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A Rate Control Mechanism for Wireless Multimedia Sensor Networks
, M.Sc. Thesis Sharif University of Technology ; Khansari, Mohammad (Supervisor) ; Akbari, Behzad (Co-Advisor)
Abstract
To make Wireless Multimedia Sensor Networks (WMSNs) more practical, researchers have tried to meet its challenges in the last decade. Some factors of WMSNs, such as low bandwidth and channel errors, cause a decrease in the video quality that is declared as distortion. On the other hand, one important requirement in the context of multimedia streaming is its quality. In this thesis, we first introduce and use an adaptive cross-layer error control in the link layer, and then we implement a new cross-layer source rate control Mechanism for efficient and reliable real-time multimedia streaming in wireless sensor networks. Our main objective is to minimize distortion. Some of the used cross-layer...
Performance analysis of selected error control protocols in wireless multimedia sensor networks
, Article Proceedings - 18th Annual IEEE/ACM International Symposium on Modeling, Analysis and Simulation of Computer and Telecommunication Systems, MASCOTS 2010 ; 2010 , Pages 447-450 ; 9780769541976 (ISBN) ; Rabiee, H. R ; Khansari, M ; Sharif University of Technology
2010
Abstract
Error control is an important mechanism for providing robust multimedia communication in wireless sensor networks. Although there have been several research works in analysis of error control mechanisms in wireless multimedia networks and wireless sensor networks, but none of them are directly applicable to the wireless multimedia sensor networks (WMSNs) which has resource and performance constraints of WSNs as well as QoS requirements of multimedia communications. In this paper, we comprehensively evaluate the performance of several error control mechanisms in WMSNs. The results of our analysis provide an extensive comparison between automatic repeat request (ARQ), forward error correction...
Video-tampering detection and content reconstruction via self-embedding
, Article IEEE Transactions on Instrumentation and Measurement ; 2017 ; 00189456 (ISSN) ; Ghaemmaghami, S ; Sharif University of Technology
Abstract
Rapidly improving video-editing software tools and algorithms have made video content manipulation and modification feasible even by inexpert users. Detecting video tampering and recovering the original content of the tampered videos is, thus, a major need in many applications. Although detection and localization of the tampering in certain types of video editing have successfully been addressed in the literature, attempts for recovering the tampered videos are bound to methods using watermarks. In this paper, a scheme for the reconstruction of the tampered video through watermarking is proposed. The watermark payload, which consists of highly compressed versions of keyframes of the video...
A secure architecture for mobility management in heterogeneous networks in IMS
, Article 2009 1st International Conference on Networked Digital Technologies, NDT 2009, Ostrava, 28 July 2009 through 31 July 2009 ; 2009 , Pages 496-499 ; 9781424446155 (ISBN) ; Aghaie Khouzani, H ; Mozayani, N ; Sharif University of Technology
2009
Abstract
The IP Multimedia Subsystem is a basis for a significant new architecture which offers network operators the opportunity to expand their services, integrating voice and multimedia communications and delivering them into new environments with new purposes. The IMS is an overlay network on top of IP that uses SIP as the primary signaling mechanism. Using IMS bears several new security challenges. In this paper we provide an overview of IMS and its architecture. Then we represent a secure model to overcome some of IMS security challenges. ©2009 IEEE
Bandwidth-delay constrained least cost multicast routing for multimedia communication
, Article 13th International Computer Society of Iran Computer Conference on Advances in Computer Science and Engineering, CSICC 2008, Kish Island, 9 March 2008 through 11 March 2008 ; Volume 6 CCIS , 2008 , Pages 737-740 ; 18650929 (ISSN); 3540899847 (ISBN); 9783540899846 (ISBN) ; Forsati, R ; Movaghar, A ; Sharif University of Technology
2008
Abstract
A new meta-heuristic algorithm is proposed for constructing multicast trees in real-time multimedia applications such that satisfies two important Quality of Service (QoS) constraints. The QoS based multicast routing problem is a known NP-complete problem that depends on (1) bounded end-to-end delay and link bandwidth along the paths from the source to each destination, and (2) minimum cost of the multicast tree. We evaluate the performance and efficiency of the proposed method with a modified version of the BSMA algorithm which is the best known deterministic heuristic algorithm to delay-constrained multicast problem. Simulation results reveal that the proposed algorithm can achieve a...
Introducing a framework to create telephony speech databases from direct ones
, Article 14th International Conference on Systems Signals and Image Processing, IWSSIP 2007 and 6th EURASIP Conference Focused on Speech and Image Processing, Multimedia Communications and Services, EC-SIPMCS 2007, Maribor, 27 June 2007 through 30 June 2007 ; November , 2007 , Pages 327-330 ; 9789612480295 (ISBN) ; Sameti, H ; Vaisipour, S ; Tefagh, M ; Sharif University of Technology
2007
Abstract
A Comprehensive speech database is one of the important tools for developing speech recognition systems; these tools are necessary for telephony recognition, too. Although adequate databases for direct speech recognizers exist, there is not an appropriate database for telephony speech recognizers. Most methods suggested for solving this problem are based on building new databases which tends to consume much time and many resources; or they used a filter which simulates circuit switch behavior to transform direct databases to telephony ones, in this case resulted databases have many differences with real telephony databases. In this paper we introduce a framework for creating telephony speech...
Error control for multimedia communications in wireless sensor networks: A comparative performance analysis
, Article Ad Hoc Networks ; Volume 10, Issue 6 , 2012 , Pages 1028-1042 ; 15708705 (ISSN) ; Rabiee, H. R ; Khansari, M ; Salehi, M ; Sharif University of Technology
Abstract
The emerging multimedia applications of Wireless Sensor Network (WSNs) impose new challenges in design of algorithms and communication protocols for such networks. In the view of these challenges, error control is an important mechanism that enables us to provide robust multimedia communication and maintain Quality of Service (QoS). Despite the existence of some good research works on error control analysis in WSNs, none of them provides a thorough study of error control schemes for multimedia delivery. In this paper, a comprehensive performance evaluation of Automatic Repeat Request (ARQ), Forward Error Correction (FEC), Erasure Coding (EC), link-layer hybrid FEC/ARQ, and cross-layer hybrid...