Digital rights management systems enable the distribution and use of multimediacontent in a controlled way through the complete digital value chain. The terms and conditions of use, delivery and access to multimedia ...
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Digital rights management systems enable the distribution and use of multimediacontent in a controlled way through the complete digital value chain. The terms and conditions of use, delivery and access to multimediacontent are specified using a Rights Expression Language. A REL is a formal language designed to define the permissions and constraints of use of multimediacontent. Creative Commons has defined different types of licenses to govern digital works when publishing them. Nevertheless, these licenses do not use a specific REL. A key issue is to express CC licenses using a REL. Then, DRM systems can control the use of the governed digital works. This paper presents two approaches to express CC licenses using the MPEG-21 REL
Scheduling algorithms play a key role in overall system performance of broadband wireless systems (BWS) such as WLAN/WMAN. Maximal SNR (MaxSNR) and Round Robin (RR) are two conventional scheduling strategies which emp...
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Scheduling algorithms play a key role in overall system performance of broadband wireless systems (BWS) such as WLAN/WMAN. Maximal SNR (MaxSNR) and Round Robin (RR) are two conventional scheduling strategies which emphasize efficiency and fairness respectively. Proportional Fair (PF) algorithm provides tradeoff between efficiency and fairness and it has been well studied in TDMA and CDMA systems. In this paper, we apply the PF scheduling algorithm to IEEE 802.16a OFDM based BWS and call it OPF. In addition, we propose three algorithms for multimedia services: (1) Adaptive OPF (AOPF), (2) multimedia AOPF (MAOPF) and (3) Normalized MAOPF (NMAOPF). Adaptive modulation and coding schemes are applied to combat the time varying nature of the wireless channels. System performances of all six algorithms are compared in terms of efficiency and fairness.. Joint PHY and MAC layer simulation results show that the proposed schemes provide better tradeoff between efficiency and fairness than conventional algorithms.
The paper proposes an effective adaptive p-persistent-based (APP) medium access control (MAC) scheme for WLAN-based dedicated short-range communications (DSRC) networks supporting multimedia services. The APP MAC sche...
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The paper proposes an effective adaptive p-persistent-based (APP) medium access control (MAC) scheme for WLAN-based dedicated short-range communications (DSRC) networks supporting multimedia services. The APP MAC scheme adaptively gives differentiated permission probabilities to on board units (OBUs) which are in different access category and with various waiting delay. Simulation results show that the APP MAC scheme can improve the performance of multimedia WLAN-based DSRC networks, such as small real-time packet dropping probability, low delay variation, and high system throughput, compared to conventional MAC algorithms
Pictures and video sequences showing human faces are of high importance in content-based retrieval systems. During flourishing Internet time, more and more human face image databases are stored on the Internet. They p...
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ISBN:
(纸本)8955191294
Pictures and video sequences showing human faces are of high importance in content-based retrieval systems. During flourishing Internet time, more and more human face image databases are stored on the Internet. They provide a great number of human face images to access. Therefore, considering the storage space and the network bandwidth, how to access human face image more efficiently has become an important topic. The primary goal of our method is to minimize the number of bits required to preserve the crucial facial features without any loss of information. In this paper, we propose a new technique based on JPEG2000 for the storage and retrieval of the human face images. We combine lossy and lossless image compression of JPEG2000 to reach our goal. Aiming at the feature of human face image data, we will extract the facial features in the image as the most important information. The lossless image compression is used to retain the facial features of human face image. The background and the rest of the image are processed by lossy compression to further save the required storage space. The preliminary result has shown that our method can have higher compression ratio without loss of the crucial facial feature for low bandwidth communication applications, such as videophone and teleconferencing.
In a digital TV system, the Conditional access (CA) system is essential to protect programs from unauthorized access. However, the encryption technique alone is not sufficient to protect or control the use of contents...
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In a digital TV system, the Conditional access (CA) system is essential to protect programs from unauthorized access. However, the encryption technique alone is not sufficient to protect or control the use of contents after decryption. To provide flexible and complete Digital Rights Management (DRM) protection on the Digital Video Broadcasting (DVB) programs, we propose a method that adapts the MPEG- 21 REL technology and integrates it into a DVB-T system. By extending the Service Information (SI) section of a DVB stream to include an REL license, the transmitted content can be conveniently consumed and legally protected. Our design is verified by an experimental hardware system. The results show that the proposed method can provide both the conditional access functionality and the usage control of broadcasted contents.
Media consumers who are overwhelmed by multitudinous news content demand a system that would sift through tens or hundreds of broadcast TV channels on a daily basis to capture the most important clips that match users...
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Media consumers who are overwhelmed by multitudinous news content demand a system that would sift through tens or hundreds of broadcast TV channels on a daily basis to capture the most important clips that match users' interests and deliver these personalized clips for easy viewing on a typical TV or home PC. In this paper, we present a personal media alert system that extracts video segments for the interested users. In addition, alerts with pointers to content stored on the home server can be sent to mobile users who are authorized to access the content at home. To make content sharing feasible and scalable, we also propose a P2P payment scheme that would allow a consumer to have access to media clips aggregated on other consumers' personal media systems
The following topics are dealt with: image processing; content understanding; encoding; H.264; VLSI system-on-chip integrated multimediasystems; media signal processing; forensic analysis; P2P multimedia streaming; m...
The following topics are dealt with: image processing; content understanding; encoding; H.264; VLSI system-on-chip integrated multimediasystems; media signal processing; forensic analysis; P2P multimedia streaming; mobile networks; digital watermarking, data hiding and steganography; multi-user collaboration and cross layer optimization in wireless; audio and speech processing; QoS; face detection; query processing and retrieval; protocols; encryption and access control
This paper provides a brief overview of recent progress of peer-to-peer (P2P) technologies for multimedia applications. We provide an overview of the technical challenges, creative solutions and results related to P2P...
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This paper provides a brief overview of recent progress of peer-to-peer (P2P) technologies for multimedia applications. We provide an overview of the technical challenges, creative solutions and results related to P2P file sharing and content search, and P2P media streaming
multimediacontent repurposing is a new challenge in distributing multimediasystems due to the heterogeneity of client devices and their network connections. This paper addresses the problem of heterogeneity and prop...
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multimediacontent repurposing is a new challenge in distributing multimediasystems due to the heterogeneity of client devices and their network connections. This paper addresses the problem of heterogeneity and proposes a solution that uses a series of repurposing proxies in a chain fashion. In order to find the best scalable repurposing service among those proxies, two modified versions of the shortest path selection algorithms have been implemented. The scalability of the services has been measured in terms of user satisfaction. An implemented Java-based prototype as well as computer simulation results shows the viability of our approach
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