki content, Wikiprints automatically selects content from different wiki pages given user preferences and usage scenarios. Meta data such as content authors or time of content editing are considered. A preview of the linearized content is shown to the user and an interface for making manual formatting changes provided.

关键词： Wiki pagination print formatting content linearization graph model arborescence

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Recent advances in multimedia networking

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multimedia TOOLS AND APPLICATIONS 2011年第3期54卷 635-647页

作者： Cerqueira, Eduardo Zeadally, Sherali Leszczuk, Mikolaj Curado, Marilia Mauthe, Andreas Fed Univ Para BR-66075110 Belem Para Brazil Univ Dist Columbia Washington DC 20008 USA AGH Univ Sci & Technol PL-30059 Krakow Poland Univ Coimbra P-3030290 Coimbra Portugal Univ Lancaster Lancaster LA1 4WA England

In recent years, the ubiquity of multimedia services along with the proliferation of mobile devices and the demand for new audio and video applications are changing the life style of users. User demands for multimedia access anywhere, anytime from any device are creating new challenges for research communities from both academia and industry. It is expected that video-based services alone will account for 50 percent of all consumer network traffic in 2012 and we will continue to witness the explosive growth in users sharing multimedia content over the Internet. In this context, new network, application, and user-based approaches must be created to deal with such complex multimedia systems. This paper presents some of the recent advances in multimedia networking focusing primarily on areas that have been receiving attention recently and are expected to continue to generate further interests in coming years. These areas include Quality of Experience (QoE) and various related standardization issues, content Distribution Networks (CDNs), multimedia communications, mobile multimedia. This paper also briefly highlights some of the major challenges that still need to be addressed to enable the support and delivery of multimedia services anywhere, anytime over highly heterogeneous infrastructures and user terminal devices.

关键词： multimedia Quality of service Quality of experience content distribution Networking Mobile multimedia

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Searching through Photographic Databases with QuickLook

Searching through Photographic Databases with QuickLook

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Conference on multimedia on Mobile Devices and multimedia content access - algorithms and systems VI

作者： Ciocca, Gianluigi Cusano, Claudio Schettini, Raimondo Santini, Simone de Polo, Andrea Tavanti, Francesca Univ Milano Bicocca Viale Sarca 336 I-20126 Milan Italy Univ Autonoma Madrid Madrid 28049 Spain Alinari 24 ORE SpA RD Multimedia Lab I-50123 Florence Italy

ISBN: (纸本)9780819489517

We present here the results obtained by including a new image descriptor, that we called prosemantic feature vector, within the framework of QuickLook(2) image retrieval system. By coupling the prosemantic features and the relevance feedback mechanism provided by QuickLook(2), the user can move in a more rapid and precise way through the feature space toward the intended goal. The prosemantic features are obtained by a two-step feature extraction process. At the first step, low level features related to image structure and color distribution are extracted from the images. At the second step, these features are used as input to a bank of classifiers, each one trained to recognize a given semantic category, to produce score vectors. We evaluated the efficacy of the prosemantic features under search tasks on a dataset provided by Fratelli Alinari Photo Archive.

关键词： Image retrieval image indexing semantic gap prosemantic features

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Overcome the shortcoming in mobile stereoscopy

Overcome the shortcoming in mobile stereoscopy

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Conference on multimedia on Mobile Devices and multimedia content access - algorithms and systems V

作者： Lee, Kwang-Hoon Kim, Sung-Kyu Konkuk Univ Dept Adv Technol Fus Seoul South Korea KIST Imaging Media Res Ctr Seoul South Korea

ISBN: (纸本)9780819484185

The mobile device has the lacked space for configuring cameras to make either ortho- or hyperstereoscopic condition with a small size of display. Therefore mobile stereoscopy cannot provide a presence with a good depth sense to an observer. To solve this problem, we focused on the depth sense control method with a switchable stereo camera alignment. In converging type, the fusible stereo area becomes wider compared to a parallel type when the same focal length was used in both types. This matter makes it that the stereo fusible area formed by converging type to be equal to the parallel type with a more shorten focal length. Therefore there is a kind of the zoom-out effect at the reconstructed depth sense. In diverging type, the fusible stereo area becomes narrower than the parallel. As the same way, the diverging type guarantees a similar characteristic of that an increased focal length is considered in parallel type. Therefore there is a zoom-in effect existing. Stereoscopic zoom-in depth effect becomes rapidly changed by the increased angle but zoom-out becomes retarded relatively.

关键词： Stereoscopic cameras Cameras Sensors Stereoscopy Distributed interactive simulations Image processing Imaging systems Mobile devices Image sensors multimedia

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Using Wi-Fi-Hotspots as an intrusion vector into corporate networks

Using Wi-Fi-Hotspots as an intrusion vector into corporate n...

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Conference on multimedia on Mobile Devices and multimedia content access - algorithms and systems VI

作者： Scharsich, Maximilian Holl, Friedrich L. Univ. of Applied Sciences Brandenburg (Germany)

ISBN: (纸本)9780819489517

The following paper describes a method of gaining access to corporate networks through users who use virtual private networks over a modified Hotspot under the control of an attacker. Over 100,000 Hotspots offer an easy access to the Internet throughout the world. Almost every operator will inform the user though that browsing via a Hotspot is insecure because the connection is unencrypted. Hotspots often offer no typical encryption like WEP, WPA or WPA2;the communication is just send over the air, readable for everyone. This situation is not unknown - the Firesheep-Plugin for Firefox shows this impressive. One possible solution is the usage of a Virtual Private Network (VPN), which enables the user to communicate through a secure tunnel. In this typical business case the company's VPN is used to access internal documents and work with business' applications. All data sent out via a Hotspot using a VPN is encrypted and unreadable for potential attackers. But, what if the Hotspot, the user's connected to, is already under the control of an attacker? Nowadays it's easy to use hardware which extends the range of the Wi-Fi enormously and to set up an own Hotspot (with little expense). If an attacker then copies the login-site of a legit Hotspot and adapts his Hotspot in order to show the same site, he won't just be able to obtain the users credentials, he will also be capable of implementing malware into that site to gain access to the victim's personal device. Now that the attacker has gained access, he can start sniffing around and will possibly find out that a VPN application is being executed. If the attacker finds a proper application, he can start to use the victim's device to access the internal structure of the corporate network;the device now serves as a router for the attacker. Security mechanisms like firewalls and IDS, which are normally used as perimeter protection, won't be able to detect the attacker because he uses legitimate communication tunnels to get

关键词： Internet Control systems Network security Computer security Data communications Java multimedia Applied sciences Imaging systems Mobile devices

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The Task-Dependent Effect of Tags and Ratings on Social Media access

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ACM TRANSACTIONS ON INFORMATION systems 2010年第4期28卷 21.1-21.42页

作者： Clements, Maarten De Vries, Arjen P. Reinders, Marcel J. T. Delft Univ Technol Fac Elect Engn Math & Comp Sci EEMCS NL-2600 AA Delft Netherlands

Recently, online social networks have emerged that allow people to share their multimedia files, retrieve interesting content, and discover like-minded people. These systems often provide the possibility to annotate the content with tags and ratings. Using a random walk through the social annotation graph, we have combined these annotations into a retrieval model that effectively balances the personal preferences and opinions of like-minded users into a single relevance ranking for either content, tags, or people. We use this model to identify the influence of different annotation methods and system design aspects on common ranking tasks in social content systems. Our results show that a combination of rating and tagging information can improve tasks like search and recommendation. The optimal influence of both sources on the ranking is highly dependent on the retrieval task and system design. Results on content search and tag suggestion indicate that the profile created by a user's annotations can be used effectively to adapt the ranking to personal preferences. The random walk reduces sparsity problems by smoothly integrating indirectly related concepts in the relevance ranking, which is especially valuable for cold-start users or individual tagging systems like YouTube and Flickr.

关键词： algorithms Experimentation Human Factors Personalization content retrieval recommendation social media random walk rating tagging librarything movielens

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Building multicast trees for multimedia streaming in heterogeneous P2P networks

Building multicast trees for multimedia streaming in heterog...

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International Conference on systems Communications

作者： Tan, XR Datta, S York Univ Dept Comp Sci & Engn Toronto ON M3J 2R7 Canada

ISBN: (纸本)0769524222

P2P networks have been proposed as a scalable, inexpensive solution to the problem of distributing multimedia content over the Internet. Since real P2P systems exhibit considerable heterogeneity in hardware, software and network connections, the design of P2P streaming networks must factor in this variation. There are two different sources of heterogeneity in P2P networks. Most existing work in the literature handle heterogeneity among receivers and requirements by the use of different multimedia encodings of the same content. In this paper we focus on the problems caused by heterogeneity in the network delays connecting receivers to the sender We assume that there is a single multicast tree and a single video stream. We propose new algorithms for building multicast trees for multimedia streaming in heterogeneous P2P networks. Our algorithms differ in the amount of communication and computational resources they require. We compare the performance (using simulations) of our algorithms with an existing algorithm Zigzag [20, 2 1]. Our results show that two of our algorithms (algorithm FollowTree-Landmark-ii and algorithm FollowTree) significantly outperform Zigzag.

关键词： Multicasting

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Image quality assessment in multimedia applications

Image quality assessment in multimedia applications

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multimedia content access: algorithms and systems iiI

作者： Ciocca, G. Marini, F. Schettini, R. DISCo Dipartimento di Informatica Sistemistica e Comunicazione Universita Degli Studi di Milano-Bicocca Viale Sarca 336 20126 Milano Italy

In the framework of multimedia applications image quality may have different meanings and interpretations. In this paper, considering the quality of an image as the degree of adequacy to its function/goal within a specific application field, we provide an organized overview of image quality assessment methods by putting in evidence their applicability and limitations in different application domains. Three scenarios have been chosen representing three typical applications with different degree of constraints in their image workflow chains and requiring different image quality assessment methodologies. ©2009 SPIE-IS&T.

关键词： Image quality

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