检索结果-内蒙古大学图书馆

2007 International Symposium On Signals, Circuits and Systems, ISSCS 2007

作者： Oprisescu, Serban Dragos, Fälie Ciuc, Mihai Buzuloiu, Vasile Image Processing and Analysis Laboratory Faculty of Electronics Telecommunications and Information Technology University Politehnica of Bucharest Romania

ISBN: (纸本)1424409683

The most important characteristic of time-of-flight (ToF) cameras is the ability to measure the distance to each image pixel. Thus, for each pixel, information on both its amplitude and distance to the camera are available. However, technological problems inherent to the acquisition principle lead to inaccuracies in estimating both characteristics: on one hand, there are errors in estimating the distance, especially for far-distance pixels. On the other hand, the detected amplitude decreases with the distance. Part of these inaccuracies are corrected with special camera-calibration software. In this paper, we propose two methods that attempt to further correct each information based on the other one. First, the amplitude image is enhanced by using distance information: a pixel-wise, distance-based correction of the amplitude brings to light details otherwise unnoticeable. Secondly, an amplitude-based distance modification corrects some of the distance estimation errors for far-distance pixels. © 2007 IEEE.

关键词： Pixels

来源：评论

学校读者我要写书评

暂无评论

A Multi-Resolution Mean Field Annealing Algorithm for Motion Estimation in Medical CT image Sequences

A Multi-Resolution Mean Field Annealing Algorithm for Motion...

引用

International Symposium on Signals, Circuits and Systems (ISSCS)

作者： Cristian Grava Vasile Buzuloiu Bertrand Augereau Christine Fernandez-Maloigne Department of Electronics Faculty of Electrical Engineering and Information Technology Oradea Romania Image Processing and Analysis Laboratory Politehnica University of Bucharest Romania Signal Image Communication Laboratory University of Poitiers France

The paper describes a multi-resolution mean field annealing (MFA) algorithm to solve the motion estimation problem in medical image sequences. The proposed algorithm ensures a satisfying trade-off between precision and computational time, in other words, it ensures a good efficiency when compared to other deterministic algorithms and also stochastic ones. The results are compared in terms of precision and computational time with those of other basic algorithms, such as the basic block-matching and Horn & Schunck algorithm. The results are illustrated on CT medical image sequences.

关键词： Annealing Motion estimation Biomedical imaging Computed tomography image sequences Stochastic processes Pixel Equations image motion analysis Laboratories

来源：评论

学校读者我要写书评

暂无评论

An Adaptive Multi-Resolution Algorithm for Motion Estimation in Medical image Sequences

An Adaptive Multi-Resolution Algorithm for Motion Estimation...

引用

European Conference on Circuit Theory and Design, ECCTD

作者： Cristian Grava Adrien Bartoli Jean-Marc Lavest Vincent Gay-Bellile Vasile Buzuloiu Faculty of Electrical Engineering and Information Technology Oradea Romania LASMEA (CNRS/Université Blaise Pascal) Clermont Ferrand France LASMEA CEA Saclay Gif-sur-Yvette France Image Processing and Analysis Laboratory E2809CPolitehnicaE2809D University of Bucharest Romania

We propose an adaptive multi-resolution mean field annealing (MFA) algorithm for motion estimation in medical image sequences. The proposed algorithm can be easily parallelized and therefore is suitable to be implemented on dedicated hardware. The algorithm ensures a trade-off between precision and computational time, i.e. it ensures a good efficiency compared to other deterministic and stochastic algorithms. Results are reported for CT medical image sequences. The results are compared in terms of precision and computational time with those of other algorithms, such as the basic block-matching and Horn & Schunck algorithm, as well as with the mono-resolution and homogeneous multi-resolution MFA algorithm.

关键词： Motion estimation Biomedical imaging image sequences Stochastic processes Equations Medical diagnostic imaging Multiresolution analysis Pixel Computational efficiency Design for disassembly

来源：评论

学校读者我要写书评

暂无评论

Fuzzy color-based semantic characterization of animation movies

Fuzzy color-based semantic characterization of animation mov...

引用

作者： Ionescu, Bogdan Lambert, Patrick Coquin, Didier Buzuloiu, Vasile Image Processing and Analysis Laboratory University Politehnica of Bucharest Romania Laboratoire d'Informatique Systemes Traitement de l'Information et de la Connaissance Universite de Savoie Annecy France

ISBN: (纸本)0892082623

In this paper a fuzzy statistical color-based approach for semantic characterization of animation movies is proposed. Color is a major feature of animation movies: each movie has its own color distribution. Deriving semantic information about the used color artistry concepts or about the sensation induced by the movie's color distribution should be an ideal analysis-tool for the animation experts. First, the movie is divided into shots and a movie abstract is then automatically generated. Color reduction is applied on each retained frame using an error diffusion algorithm with a predefined color palette. Then, a global weighted color histogram of the movie is computed by taking into account each shot relevance. It serves as a basis of computation for relevant color-based statistics, such as the elementary colors distribution or the light/dark color ratios. Using a fuzzy representation, meaningful color-based semantic information is then derived from the obtained parameters, namely: light-dark contrast, cold-warm contrast and contrast of saturation schemes, the color variations/diversity and the adjacent/complementary colors. The proposed approach was tested on several animation movies.

关键词： Animation

来源：评论

学校读者我要写书评

暂无评论

LANDING AN UNMANNED AIR VEHICLE: VISION BASED MOTION ESTIMATION AND NONLINEAR CONTROL

引用

Asian Journal of Control 2008年第3期1卷

作者： Omid Shakernia Yi Ma T. John Koo Shankar Sastry Dept. of Electrical Engineering & Computer Science University of California at Berkeley Berkeley CA94720-1774 U.S.A. Tak-Kuen John Koo received the B.Eng. degree in 1992 in Electronic Engineering and the M.Phil. in 1994 in Information Engineering both from the Chinese University of Hong Kong. From 1994 to 1995 he was a graduate student in Signal and Image Processing Institute at the University of Southern California. He is currently a Ph.D. Candidate in Electrical Engineering and Computer Sciences at the University of California at Berkeley. His research interests include nonlinear control theory hybrid systems inertial navigation systems with applications to unmanned aerial vehicles. He received the Distinguished M.Phil. Thesis Award of the Faculty of Engineering The Chinese University of Hong Kong in 1994. He was a consultant of SRI International in 1998. Currently he is the team leader of the Berkeley AeRobot Team and a delegate of The Graduate Assembly University of California at Berkeley. He is a student member of IEEE and SIAM. S. Shankar Sastry received his Ph.D. degree in 1981 from the University of California Berkeley. He was on the faculty of MIT from 1980-82 and Harvard University as a Gordon McKay professor in 1994. He is currently a Professor of Electrical Engineering and Computer Sciences and Bioengineering and Director of the Electronics Research Laboratory at Berkeley. He has held visiting appointments at the Australian National University Canberra the University of Rome Scuola Normale and University of Pisa the CNRS laboratory LAAS in Toulouse (poste rouge) and as a Vinton Hayes Visiting fellow at the Center for Intelligent Control Systems at MIT. His areas of research are nonlinear and adaptive control robotic telesurgery control of hybrid systems and biological motor control. He is a coauthor (with M. Bodson) of “Adaptive Control: Stability Convergence and Robustness Prentice Hall 1989.” and (with R. Murray and Z. Li) of “A Mathematical Introduction to Robotic Manipulati

In this paper, we use computer vision as a feedback sensor in a control loop for landing an unmanned air vehicle (UAV) on a landing pad. The vision problem we address here is then a special case of the classic ego-motion estimation problem since all feature points lie on a planar surface (the landing pad). We study together the discrete and differential versions of the ego-motion estimation, in order to obtain both position and velocity of the UAV relative to the landing pad. After briefly reviewing existing algorithm for the discrete case, we present, in a unified geometric framework, a new estimation scheme for solving the differential case. We further show how the obtained algorithms enable the vision sensor to be placed in the feedback loop as a state observer for landing control. These algorithms are linear, numerically robust, and computationally inexpensive hence suitable for real-time implementation. We present a thorough performance evaluation of the motion estimation algorithms under varying levels of image measurement noise, altitudes of the camera above the landing pad, and different camera motions relative to the landing pad. A landing controller is then designed for a full dynamic model of the UAV. Using geometric nonlinear control theory, the dynamics of the UAV are decoupled into an inner system and outer system. The proposed control scheme is then based on the differential flatness of the outer system. For the overall closed-loop system, conditions are provided under which exponential stability can be guaranteed. In the closed-loop system, the controller is tightly coupled with the vision based state estimation and the only auxiliary sensor are accelerometers for measuring acceleration of the UAV. Finally, we show through simulation results that the designed vision-in-the-loop controller generates stable landing maneuvers even for large levels of image measurement noise. Experiments on a real UAV will be presented in future work.

关键词： Motion estimation computer vision based control unmanned air vehicle differential flatness

来源：评论

学校读者我要写书评

暂无评论

Temporal Enhancement And Color Based Motion Detection In image Sequences

Temporal Enhancement And Color Based Motion Detection In Ima...

引用

International Conference on Optimization of Electrical and Electronic Equipment, OPTIM

作者： C. Vertan V. Buzuloiu Image Processing and Analysis Laboratory Applied Electronics and Information Engineering Department Faculty of Electronics and Telecommunications Bucharest Politehnica University Bucharest Romania

来源：评论

学校读者我要写书评

暂无评论

A Family Of Order Statistic Based Dissimilarity Measures And Their Application In image processing

A Family Of Order Statistic Based Dissimilarity Measures And...

引用

International Conference on Optimization of Electrical and Electronic Equipment, OPTIM

作者： C. Vertan V. Buzuloiu R.M. Rangayyan Image Processing and Analysis Laboratory (IPAL) Applied Electronics and Information Engineering DepartmentFaculty of Electronics and Telecommunications Politehnica University Bucharest Romania Department of Electrical and Computer Engineering University of Calgary Calgary AB Canada

来源：评论

学校读者我要写书评

暂无评论

A high-speed high-density array-multiplier-accumulator for digital signal processing

引用

ELECTRONICS AND COMMUNICATIONS IN JAPAN PART II-ELECTRONICS 1996年第2期79卷 86-97页

作者： Minami, T Kasai, R Matsuda, H Kusaba, R Member NTT LSI Laboratories Atsugi Japan 243-01 Graduated in 1980 from the Department of Electrical Engineering Kyushu University where he received his Master's degree in 1982 and joined NTT. Until March 1986 he was engaged in the development of application software for electronic switching systems. He then engaged in research and development of LSIs for image signal processing. At present he is Senior Research Engineer Advanced LSI Laboratory NTT LSI Laboratories. He is a member of IEEE. Graduated in 1972 from the Department of Electrical Engineering Osaka University where he received his Master's degree in 1974 and his Ph.D. in 1992. He joined NTT in 1974. He is engaged in research and development of analysis of MOS devices and design of ASIC for communication. At present he is Executive Research Engineer Advanced LSI Laboratory NTT LSI Laboratories. He is a member of IEEE. Graduated in 1987 from the Department of Communications Tohoku University where he received his Master's degree in 1989 and joined NTT. He is engaged in research and development of high-speed design for image processing LSIs. At present he is Research Engineer Advanced LSI Laboratory NTT LSI Laboratories. He is a member of the Information Processing Society. Graduated in 1985 from the Department of Electrical Engineering Keio University where he received his Master's degree in 1987 and joined NTT. He is engaged in CAD research. At present he is Senior Research Engineer Advanced LSI Laboratory NTT LSI Laboratories. He is a member of the Information Processing Society and IEEE.

This paper discusses the downsizing and speed improvement of short-word multiplier-accumulators, which are frequently used in digital signal processors. As a first step, the optimal configuration for an array-type carry-save adder is considered where the shortest path in the full-adder is used to propagate the sum signal and the carry signal is sent to the full-adder of the two lower stages by skipping a stage. A configuration of the full-adder suitable for the structure is proposed. The case of eight partial product additions shows that the delay can be reduced by 22 percent compared to a simple array-type carry-save adder. Then the short-word carry look-ahead adder using the pass-transistor logic is considered. It is shown that a single-stage carry look-ahead circuit with a four-bitwise iterative structure exhibits nearly the same delay as a two-stage carry look-ahead circuit. In other words, the former is better suited to downsizing. This paper intends to examine the effectiveness of the foregoing new array-type carry-save adder and the single-stage carry look-ahead circuit using the 0.5-mu m CMOS technology. A 16-bit x 14-bit + 31-bit multiplier-accumulator has been designed and is evaluated for cases where the array-type carry-save adder is used to handle accumulation as well as partial products. The resulting area and delay are 0.77 x 0.78 mm(2) and 6.8 ns, respectively. The effectiveness of the approach used in this paper is evaluated by constructing a multiplier-accumulator, but the method is also useful in constructing a multiplier.

关键词： product-sum operation array multiplier carry-save adder full-adder carry look-ahead adder

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：