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Fast application-level video quality evaluation for extensive error-prone channel simulations

Fast application-level video quality evaluation for extensiv...

2010 15th IEEE International Workshop on Computer Aided modeling, Analysis and Design of Communication Links and Networks, CAMAD 2010

作者： Skupin, Robert Hellge, Cornelius Schierl, Thomas Wiegand, Thomas Fraunhofer HHI Image Processing Department Germany Technische Universität Berlin Image Communication Group Germany

ISBN: (纸本)9781424476350

Video transmission over error prone channels, such as typical for Mobile TV or IPTV systems, is constantly subject to research. simulation is an important instrument to evaluate performance of the overall system, but the multitude of parameters often requires large and time-consuming simulation sets. In this paper, we present a mechanism for fast evaluation of error-prone H.264/AVC and SVC video transmission with application-level metrics. Our approach significantly reduces overall simulation time by eliminating redundancy in the evaluation phase and utilizing the prediction structure of H.264/AVC and SVC. The benefit of the presented approach is evaluated with an exemplary simulation setup of a Mobile TV scenario via DVB-H. © 2010 IEEE.

关键词： Quality control

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3D stochastic cloud generation for performance evaluation of space-based optical system

3D stochastic cloud generation for performance evaluation of...

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2010 3rd International Congress on image and signal processing, CISP 2010

作者： Cao, Yiming Zhang, Wei Zhang, Yin Cong, Mingyu Nie, Hongbin Bao, Wenzhuo Research Center for Space Optical Engineering Harbin Institute of Technology Harbin China

ISBN: (纸本)9781424465149

A three-dimensional (3D) stochastic cloud generation architecture is developed to simulate radiative scenes for performance evaluation of space-based optical system. The rescale-and-add fractal algorithm is employed to generate internal and external structure data of clouds. The Spherical Harmonic Discrete Ordinate (SHDOM) code is selected to solve the 3D radiative transfer equation numerically. The flowchart of the simulation system is shown. The methods for generating 3D grid data of cloud spatial structure and liquid water content (LWC), as well as the radiative quantities, are presented. Two types of clouds are generated as illustrations. Radiative cloud scenes under different imaging conditions could be conveniently available using this framework. The simulation results demonstrate the effectiveness of the proposed methods and architecture. ©2010 IEEE.

关键词： Stochastic systems

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evaluation of space-time block codes under controlled fading conditions using hardware simulation

Evaluation of space-time block codes under controlled fading...

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作者： Colavito, Leonard R Temple University

学位级别：Ph.D.

Space time block codes (STBC) are a type of multiple input multiple output (MIMO) communications system that encode blocks of information into symbol sequences sent simultaneously from multiple antennas. MIMO communications systems have shown channel capacity improvement in multipath digital communications environments. The STBC class of MIMO communications systems can be easily decoded using linear combination and is resilient in the face of multipath channel effects.@pqdt@break@MIMO systems have traditionally been studied using theoretical analyses, simulations and real signal based experiments. Probabilistic models simulate channel effects as random variables, but are only estimates of actual conditions. Real signal experiments evaluate system performance under real-world conditions, but are not readily repeatable. Both modeling methods evaluate system performance in terms of the aggregate results.@pqdt@break@This dissertation research presents an approach that introduces controlled attenuation and delay to probabilistic channel models. This method allows the evaluation of MIMO system performance under specific channel conditions. The approach is demonstrated with a hardware accelerated STBC system model that is used to evaluate the performance of a MIMO system under controlled path conditions.@pqdt@break@The STBC system model utilizes a XilinixRTM programmable gate array (PGA) device as a hardware accelerator. The model exploits the parallel processing capability of the PGA to simulate a nine path channel model and a three antenna rate ½ STBC. Novel implementations are developed for the additive white Gaussian noise (AWGN) sources and the linear MIMO decoding in PGA hardware. The model allows specification of overall noise and multipath fading effects for the channel as well as attenuation and phase delay for each channel path. performance of the communications system is evaluated in terms of bit error rate (BER) versus signal-to-noise ratio (SNR).@pqdt@b

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evaluation of space-time block codes under controlled fading conditions using hardware simulation.

Evaluation of space-time block codes under controlled fading...

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作者： Colavito, Leonard R., Ph.D. Temple University

学位级别：Doctor

Space time block codes (STBC) are a type of multiple input multiple output (MIMO) communications system that encode blocks of information into symbol sequences sent simultaneously from multiple antennas. MIMO communications systems have shown channel capacity improvement in multipath digital communications environments. The STBC class of MIMO communications systems can be easily decoded using linear combination and is resilient in the face of multipath channel effects. MIMO systems have traditionally been studied using theoretical analyses, simulations and real signal based experiments. Probabilistic models simulate channel effects as random variables, but are only estimates of actual conditions. Real signal experiments evaluate system performance under real-world conditions, but are not readily repeatable. Both modeling methods evaluate system performance in terms of the aggregate results. This dissertation research presents an approach that introduces controlled attenuation and delay to probabilistic channel models. This method allows the evaluation of MIMO system performance under specific channel conditions. The approach is demonstrated with a hardware accelerated STBC system model that is used to evaluate the performance of a MIMO system under controlled path conditions. The STBC system model utilizes a Xilinix® programmable gate array (PGA) device as a hardware accelerator. The model exploits the parallel processing capability of the PGA to simulate a nine path channel model and a three antenna rate 1⁄2 STBC. Novel implementations are developed for the additive white Gaussian noise (AWGN) sources and the linear MIMO decoding in PGA hardware. The model allows specification of overall noise and multipath fading effects for the channel as well as attenuation and phase delay for each channel path. performance of the communications system is evaluated in terms of bit error rate (BER) versus signal-to-noise ratio (SNR). Hardware acceleration greatly redu

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SU-E-T-263: Development of a Video Guided Real-Time Patient Motion Monitoring System

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Medical Physics 2011年第6PART14期38卷 3547-3547页

作者： C Hong S Ju J Kim J Shin E Shin Y Han Y Ahn H Park D Choi W Huh Samsung Medical Center Sungkyunkwan University School of Medicine Seoul KR Myongji University Yongin Gyeonggido KR

Purpose: Using conventional CCD camera systems, we developed a video image guided real-time patientˈs motion monitoring (VGRPM) system; a motion phantom was used for evaluation of its performance for clinical use. Methods: The VGRPM system consists of three parts: an image acquisition device, a main control computer, and in-house developed patient motion analysis software. For development of an intelligent patient motion monitoring system that works only during treatment time and for system automation, the system was designed for synchronization with a beam on/off trigger signal. Patient movement during radiation is detected by real-time frame difference based in-house developed analysis software. When the error range exceeds the set criteria, (Cmove), a warning message is generated in the form of light and sound. The described procedure repeats automatically for each patient. A motion phantom, which operates by moving a distance of 0.5, 1, and 2 cm for 1 and 2 sec, respectively, was used for evaluation of system performance. We measured optimal Cmove for clinical use, minimum distance, which can be detected in this system, and response time of the whole system. The stability of the system in a linear accelerator unit was evaluated for a period of 6 months. Results: : As a result of the moving phantom test, the Cmove for detection of all simulated phantom motion was determined to be 0.5%. The system can detect phantom motion as small as 0.5 cm. The measured response time from detection of phantom movement to warning signal through video analysis was 0.1 sec. During this testing period, no significant functional disorder was observed. Conclusions: The VGRPM system can contribute to reduction of treatment error by patientˈs motion and increase the accuracy of treatment dose delivery.

关键词： Computer software Charge coupled devices systems analysis image analysis Computer systems Computer simulation Digital image processing Cameras Medical imaging image motion analysis

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Medium access control scheme for supporting user mobility in digital video broadcasting-return channel via satellite/satellite second generation - general architecture and functionalities

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IET COMMUNICATIONS 2010年第13期4卷 1532-1543页

作者： Celandroni, N. Davoli, F. Ferro, E. Gotta, A. CNR ISTI Inst CNR Res Area I-56124 Pisa Italy Univ Genoa DIST I-16145 Genoa Italy Univ Genoa CNIT Res Unit I-16145 Genoa Italy

This study aims at summarising the work done in the SatNEx project for the development and the performance evaluation of a new access scheme for multimedia data transmissions in digital video broadcasting-return channel via satellite (DVB-RCS)/satellite second generation (S2), applied to a mobile environment. The work has been stimulating because, as far as the authors know, this research topic has not yet been fully addressed in the literature. The authors started thinking about a realistic scenario of mobility, where novel services could be offered;having defined the scenario, the authors developed a satellite access scheme suitable for transmission control protocol (TCP) sessions and video streams in mobility. In this study, the authors present the reference architecture, the access scheme, the choice of the most suitable transmission parameters and the simulation results that are obtained when transmitting the two different types of data.

关键词： digital video broadcasting transmission control protocol Satellite communication systems Protocols transmission parameters mobile satellite communication satellite access scheme multimedia data transmissions video streaming Mobile radio systems broadcast channels Optical, image and video signal processing mobile environment digital video broadcasting return channel satellite second generation Radio and television broadcasting transport protocols medium access control scheme multimedia communication SatNEx project video stream Multimedia communications user mobility

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An evaluation Study of Mobility Support in ZigBee Networks

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JOURNAL OF signal processing systems FOR signal image AND VIDEO TECHNOLOGY 2010年第1期59卷 111-122页

作者： Chen, Ling-Jyh Sun, Tony Liang, Nia-Chiang Acad Sinica Inst Informat Sci Taipei Taiwan PacketMotion Inc San Jose CA USA Google Inc Mountain View CA USA

Based on the IEEE 802.15.4 LR-WPAN specification, the ZigBee standard has been proposed to interconnect simple, low rate, and battery powered wireless devices. The deployment of ZigBee networks is expected to facilitate numerous applications, such as home healthcare, medical monitoring, consumer electronics, and environmental sensors. For many of the envisioned applications, device mobility is unavoidable and must be accommodated. Thus, providing ubiquitous connections to/from a mobile device is crucial for various future ZigBee applications. Knowledge of how nodal mobility affects the ZigBee routing protocol is important, but the lack of ZigBee simulator support has limited the amount of research, evaluation, and development in this area. Thus far, researchers have been unable to analyze and evaluate the impact of mobile applications via extensive simulations. In this paper, our contribution is threefold. First, we present an initial implementation of the ZigBee network layer in NS-2, which will allow further research and development to be conducted in this area. Second, we analyze the adequacy of current provisions for dealing with different mobility cases. Third, we provide a comprehensive set of simulation results that demonstrate the inefficacy of the current standard for handling mobility. Our results show that the ZigBee device plays a significant role in determining the routing performance in mobile scenarios.

关键词： Mobility Routing ZigBee IEEE 802.15.4 simulation

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modeling, systems Engineering, and Project Management for Astronomy IV

Modeling, Systems Engineering, and Project Management for As...

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modeling, systems Engineering, and Project Management for Astronomy IV

ISBN: (纸本)9780819482280

The proceedings contain 64 papers. The topics discussed include: system safety and hazard analysis for the advanced technology solar telescope;optical and system engineering in the development of a high-quality student telescope kit;MUSE instrument global performance analysis;delivered image quality budget for the discovery channel telescope;effects of thermal deformations on the sensitivity of optical systems for space application;investigation of disturbance effects on space-based weak lensing measurements with an integrated model;the Kepler end-to-end model: creating high-fidelity simulations to test Kepler ground processing;introducing atmospheric effects in the numerical simulation of the VLT/MUSE instrument;thermal analysis of the TMT telescope structure;normalized point source sensitivity for off-axis optical performance evaluation of the thirty meter telescope;and analysis of active alignment control of the Hobby-Eberly Telescope wide-field corrector using Shack-Hartmann wavefront sensors.

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An evaluation Study of Mobility Support in ZigBee Networks

An Evaluation Study of Mobility Support in ZigBee Networks

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IFIP International Conference Embedded and Ubiquitous Computing

作者： Chen, Ling-Jyh Sun, Tony Liang, Nia-Chiang Acad Sinica Inst Informat Sci Taipei Taiwan PacketMotion Inc San Jose CA USA Google Inc Mountain View CA USA

关键词： Mobility Routing ZigBee IEEE 802.15.4 simulation

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Parallel performance evaluation of MIC(0) Preconditioning Algorithm for Voxel μFE simulation

Parallel Performance Evaluation of MIC(0) Preconditioning Al...

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8th International Conference, PPAM 2009

作者： Lirkov, Ivan Vutov, Yavor Paprzycki, Marcin Ganzha, Maria Bulgarian Acad Sci Inst Parallel Proc Acad G Bonchev Bl 25A BU-1113 Sofia Bulgaria Polish Acad Sci Syst Res Inst PL-01447 Warsaw Poland

ISBN: (纸本)9783642144028

Numerical homogenization is used for up-scaling of a linear elasticity tensor of strongly heterogeneous micro-structures Utilized approach assumes presence of a periodic micro-structure and thus periodic boundary conditions Rotated trilinear Rannacher-Turek finite elements are used for the discretization while a parallel PCG method is used to solve arising large-scale systems with sparse, symmetric, positive semidefinite matrices Applied preconditioner is based on modified incomplete Cholesky factorization MIC(0) The test problem represents a trabecular bone tissue, and takes into account only the elastic response of the solid phase The voxel micro-structure of the bone is extracted from a high resolution computer tomography image Numerical tests performed on parallel computers demonstrate the efficiency of the developed algorithm

关键词： micro finite element simulation modeling of human bone tissue parallel algorithms PCG method preconditioner MIC(0) factorization parallel performance

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