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Efficient frequency domain selective scrambling of digital video

IEEE TRANSACTIONS ON multimedia 2003年第1期5卷 118-129页

作者： Zeng, WJ Lei, SM Amer Inc Sharp Labs Camas WA 98607 USA

multimedia data security is very important for multimedia commerce on the Internet such as video-on-demand and real-time video multicast. Traditional cryptographic algorithms/systems for data security are often not fast enough to process the vast amount of data generated by the multimedia applications to meet the real-time constraints. This paper presents a joint encryption and compression framework in which video data are scrambled efficiently in the frequency domain by employing selective bit scrambling, block shuffling and block rotation of the transform coefficients and motion vectors. The new approach is very simple to implement, yet provides considerable levels of security and different levels of transparency, and has very limited adverse impact on the compression efficiency and no adverse impact on error resiliency. Furthermore, it allows transcodability/scalability, and some other content processing functionalities without having to access the cryptographic key and to perform decryption and re-encryption.

关键词： contents access control joint encryption and compression multimedia encryption multimedia security selective encryption video scrambling

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Scheduling algorithms for packet-oriented MAC protocols in wireless multimedia systems

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WIRELESS PERSONAL COMMUNICATIONS 2003年第3期24卷 363-388页

作者： Fantacci, R Giambene, G Petiti, F Univ Florence Dipartimento Elettr & Telecommun I-50139 Florence Italy Univ Siena Dipartimento Ingn Informaz I-53100 Siena Italy Alcatel Italia Florence Italy

Future generation wireless multimedia communications will require efficient Medium access Control (MAC) protocols able to guarantee suitable Quality of Service (QoS) levels for different traffic classes while achieving a high utilization of radio resources. This paper proposes a new scheduling technique to be adopted at the MAC level in wireless access systems, named Dynamic Scheduling-Time Division Duplexing (DS-TDD), that efficiently manages video, voice, Web and background traffics. A theoretical approach is proposed in this paper to evaluate the DS-TDD performance with voice and Web traffics. Simulation results have permitted to highlight the following promising characteristics of the DS-TDD scheme: (i) a high capacity of real-time traffics is attained with a QoS insensitive to Web and background traffic loads;(ii) a high throughput can be guaranteed while preserving the QoS levels of the different traffic classes;(iii) heavier downlink traffic loads do not modify the QoS of uplink traffics. Finally, extensive comparisons with different scheduling schemes proposed in the literature have permitted to highlight the better performance of DS-TDD.

关键词： broadband wireless communications medium access control protocols scheduling techniques

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Media and metadata management for capture and access systems in electronic lecturing environments

Media and metadata management for capture and access systems...

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4th International Conference on multimedia and Expo (ICME 2003)

作者： Stewart, A Wolf, P Hemmje, M Fraunhofer IPSI Darmstadt Germany

ISBN: (纸本)0780379659

One of the main challenges facing web-based multimedia content creators today is the development of cost-effective digital media content for courseware that is reusable and interoperable. Given this, we propose the design and implementation of a model to manage the multimedia and meta-data within a system of related topics in a course that is delivered via electronic lectures. This model not only supports the re-purposing and interchange of a course's digital media content, but also preserves the semantic dependencies and associated media-mapping, of pre-requisite and co-requisite knowledge within a course. Coarse grain or topic-based segmentations of an electronic lecture are used as building blocks to automatically create new, media-rich, electronic lecture experiences of interest to a user and subject to the constraints imposed by the model.

关键词： Digital storage

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Strategies for video file replication based on multiple video popularity models

Strategies for video file replication based on multiple vide...

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Proceedings of the Seventh IASTED International Conference on Internet and multimedia systems and Applications

作者： Chan, Cheok-Kuan To, Tsun-Ping J. Li, Chi-Kwong Department of Electronic Engineering Hong Kong Polytechnic University Hung Hom SAR Hong Kong

ISBN: (纸本)0889863806

Fast Internet access technology (ADSL and VDSL) and the coming 3G mobile communication system of high data bandwidth capacity highly facilitate multimedia traffic demands by people. However, there are comparatively little technological advancements in the storage system, the essential part of VoD system. Disk array seems to be the most cost effective choice when I/O Bandwidths, disk space cost and scalability are all considered. The central question is how to offer more concurrent accesses to the videos(especially the popular ones) with the QoS requirements satisfied. In this paper, two replication algorithms are developed and evaluated. The system is modeled and evaluated by a SIMSCRIPT ii simulation program. The results illustrate that the two algorithms successfully manage disk resources to support more concurrent video stream.

关键词： multimedia systems

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Mobile Internet over IP data broadcast 10

Mobile Internet over IP data broadcast

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10th International Conference on Telecommunications (ICT 2003)

作者： Paila, T Nokia Electr Ltd Nokia Grp Helsinki Finland

ISBN: (纸本)0780376617

When speaking of wireless and mobile Internet, we often assume that a bi-directional access network must be within reach. Usually we see GPRS, UMTS and wireless LANs as carriers supporting the Internet access service. This service consequently provides a basis for browsing and retrieving a wealth of digital multimedia content upon user request. However, there are alternative means to deliver digital content to mobile users. Indeed, general content and content formats are independent from various communication methods. In this paper we focus on an alternative content delivery method - content push over terrestrial IP data broadcasting. To give a concrete context for discussion we assume DVB-T as transmission technology. The unidirectional, wide-band, shared channel suits especially well delivery service that targets multiple end users on the move. Applied to mobile communications, IP data broadcasting proves to complement the traditional mobile Internet access service provided over bi-directional access systems. From the viewpoint of international standards developing organizations, we tackle the issues needed to establish a globally inter-operable IP datacast baseline as a service platform.

关键词： 3G mobile communication Bidirectional control Broadcasting content based retrieval Ground penetrating radar IP networks Mobile communication multimedia communication Web and internet services Wireless LAN

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Toward flexible user interaction in content-based multimedia data retrieval

Toward flexible user interaction in content-based multimedia...

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作者： Nakazato, Munehiro University of Illinois at Urbana-Champaign

学位级别：Ph.D.

This thesis discusses various aspects of digital image retrieval and management. First, we discuss user interface and visualization for digital image management. Two innovative systems are proposed. 3D MARS is immersive 3D display for image visualization and search systems. The user browses and searches images in 3D virtual reality environment. ImageGrouper is another graphical user interface for digital image search and organization. New concept, Object-Oriented User Interaction is introduced. The system improves image retrieval and eases text annotation and organization of digital images. Unlike the traditional user interfaces for image retrieval, ImageGrouper allows the user to group query example images. To take advantage of this feature, a new algorithm for relevance feedback is proposed. Next, this thesis discusses data structures and algorithms for high-dimensional data access. This is an essential component of multimedia data retrieval. The results of preliminary experiments are presented.

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Layered semantic architecture of multimedia data

Layered semantic architecture of multimedia data

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Proceedings of the Seventh IASTED International Conference on Internet and multimedia systems and Applications

作者： Gong, Zhiguo Zhang, Jia Faculty of Science and Technology University of Macau P.O. Box 3001 Macao China infiNET Solutions 1425 E. Busch Parkway Buffalo Grove IL 60089 United States

ISBN: (纸本)0889863806

multimedia data, which are direct reflections of the real world, have unlimited semantic interpretations within different application domains. In order to reuse information resources, in this paper, we provide a layered architecture of multimedia schema - raw multimedia layer, domain knowledge layer, and user profile layer. Raw multimedia layer provides non-semantic management of data, including storage allocations, buffer algorithms and strategies, and multimedia preprocessing facilities. Domain knowledge layer provides semantic-oriented management and access of multimedia data. Different domains can utilize different knowledge bases to support semantic interpretations. We use Frame and Semantic Network as the representation models for domain knowledge. content-based retrievals can be performed on different levels of visual object constructions or concept abstractions. Furthermore, since different individual users may have different interpretations for fuzzy specifications in their queries, user profiles are created and used to support fuzzy retrievals of multimedia data.

关键词： multimedia systems

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HIT-DML: A novel Digital Music Library

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6th International Conference on Asian Digital Libraries

作者： Wang, CK Li, JZ Shi, SF Harbin Inst Technol Dept Comp Sci & Engn Harbin Heilongjiang Peoples R China

ISBN: (纸本)3540206086

The design and implementation of Harbin Institute of Technology-Digital Music Library (HIT-DML) is presented in this paper. HIT-DML adopts a novel framework which is inherently based on database systems. In this framework, musical data is structurally stored in the database, some algorithms of musical computation are implemented as algebraic mirco-operations in the database management system, and thus database technologies and multimedia technologies are combined seamlessly. A musical feature-matching algorithm and the appropriate dynamic index are also applied in HIT-DML. HIT-DML can retrieve musical information based on content, especially against different kinds of musical instruments.

关键词： Digital Music Library content-based music information retrieval

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Extending TINA with secure on-line accounting services

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Journal of Network and systems Management 2003年第4期11卷 379-397页

作者： Westphall, Carlos Becker Sekkaki, Abderrahim Alvarez, Luis Marco Cáceres Watanabe, Wagner Tatsuya P.-Grad. Prog. in Computer Science Technological Center Federal University of Santa Catarina Caixa Postal 476 88040-970 Florianopolis SC Brazil Department of Mathematics Faculty of Science - Ain Chock Hassan II University Casablanca Morocco

Concepts and principles of TINA (Telecommunications Information Networking Architecture) are introduced with the objective of correcting problems of the current centralized service control and service data model in an IN (Intelligent Network). It is becoming increasingly clear that the future sophisticated telecommunication services, e.g., multimedia, and multi-party conferencing, breaking away from the traditional telephony call model will need the solutions for rapid and efficient introduction, deployment, operations, and management. In this paper, we discuss accounting features and requirements, as well as security services in the TINA management context. We will introduce and present an implementation of a model for a security management, based on secure objects, cryptography and certificate distribution. In order to provide secure services, secure objects that have security functionality, such as authentication and access control, have been defined. Secure objects in our model are CORBA objects. The security domain is also called SBS (Security Base Server), provides security services and has an SMIB (Security Management Information Base) that contains security policies, cryptographic algorithms, and other relevant information. A prototype has been implemented and some experimental results are presented.

关键词： Online systems

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Supporting timeliness and accuracy in distributed real-time content-based video analysis

Supporting timeliness and accuracy in distributed real-time ...

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2003 multimedia Conference - Proceedings of the 11th ACM International Conference on multimedia, MM'03

作者： Eide, Viktor S. Wold Eliassen, Frank Granmo, Ole-Christoffer Lysne, Olav University of Oslo P.O. Box 1080 Blindern N-0314 Oslo Norway Simula Research Laboratory P.O. Box 134 N-1325 Lysaker Norway Agder University College Grooseveien 36 N-4876 Grimstad Norway

Real-time content-based access to live video data requires content analysis applications that are able to process the video data at least as fast as the video data is made available to the application and with an acceptable error rate. Statements as this express quality of service (QoS) requirements to the application. In order to provide some level of control of the QoS provided, the video content analysis application must be scalable and resource aware so that requirements of timeliness and accuracy can be met by allocating additional processing resources. In this paper we present a general architecture of video content analysis applications including a model for specifying requirements of timeliness and accuracy. The salient features of the architecture include its combination of probabilistic knowledge-based media content analysis with QoS and distributed resource management to handle QoS requirements, and its independent scalability at multiple logical levels of distribution. We also present experimental results with an algorithm for QoS-aware selection of configurations of feature extractor and classification algorithms that can be used to balance requirements of timeliness and accuracy against available processing resources. Experiments with an implementation of a real-time motion vector based object-tracking application, demonstrate the scalability of the architecture.

关键词： Real time systems

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