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IEEE International Symposium on Consumer Electronics (ISCE)

作者： Rong-Jian Chen Wen-Kai Lu Jui-Lin Lai Department of Electronics Engineering National United University Miaoli Taiwan

Architecture design and VLSI implementation of the re-configurable 2-D CAT/ICAT chip for developing the CAT wavelets-based image coding system is presented in this paper. To facilitate the development of this CAT/ICAT chip, we firstly develop the evolution of CA to produce orthogonal 1-D CA bases; then we use the canonical product circuit to produce 2-D CA bases; finally, it utilizes input data and 2-D CA bases to produce 2-D CAT/ICAT coefficients. In order to enhance the flexibility of applications, we developed the re-configurable 2-D CAT/ICAT circuit to make the proposed chip to produce 2-D 4 x 4, 8 x 8, and 16 x 16 CAT/ICAT coefficients. Throughputs of the 2-D 8 x 8, and 16 x 16 CAT/ICAT coefficients are same as that of 2-D 4 x 4 CAT/ICAT coefficients due to the proposed re-configurable 2-D CAT/ICAT chip has highly parallel processing property. We have accomplished the circuit synthesis using the SYNOPSYS tolls with the UMC 0.18 um Cell-library. The chip size was 12.888 mm , and the maximum operation frequency was 111MHz with 851mW total dynamic power. It shows that the architecture of the proposed re-configurable 2-D CAT/ICAT chip is suitable for VLSI realization .

关键词： Very large scale integration image coding image storage Streaming media Fourier transforms Discrete cosine transforms image communication Propagation losses Network servers Web server

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Morphological Enhancement of Medical images in a Logarithmic image Environment

Morphological Enhancement of Medical Images in a Logarithmic...

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International Symposium on signals, Circuits and Systems (ISSCS)

作者： Eugen Zaharescu Mathematics and Informatics Faculty Ovidius University of Constanta Romania

The logarithmic image processing (LIP) theory is a mathematical framework that provides a set of specific algebraic and functional operations and structures that are well adapted to the representation and processing of non-linear images, and more generally of non-linear signals, valued in a bounded intensity range. This very well structured theory determined us to use the logarithmic image representation in our approach for defining a new set of mathematical morphology operators based upon structuring elements with a variable geometrical shape or adaptative structuring elements. The purpose of this paper is to define and to analyze the new multiplicative logarithmic morphological operators used in medical image enhancement. Finally, the experimental results reveal that this method has wide potential areas of impact which may include: Digital x-ray, Digital Mammography, Computer Tomography Scans, Nuclear Magnetic Resonance imagery and Telemedicine applications.

关键词： Biomedical imaging image processing signal processing image representation Morphology Shape image analysis Magnetic analysis image enhancement x-ray imaging

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Medical image Registration via Steerable Pyramid

Medical Image Registration via Steerable Pyramid

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29th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBS 2007), vol.16

作者： x. Wang D. D. Feng School of Information Technologies University of Sydney NSW Australia Center for Multimedia Signal Processing Department of Electronic and Information Engineering Hong Kong Polytechnic University Hong Kong China

image registration is enabling in integrating complementary and heterogeneous information from multiple images, and is particularly important for high-quality healthcare. To improve registration efficiency and accuracy, in this paper, a two-resolution-scale registration approach is proposed. Firstly, to speed up calculation, the images will be decomposed into multi-scale and multi-band representation by steerable pyramid that outweighs wavelets by providing invariance for both translation and rotation. Then, to avoid transformation error accumulation and magnification during the parameter transmission in the traditional multi-scale registration, the registration will be performed only in the lowest-resolution scale and the highest-resolution scale. In the former scale, the global rotation and scaling parameters will be calculated rapidly and accurately, which then will be directly used to initialize optimization in the latter scale, where, the translation differences will be corrected. The experiments on medical images demonstrate that the proposed registration is of good performance.

关键词： Biomedical imaging image registration Medical diagnostic imaging Discrete wavelet transforms Medical services Diseases Australia Information technology Acceleration Frequency

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基于质量一致性优化的视频码率控制

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系统工程与电子技术 2007年第1期29卷 114-117页

作者：唐田野于鸿洋刘钊电子科技大学电子工程学院四川成都610054

针对低码率视频应用,提出一种获得均匀视觉质量的视频码率控制方法。该方法考虑人眼视觉特性,给出一个基于质量一致性优化的模型,并结合视频编码的特点实现此优化模型的求解。应用该方法,可以使图像宏块的量化参数及宏块失真度分布趋于... 详细信息

针对低码率视频应用,提出一种获得均匀视觉质量的视频码率控制方法。该方法考虑人眼视觉特性,给出一个基于质量一致性优化的模型,并结合视频编码的特点实现此优化模型的求解。应用该方法,可以使图像宏块的量化参数及宏块失真度分布趋于集中,从而获得均匀一致的图像质量,同时可以减少编码码流中用于表征宏块间量化参数发生变化的句法比特数,使更多的比特数用于图像净数据的编码,提高编码效率。仿真结果表明,该方法适用于低码率及甚低码率的视频应用。

关键词：信号处理码率控制量化参数视频编码

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Fractional differential analysis for texture of digital image

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JOURNAL OF ALGORITHMS & COMPUTATIONAL TECHNOLOGY 2007年第3期1卷 357-380页

作者： Pu Yi-fei Sichuan Univ Sch Comp Sicence & Technol Chengdu 610064 Sichuan Peoples R China Univ Elect Sci & Technol China Sch Elect Engn Chengdu 610054 Sichuan Peoples R China

This paper discusses the capabilities of the fractional differential approach for the detection of textural features in two-dimensional digital images and the involved Lateral Inhibition Principle, and fractional differential masks and algorithms of digital image. Firstly, the kinetic physical meaning of fractional differential and the relationship between fractional calculus and classical time-frequency analysis and the separability of two-dimensional fractional calculus on certain conditions are deduced. Secondly, the difference between two Gaussians receptive fields for fractional differential of digital image involved signal processing and biologic vision nerve model is discussed. An analysis of its Mach band is also included. Thirdly, the implements and parameters of eight n x n fractional differential masks, which are mutual central symmetric, on negative x-coordinate, positive x-coordinate, negative y-coordinate, positive y-coordinate, left lower diagonal, left upper diagonal, right lower diagonal, right upper diagonal respectively are discussed. Lastly, the numerical implementation algorithms of fractional differential mask for digital image are discussed. Numerical experiments show that the textural details enhance capabilities of fractional differential-based texture operator and are better than that of integral differential based one for rich-grained digital images.

关键词： Fractional order stable coefficient fractional calculus partial fractional differential fractional gradient vector template convolution texture characteristics

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一种新颖的图像多尺度几何变换及其应用

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西安交通大学学报 2007年第8期41卷 982-985页

作者：孙文方宋蓓蓓赵亦工西安电子科技大学电子工程学院西安710071

提出了一种新颖的图像多尺度几何变换方法,主要由预处理、方向滤波器组和最优方向小波变换等组成.方向滤波器组将预处理后的高频分量分解为多个方向子带,然后每个方向子带执行改进的最优方向小波变换.该变换兼有Bandelet变换和Contourle... 详细信息

提出了一种新颖的图像多尺度几何变换方法,主要由预处理、方向滤波器组和最优方向小波变换等组成.方向滤波器组将预处理后的高频分量分解为多个方向子带,然后每个方向子带执行改进的最优方向小波变换.该变换兼有Bandelet变换和Contourlet变换的多尺度几何分析特性,能更稀疏地表示边缘和纹理特征.分别将EBCOT编码和硬阈值去噪应用到图像变换系数中,从而实现了有效的图像压缩和去噪,很好地保护了图像细节.实验结果表明,对于纹理和边缘丰富的图像,所提出的图像压缩和去噪方法在视觉质量上明显优于基于Bandelet或Contourlet变换的方法,峰值信噪比也提高了0.1 dB以上.

关键词：方向小波变换 Contourlet变换 Bandelet变换

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

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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

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实时动态图像压缩技术在弹上产品中的应用

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系统工程与电子技术 2007年第1期29卷 37-40页

作者：李军伟朱振福王楠熊飞目标与环境光学特征国防科技重点实验室

在掌握MPEG4核心技术的基础上,引入完全自创的感兴趣区域内的单象素级运动目标跟踪算法及自适应码率伸缩控制技术,同时配合多媒体数据专业计算平台(BSP-15)进行硬件开发,以适应高速、高压缩率及高保真的要求,其技术成功的应用在某弹上... 详细信息

在掌握MPEG4核心技术的基础上,引入完全自创的感兴趣区域内的单象素级运动目标跟踪算法及自适应码率伸缩控制技术,同时配合多媒体数据专业计算平台(BSP-15)进行硬件开发,以适应高速、高压缩率及高保真的要求,其技术成功的应用在某弹上产品的压缩设备中。对其软硬件设计进行了详细的描述,应用该技术后,此压缩设备能够把分辨率为640×480,高帧频(110 Hz)的电视图像通过1.5 Mbit/s的信道实时传输,压缩比达160∶1以上。

关键词：信号处理图像压缩弹上产品码率控制

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Multiple-Pulse Readout of Linear Silicon Drift Detectors for Fast Imaging applications

Multiple-Pulse Readout of Linear Silicon Drift Detectors for...

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2007 IEEE Nuclear Science Symposium Conference, vol.4

作者： A. Castoldi C. Guazzoni D. Signorelli Sezione di Milano I.N.F.N. Milan Italy Dipartimento di Ingegneria Nucleare Politecnico di Milano Milan Italy Dipartimento di Elettronica e Informazione Politecnico di Milano and INFN Milan Italy STMicroelectronics Castelletto Italy

We discuss the imaging properties of Controlled-Drift Detectors at high photon occupancy that is when the analog waveform at the anode to be readout contains several pulses that may even be partially overlapping. This condition is encountered when the detector is operated in integrate-readout mode at high count rates like in synchrotron experiments. The imaging information, i.e. the incident photon distribution along the column, is still preserved in the waveform and it can be reconstructed by means of a suitable multiple-pulse signal processing. We evaluated multiple-pulse processing based on the weighted least square algorithm in the most relevant operating conditions to assess the achievable resolution of pulse amplitude and position. This analysis allows definition of achievable performances and limitations of Controlled Drift Detectors in high-rate single-photon spectroscopic imaging of x-rays.

关键词： Silicon Detectors High-resolution imaging signal processing algorithms Optical control Anodes Synchrotrons image reconstruction Least squares methods signal resolution

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Application of STAP technique to FMCW systems

Application of STAP technique to FMCW systems

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European Radar Conference (EURAD)

作者： Tomasz Gorski Adam Kawalec Witold Czarnecki Jean-Marc Le Caillec Laurent Lecornu Institute of Radioelectronics Military University of Technology Warszawa Poland Le département Image et Traitement de l'Information GET/Ecole Nationale Supérieure des Télécommunications (ENST) Bretagne Brest France

The fundamental assumption that is made while space-time adaptive processing (STAP) technique is considered is that the signal to be processed takes on the form of a sequence of coherent pulses. Frequency modulated continuous wave (FMCW) systems are in widespread use because of their numerous advantages due among others to its non pulse character. It seems extremely important to look for a possibility of using STAP procedures in FMCW systems to make them even more attractive. The paper presents a simple analysis of a proposed approach to achieve this goal. A structure of the signal processor is presented and assumptions necessary to be fulfilled are defined. Effects of the proposed approach implementation in HF, I, and x bands are evaluated on the basis of selected parameters of the appropriate FMCW-STAP systems.

关键词： signal processing Antenna arrays Low pass filters Mixers Pulse modulation Bandwidth Filtering Radar applications Frequency modulation Mathematical analysis

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