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IEEE Pacific Rim conference on Communications, Computers and Signal Processing

作者： Y.S. Abdel-Hamid T.A. Gulliver Department of Electrical and Computer Engineering University of Victoria Victoria BC Canada

Downloading a large file through a heavily congested link can be difficult and frustrating, especially with frequent software updates and multimedia content. A common approach employed on the Internet is to utilize mirror sites. Luby et al proposed a new class of erasure codes for mirror site systems called Tornado codes. Tornado codes typically have much faster decoding times than Reed-Solomon (RS) codes. In this paper, we present an extensive study of the behavior of multiple mirror site systems. OPNET is employed to do a comparison study of system performance using RS and Tornado codes.

关键词： Internet Mirrors Tornadoes Decoding Feedback Reed-Solomon codes Network servers Forward error correction System performance Unicast

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Virtual face image generation for illumination and pose insensitive face recognition

Virtual face image generation for illumination and pose inse...

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IEEE International conference on multimedia and Expo (ICME)

作者： Wen Gao Shiguang Shan Xiujuan Chai Xiaowei Fu Department of Computer Science Harbin Institute of Technology Harbin China Institute of Computing Technology CAS Beijing China

ISBN: (纸本)0780376633

Face recognition has attracted much attention in the past decades for its wide potential applications. Much progress has been made in the past few years. However, specialized evaluation of the state-of-the-art in both academic algorithms and commercial systems illustrates that the performance of most current recognition technologies degrades significantly due to the variations of illumination and/or pose. To solve these problems, providing multiple training samples to the recognition system is a rational choice. However, enough samples are not always available for many practical applications. It is an alternative to augment the training set by generating virtual views from one single face image, that is relighting the given face images of synthesize novel views of the given face. Based on this strategy, this paper presents some attempts by presenting a ratio-image based face relighting method and a face re-rotating approach based on linear shape prediction and image warp. To evaluate the effect of the additional virtual face images, primary experiments are conducted using our specific substance method as face recognition approach, which shows impressive improvement compared with standard benchmark face recognition methods.

关键词： Image generation Lighting Face recognition Image recognition content addressable storage Computer science Application software Degradation Shape Business

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Indexing high-dimensional data for content-based retrieval in large databases

Indexing high-dimensional data for content-based retrieval i...

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International conference on Database systems for Advanced Applications

作者： M.J. Fonseca J.A. Jorge Department of Information Systems and Computer Sciences Technical University of Lisbon INESC-ID/IST Lisboa Portugal

Many indexing approaches for high-dimensional data points have evolved into very complex and hard to code algorithms. Sometimes this complexity is not matched by increase in performance. Motivated by these ideas, we take a step back and look at simpler approaches to indexing multimedia data. In this paper we propose a simple, (not simplistic) yet efficient indexing structure for high-dimensional data Points of variable dimension, using dimension reduction. Our approach maps multidimensional points to a 1D line by computing their Euclidean Norm and use a B/sup +/-Tree to store data points. We exploit B/sup +/-Tree efficient sequential search to develop simple, yet performant methods to implement point, range and nearest-neighbor queries. To evaluate our technique we conducted a set of experiments, using both synthetic and real data. We analyze creation, insertion and query times as a function of data set size and dimension. Results so far show that our simple scheme outperforms current approaches, such as the Pyramid Technique, the A-Tree and the SR-Tree, for many data distributions. Moreover, our approach seems to scale better both with growing dimensionality and data set size, while exhibiting low insertion and search times.

关键词： Indexing Information retrieval content based retrieval Spatial databases Technical drawing Nearest neighbor searches Image databases Data structures Information systems Computer science

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Caching policy assisted multicast patching for video streaming on-demand server

Caching policy assisted multicast patching for video streami...

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Asia-Pacific conference on Communications

作者： Jian-zheng Zhou Jian-guo Jiang Mei-bin Qi School of Computer & Information Hefei University of Technology Hefei China

ISBN: (纸本)0780381149

Video streaming on-demand servers are characterized by stringent real-time constraints, as each video stream requires isochronous data playout. With heavily skewed access patterns to the stored video content, the VOD system is often disk arm-bound. In such cases, serving video streams from a memory cache can result in a substantial reduction in server cost. With the falling prices of the memory, buffering and caching becomes an efficient method to reduce the required disk bandwidth. Most of the existing caching policies for video streaming on-demand server are designed in the context of unicast; however, using unicast will overload both network and server. Caching policies assisted with multicast will be more efficient and more scalable. Thus almost all extant caching algorithms are not suitable to be applied in actual multicast systems. In this paper we advance a new caching policy, which has fully combined the characteristics of an efficient multicast algorithm, for VOD server. This caching policy is very efficient, owing to a novel concept of entity and a unique caching gain function.

关键词： Streaming media Multicast algorithms Network servers Unicast Video on demand Bandwidth Costs content based retrieval Resource management Asset management

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Distributed content-aware Request Distribution in Cluster-based Web Servers

Distributed Content-aware Request Distribution in Cluster-ba...

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The Fourth International conference on Parallel and Distributed Computing, Applications and Technologies

作者： DU Zeng-Kai JU Jiu-Bin Department of Computer Science Jilin University

While content-aware distribution policies getting more popular in cluster-based web systems,they make the dispatching node a *** achieve scalable server performance,we present a completely distributed architecture in which all hosts participate in request *** cope with the architecture,we propose a distributed dispatching policy named *** DWARD,all the server nodes may participate in request dispatching on the basis of local access *** addition, the DWARD policy inherits several desirable features of the centralized algorithms,including load balance,high locality and less forwarding ***,a testbed is implemented on the basis of Linux kernel to benchmark various dispatching *** performance results show that DWARD can achieve favorable throughput compared with state-of-the-art dispatching policies.

关键词： Distributed web server content-based fault tolerance scalability

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A format-compliant configurable encryption framework for access control of video

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IEEE TRANSACTIONS ON CIRCUITS AND systems FOR VIDEO TECHNOLOGY 2002年第6期12卷 545-557页

作者： Wen, JT Severa, M Zeng, WJ Luttrell, MH Jin, WY PacketVideo Corp San Diego CA 92121 USA PhatNoise Inc Los Angeles CA 90064 USA Univ So Calif Dept Elect Engn Los Angeles CA 90007 USA

In this paper, we introduce new methods of performing selective encryption and spatial/frequency shuffling of compressed digital content that maintain syntax compliance after content has been secured. The tools described in this paper have been proposed to the MPEG-4 Intellectual Property Management and Protection (IPMP) standardization group and have been adopted into the MPEG-4 IPMP Final Proposed Draft Amendment (FPDAM) [9]. We will describe the application of the new methods to the protection of MPEG-4 video content in the wireless environment, and illustrate how they are used to leverage established encryption algorithms for the protection of only the information fields in the bitstream that are critical to the reconstructed video quality, while maintaining compliance to the syntax of MPEG-4 video, and thereby reduces the amount of data to be encrypted and guarantees the inheritance of many of the nice properties of the unprotected bitstreams that have been carefully studied and built, such as error resiliency and network friendliness. The encrypted content bitstream works with many existing random access, network bandwidth adaptation, and error control techniques that have been developed for standard-compliant compressed video, thus making it especially suitable for wireless multimedia applications. Standard compliance also allows subsequent signal processing techniques to be applied to the encrypted bitstream.

关键词： digital rights management encryption wireless multimedia distribution

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Personalized multimedia information spaces

Personalized multimedia information spaces

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2nd International conference on Image and Graphics

作者： Correia, N Univ Nova Lisboa FCT Dept Comp Sci Lisbon Portugal

ISBN: (纸本)0819446564

This paper presents and-integrated view of personalized information spaces. The topics that are described cover different dimensions of describing, customizing, reusing and presenting multimedia content. In order to have personalized multimedia content the systems should provide the ability to access it when and where it is necessary, in a way that is appropriate for each specific user. The paper describes several multimedia information processing and visualization systems that explore these concepts. More specifically, the applications and systems include annotation tools for describing and enhancing multimedia content, personalization and customization techniques, and tools for anytime, anywhere access to multimedia information. The examples of information access are an augmented reality system and applications for mobile devices, representing two of the dominant and convergent trends in ubiquitous computing.

关键词： Video multimedia Video processing Visualization Mobile devices 3D modeling Augmented reality 3D image processing Image processing Cell phones

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A key transport protocol based on secret sharing applications to information security

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IEEE TRANSACTIONS ON CONSUMER ELECTRONICS 2002年第4期48卷 816-824页

作者： Eskicioglu, AM Delp, EJ Purdue Univ Sch Elect & Comp Engn VIdeo & Image Proc Lab W Lafayette IN 47907 USA

Digital multimedia content is delivered to homes via the Internet, satellite, terrestrial and cable networks. Scrambling is a common approach used by conditional access systems to prevent unauthorized access to audiovisual data. The descrambling keys are securely distributed to the receivers in the same transmission channel. Their protection is an important part of the key management problem. Although public-key cryptography provides a viable solution, alternative methods are sought for economy and efficiency. Message authentication is an important objective of information security in modern electronic distribution networks. This objective is met by providing the receiver of a message an assurance of the sender's identity. As physical protection such as sealed envelopes is not possible for messages expressed as binary sequences, digital tools have been developed using cryptography. A major limitation of all cryptographic methods for message authentication lies in their use of algorithms with fixed symmetric or public keys. This paper presents a key transport protocol based on secret sharing. Conditional access and message authentication are two important application areas for which the advantages of the proposed protocol are discussed. The protocol eliminates the need for a cipher, yet effectively combines the advantages of symmetric and public-key ciphers. It can be used to build a new key management scheme that allows the service providers to generate different keys for different sets of receivers, and to renew these keys in a convenient way.

关键词： cipher conditional access content protection data integrity digital signature encryption hashing key transport message authentication multimedia public-key cryptography prepositioned secret sharing

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multimedia content management in MPEG-21 framework

Multimedia content management in MPEG-21 framework

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Internet multimedia Management systems III conference

作者： Smith, JR IBM Corp TJ Watson Res Ctr Hawthorne NY 10532 USA

ISBN: (纸本)0819446416

MPEG-21 is an emerging standard from MPEG(1) that specifies a framework for transactions of multimedia content. MPEG-21 defines the fundamental concept known as a digital item, which is the unit of transaction in the multimedia framework. A digital item can be used to package content for such as a digital photograph, a video clip or movie, a musical recording with graphics and liner notes, a photo album, and so on. The packaging of the media resources, corresponding identifiers, and associated metadata is provided in the declaration of the digital item. The digital item declaration allows for more effective transaction, distribution, and management of multimedia content and corresponding metadata, rights expressions, variations of media resources. In this paper, we describe various challenges for multimedia content management in the MPEG-21 framework.

关键词： multimedia content management multimedia system support and delivery multimedia processing and coding universal multimedia access content adaptation pervasive computing rights management MPEG-7 MPEG-21

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Metadata-based access to multimedia architectural and historical archive collections

Metadata-based access to multimedia architectural and histor...

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Internet multimedia Management systems III conference

作者： Bekaert, J Van De Ville, D Rogge, B Lerouge, S De Sutter, R De Kooning, E Van de Walle, R State Univ Ghent Dept Elect & Informat Syst ELIS Multimedia Lab B-9000 Ghent Belgium

ISBN: (纸本)0819446416

A comprehensive approach to the access of archival collections necessitates the interplay of various types of metadata standards. Each of these standards fulfills its own part within the context of a 'metadata infrastructure'. Besides this, it should be noted that present-day digital libraries are often limited to the management of mainly textual and image-based material. Archival Information systems dealing with various media types are still very rare. There is a need for a methodology to deal with time-dependant media within an archival context. The aim of our research is to investigate and implement a number of tools supporting the content management multimedia data within digital collections. A flexible and extendible framework is proposed, based on the emerging Metadata Encoding and Transmission Standard (METS). Firstly, we will focus on the description of archival collections according to the archival mandates of provenance for the benefit of an art-historical research in an archive-theoretic ally correct manner. Secondly, we will examine the description tools that represent the semantics and structure of multimedia data. In this respect, an extension of the present archival metadata framework has been proposed to time-based media content delivered via standards such as the MPEG-7 multimedia content description standard.

关键词： multimedia archival collections metadata METS MPEG-7

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