For OFDM channels, we propose a content-aware subcarrier allocation scheme for multiuser video transmission that maximizes user perceived quality while minimizing power consumption. The scheme utilizes utility functio...
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ISBN:
(纸本)9781479912919
For OFDM channels, we propose a content-aware subcarrier allocation scheme for multiuser video transmission that maximizes user perceived quality while minimizing power consumption. The scheme utilizes utility function-based genetic algorithms to solve the multi-objective optimization problem. It significantly outperforms existing methods in terms of perceived quality and consumed power.
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 layer...
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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.
The multimedia data are more present in the actual informatics systems. Because of characteristics of multimedia data, their management and querying techniques are unlike than those of traditional data. We can increas...
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ISBN:
(纸本)9789537138158
The multimedia data are more present in the actual informatics systems. Because of characteristics of multimedia data, their management and querying techniques are unlike than those of traditional data. We can increase the potential use of multimedia data across various applications by assuring semantics-driven access to multimedia data. In this paper we propose a solution, based on MPEG-21 standard, to describe the multimediacontent and to integrate it with the semantic web.
The paper describes a system to manage the distribution of multimediacontent over IP with the support of QoS and fine grained access control. It relies on visual languages to simplify the specification of complex acc...
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Users desire to use multimedia applications such as browsing WWW and VoD in not only desktop computing environment but also wireless or mobile computing environment. A wireless link, however, is generally poor in qual...
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ISBN:
(纸本)0780339061
Users desire to use multimedia applications such as browsing WWW and VoD in not only desktop computing environment but also wireless or mobile computing environment. A wireless link, however, is generally poor in quality to accommodate multimedia communication. We propose a content-based multimedia communication protocol for wireless environment. It adopts the selective transport service according to content-based priority, assigned to each scene of multimedia data, so that a user can get important information even if available bandwidth is insufficient for the multimedia data.
The paper presents an MPEG-7 multimedia Description Schemes (MDS)-based metadata and user profile model used within,in enhanced DTV environment for semantic annotation and personalized access to multiple sports DTV se...
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ISBN:
(纸本)0780393317
The paper presents an MPEG-7 multimedia Description Schemes (MDS)-based metadata and user profile model used within,in enhanced DTV environment for semantic annotation and personalized access to multiple sports DTV services. It is shown that in order to enable intelligent and personalized processing, management and use of multimediacontent and services, the use of application specific metadata descriptions and adequately formulated user profiles is most important. Thus, application specific semantic metadata and user profile definitions are presented in this paper. Metadata and user profile instances are generated by Authoring/Annotation tools or User Profile Registration client applications respectively. Personalized access to sports DTV services is achieved by metadata and user profile instance description matching and content filtering at either the server or the client side. At the same time, dynamic client configuration, transparent to the end-User, is accomplished by automatically processing configuration specific metadata descriptions using specially designed application modules at the client side. The main purpose is to enable personalized integrated multimedia services access in the sports domain over DTV infrastructures.
This article describes primarily the development and empiric validation of a design for security warning messages on smartphones for primary school children (7-10 years old). Our design approach for security warnings ...
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ISBN:
(纸本)9780819489517
This article describes primarily the development and empiric validation of a design for security warning messages on smartphones for primary school children (7-10 years old). Our design approach for security warnings for children uses a specific character and is based on recommendations of a paediatrician expert. The design criteria are adapted to children's skills, e. g. their visual, acoustic, and haptic perception and their literacy. The developed security warnings are prototypically implemented in an iOS application (on the iPhone 3G/4G) where children are warned by a simulated anti-malware background service, while they are busy with another task. For the evaluation we select methods for empiric validation of the design approach from the field of usability testing ("think aloud" test, questionnaires, log-files, etc.). Our security warnings prototype is evaluated in an empiric user study with 13 primary school children, aged between 8 and 9 years and of different gender (5 girls, 8 boys). The evaluation analysis shows, that nearly all children liked the design of our security warnings. Surprisingly, on several security warning messages most of the children react in the right way after reading the warning, although the meaning couldn't be interpreted in the right way. Another interesting result is, that several children relate specific information, e. g. update, to a specific character. Furthermore, it could be seen that most of the primary school test candidates have little awareness of security threats on smartphones. It is a very strong argument to develop e. g. tutorials or websites in order to raise awareness and teach children how to recognize security threats and how to react to them. Our design approach of security warnings for children's smartphones can be a basis for warning on other systems or applications like tutorials, which are used by children. In a second investigation, we focus on webpages, designed for children since smartphones and webpages (t
The sharing, distribution and transmission of proliferated digital multimediacontents over the insecure worldwide available Internet and wired/wireless networks has encouraged the copyright fraud, unauthorized access...
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ISBN:
(纸本)9783642292156
The sharing, distribution and transmission of proliferated digital multimediacontents over the insecure worldwide available Internet and wired/wireless networks has encouraged the copyright fraud, unauthorized access and illegal usage. This brings new technical challenges to provide the end-to-end security to multimediacontents for establishing ownership rights, ensuring authorized access, preventing illegal replication etc. To address the above mentioned requirements, a visual multimediacontent protection technique is proposed. The technique is based on the high dynamic responses of multiple high-dimensional chaotic systems. The multimedia encryption is achieved by randomly picking the actual encryption keys out of numbers of hybridized keys that are extracted from complex sequences of three high dimensional chaotic systems. Accordingly, a high encryption effect is turned up in the encrypted content. The proposed technique is experimented on the multimedia color imagery. The decomposed R, G, B components of color plain-image are initially diffused with their self, before diffusing with encryption keys. It is experimentally verified that the proposed technique has great encryption performance and achieves high confidential security. Eventually, the statistical results confirm the practicability and suitability of the approach for visual multimediacontent protection.
Traditional cryptography systems treat every portion of a message (a video, an image, or an audio) equally and encrypt the entire message as a whole. As a result, those security systems often have only two states: acc...
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In the current multimedia networked infrastructure, privacy breaches due to cyber-attacks result in huge economic losses. Despite these threats there is ever increasing demand to share data over various insecure netwo...
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In the current multimedia networked infrastructure, privacy breaches due to cyber-attacks result in huge economic losses. Despite these threats there is ever increasing demand to share data over various insecure networks for accomplishment of numerous tasks. In such a scenario there is a greater need to develop new algorithms for strengthening the existing cybersecurity frameworks, ensure security, privacy, copyright protection and authentication of data. In this paper a new technique for copyright protection, data security and content authentication of multimedia images is presented. The copyright protection of the media is taken care of by embedding a robust watermark using an efficient inter-block coefficient differencing algorithm and is proposed as Scheme I. Scheme II has been utilized to ensure both copyright protection, and content authentication. The authentication of the content has been ensured by embedding a fragile watermark in spatial domain while as copyright protection has been taken care of utilizing a robust watermark. In order to thwart an adversary and ensure that it has no access to actual embedded data, we make use of a novel encryption algorithm in conjunction with Arnold transform to encrypt data prior to its embedding. The experimental results reveal that the proposed framework offers high degree of robustness against single/dual/triple attacks;with Normalized Correlation (NCC), more than or equal to 0.95. Besides, the fragile watermark embedding makes the system capable of tamper detection and localization with average BER more than 45% for all signal processing/geometric attacks. The average PSNR achieved for both schemes is greater than 41 dB. A comparison of the proposed framework with various state-of-the-art techniques demonstrate its effectiveness and superiority. (C) 2018 Elsevier B.V. All rights reserved.
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