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The Geneva Reduction and Analysis Pipeline for High-contrast Imaging of planetary Companions

MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY 2016年第2期455卷 2178-2186页

作者： Hagelberg, J. Segransan, D. Udry, S. Wildi, F. Univ Hawaii Inst Astron Honolulu HI 96822 USA Univ Geneva Observ Geneva CH-1290 Versoix Switzerland

We present GRAPHIC, a new angular differential imaging reduction pipeline where all geometric image operations are based on Fourier transforms. To achieve this goal the entire pipeline is parallelized making it possible to reduce large amounts of observation data without the need to bin the data. The specific rotation and shift algorithms based on Fourier transforms are described and performance comparison with conventional interpolation algorithm is given. Tests using fake companions injected in real science frames demonstrate the significant gain obtained by using geometric operations based on Fourier transforms compared to conventional interpolation. This also translates in a better point spread function and speckle subtraction with respect to conventional reduction pipelines, achieving detection limits comparable to current best performing pipelines. Flux conservation of the companions is also demonstrated. This pipeline is currently able to reduce science data produced by Very Large Telescope (VLT)/NACO, Gemini/NICI, VLT/SPHERE, and Subaru/SCExAO.

关键词： methods: data analysis techniques: high angular resolution techniques: image processing planets and satellites: detection infrared: planetary systems

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Objective image quality assessment: Facing the real-World challenges 13

Objective image quality assessment: Facing the real-World ch...

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image Quality and System Performance XIII 2016

作者： Wang, Zhou Dept. of Electrical and Computer Engineering University of Waterloo WaterlooON Canada

There has been a growing interest in recent years in the development of objective image quality assessment (IQA) models, whose roles are not only to monitor image quality degradations and benchmark image processing systems, but also to optimize various image and video processing algorithms and systems. While the past achievement is worth celebrating, a number of major challenges remain when we apply existing IQA models in real-world applications. These include obvious ones such as the challenges to largely reduce the complexity of existing IQA algorithms and to make them easy-to-use and easy-to-understand. There are also challenges regarding the applicability of existing IQA models in many real-world problems where image quality needs to be evaluated and compared across dimensionality, across viewing environment, and across the form of representations ? specific examples include quality assessment for image resizing, color-to-gray image conversion, multi-exposure image fusion, image retargeting, and high dynamic range image tone mapping. Here we will first elaborate these challenges, and then concentrate on a specific one, namely the generalization challenge, which we believe is a more fundamental issue in the development, validation and application of IQA models. Specifically, the challenge is about the generalization capability of existing IQA models, which achieve superior quality prediction performance in lab testing environment using a limited number of subject-rated test images, but the performance may not extend to the real-world where we are working with images of a much greater diversity in terms of content and complexity. We will discuss some principle ideas and related work that might help us meet the challenges in the future. © 2016 Society for Imaging Science and Technology.

关键词： image quality

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image stabilization performance: Existing standards and the challenges for mobile imaging 12

Image stabilization performance: Existing standards and the ...

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Digital Photography and Mobile Imaging XII 2016

作者： Artmann, Uwe Feldker, Philipp Image Engineering GmbH and Co KG Frechen Germany

Cameras in mobile phones are supposed to capture images under a huge variety of lighting conditions while mostly hand held. To improve the performance in low light conditions, image stabilization shall optimize the resulting image by reducing the negative effects of motion blur due to handshake. While most cameras use an opto-mechanic approach and correct the motion by moving a lens element or the sensor, other solutions purely rely on algorithms in the signal processing to reduce the motion blur. We evaluate the existing standards, show the challenges and present our efforts in the characterization of an arbitrary stabilization system, including systems based on opto-mechanical components or pure signal processing. © 2016 Society for Imaging Science and Technology.

关键词： Cameras

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Shearlet transform based image denoising using histogram thresholding

Shearlet transform based image denoising using histogram thr...

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2016 International Conference on Communication systems and Networks, ComNet 2016

作者： Anju, T.S. Nelwin Raj, N.R. Department of ECE Sree Chitra Thirunal College of Engineering Pappanamcode Trivandrum Kerala India

ISBN: (纸本)9781509033492

This paper presents an efficient image denoising method by incorporating shearlet-based histogram thresholding. Nowadays, digital images are used in wide range of applications but most of these images are degraded during transmission and acquisition process. Removal of noise from images is still a challenging task for many researchers because there is always a trade-off between noise removal and fine edge preservation. This paper is based on image denoising using shearlet transform. Shearlets have excellent features for data analysis and processing, which overcomes the limitation of traditional methods. They are optimally sparse and have multi-scale and multi-directional properties which are optimal in representing image containing edges. In this paper, the proposed method is found to produce superior peak signal-To-noise ratio (PSNR) over the conventional denoising algorithms. © 2016 IEEE.

关键词： image denoising

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Flood Water Depth Estimation - A Survey

Flood Water Depth Estimation - A Survey

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7th IEEE International Conference on Computational Intelligence and Computing Research (ICCIC)

作者： Nair, Bhavana B. Rao, Sethuraman Amrita Vishwa Vidyapeetham Amrita Ctr Wireless Networks & Applicat Amritapuri Kollam India

ISBN: (纸本)9781509006120

Global warming induced drastic climate changes have increased the frequency of natural disasters such as flooding, worldwide. Flooding is a constant threat to humanity and reliable systems for flood monitoring and analysis need to be developed. Flood hazard assessment needs to take into account physical characteristics such as flood depth, flow velocity and the duration of flooding. This paper provides the researchers with a detailed compilation of the methods that can be used for the estimation of flood water depth. A comparative study has been done between the water depth estimation techniques based on image processing and those which does not involve image processing. The comparison is based on various attributes such as implementation methods, advantages, accuracy and cost. image processing methods are classified based on various algorithms such as character recognition, feature extraction, region of interest (ROI), FIR filter etc. Similarly, non-image processing methods are classified based on hardware used such as sensors, level indicators, etc., and other signal based techniques. This study can be used to identify the best method for flood water depth estimation.

关键词： image processing flood water depth edge detection level indicators sensors

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A Spectral and Spatial Approach of Coarse-to-Fine Blurred image Region Detection

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IEEE SIGNAL processing LETTERS 2016年第11期23卷 1652-1656页

作者： Tang, Chang Wu, Jin Hou, Yonghong Wang, Pichao Li, Wanqing Wuhan Univ Sci & Technol Sch Informat Sci & Engn Wuhan 430081 Peoples R China Tianjin Univ Sch Elect Informat Engn Tianjin 300072 Peoples R China Univ Wollongong Sch Comp & Informat Technol Wollongong NSW 2522 Australia

Blur exists in many digital images, it can be mainly categorized into two classes: defocus blur which is caused by optical imaging systems and motion blur which is caused by the relative motion between camera and scene objects. In this letter, we propose a simple yet effective automatic blurred image region detection method. Based on the observation that blur attenuates high-frequency components of an image, we present a blur metric based on the log averaged spectrum residual to get a coarse blur map. Then, a novel iterative updating mechanism is proposed to refine the blur map from coarse to fine by exploiting the intrinsic relevance of similar neighbor image regions. The proposed iterative updating mechanism can partially resolve the problem of differentiating an in-focus smooth region and a blurred smooth region. In addition, our iterative updating mechanism can be integrated into other image blurred region detection algorithms to refine the final results. Both quantitative and qualitative experimental results demonstrate that our proposed method is more reliable and efficient compared to various state-of-the-art methods.

关键词： Blur blurred region detection gradient distribution region similarity spectrum residual

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FPGA based Hardware Implementation of Automatic Vehicle License Plate Detection System 5

FPGA based Hardware Implementation of Automatic Vehicle Lice...

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International Conference on Advances in Computing, Communications and Informatics (ICACCI)

作者： Chhabra, Surbhi Jain, Himanshu Saini, Sandeep LNM Inst Informat Technol Dept Elect & Commun Engn Jaipur Rajasthan India

ISBN: (纸本)9781509020287

Automatic Vehicle License Plate Detection System (AVLPDS) is the extraction of vehicle license plate information from an image. Besides the safety aspects this system is used in many applications, viz. electronic payment systems, freeway, arterial monitoring systems for traffic surveillance etc. The purpose of this paper is to present the FPGA algorithmic model of most efficient algorithm among three algorithms: Edge-based, Connected-Component based and Histogram based. Each approach is analyzed on the basis of precision and recall rates to determine the success of each approach. After comparison, we can say Histogram based approach has an advantage of being simple and thus faster. Therefore, in this paper, we have used Histogram based Edge processing approach to detect the license plate and presented the FPGA implementation of AVLPDS for the same. The whole system is implemented using MATLAB Simulink and Xilinx System Generator(XSG). Use of XSG for image processing effectively reduces the complexity in structural design and contributes for hardware co-simulation. The accuracy of the algorithm is checked for different sets of input images and significant performance improvement has been found, thereby performing an optimal FPGA-based hardware implementation of AVLPDS.

关键词： Automatic Vehicle License Plate Detection System MATLAB Simulink Xilinx System generator VIVADO HLS FPGA ZedBoard image processing

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Graph Colouring as a Challenge Problem for Dynamic Graph processing on Distributed systems 16

Graph Colouring as a Challenge Problem for Dynamic Graph Pro...

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International Conference on High Performance Computing, Networking, Storage and Analysis (SC)

作者： Sallinen, Scott Iwabuchi, Keita Poudel, Suraj Gokhale, Maya Ripeanu, Matei Pearce, Roger Lawrence Livermore Natl Lab Livermore CA 94550 USA Univ British Columbia Vancouver BC Canada Tokyo Inst Technol Tokyo Japan Univ Alabama Birmingham Birmingham AL USA

ISBN: (纸本)9781467388153

An unprecedented growth in data generation is taking place. Data about larger dynamic systems is being accumulated, capturing finer granularity events, and thus processing requirements are increasingly approaching real-time. To keep up, data-analytics pipelines need to be viable at massive scale, and switch away from static, offline scenarios to support fully online analysis of dynamic systems. This paper uses a challenge problem, graph colouring, to explore massive-scale analytics for dynamic graph processing. We present an event-based infrastructure, and a novel, online, distributed graph colouring algorithm. Our implementation for colouring static graphs, used as a performance baseline, is up to an order of magnitude faster than previous results and handles massive graphs with over 257 billion edges. Our framework supports dynamic graph colouring with performance at large scale better than GraphLab's static analysis. Our experience indicates that online solutions are feasible, and can be more efficient than those based on snapshotting.

关键词： Heuristic algorithms Color image color analysis Algorithm design and analysis Runtime image edge detection Training Algorithm design and analysis Edge detection colored graph image colour analysis Runtime Heuristic algorithms Distributed systems Functional training Color data generation

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Nonlinear SVD-filtering Of Digital images In Infocommunication systems

Nonlinear SVD-filtering Of Digital Images In Infocommunicati...

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10th IEEE International Scientific and Technical Conference on Dynamics of systems, Mechanisms and Machines (Dynamics)

作者： Sazonov, V. V. Shcherbakov, M. A. Vasil'ev, V. A. Penza State Univ Dept Automat & Remote Control Penza Russia

ISBN: (纸本)9781509040490

Feature of modern infocommunication systems is expeditious exchange of information that makes a problem of ensuring quality and reliability of the obtained information actual. For elimination or minimization of the destabilizing impact of noise and hindrances in such systems various methods and algorithms of preliminary information processing are widely used, in particular, procedures of digital filtration of signals and images. Procedure of creation of the nonlinear SVD filter with adaptation to local properties of an observed signal is stated. Comparative examples of filtration of hindrances in a problem of processing of images are given, efficiency of the offered method is shown. The lines of further researches are defined.

关键词： Nonlinear filtering digital image processing Wiener-Kolmogorov filter singular value decomposition of matrices approximation of matrixes

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Extraction of GGO candidate regions from the LIDC database using deep learning 16

Extraction of GGO candidate regions from the LIDC database u...

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16th International Conference on Control, Automation and systems (ICCAS)

作者： Hirayama, Kazuki Tan, Joo Kooi Kim, Hyoungseop Kyushu Inst Technol 1-1 Sensui Kitakyushu Fukuoka 8048550 Japan

ISBN: (纸本)9788993215120

In recent years, development of the computer-aided diagnosis (CAD) systems for the purpose of reducing the false positive on visual screening and improving accuracy of lesion detection has been advanced. Lung cancer is the leading cause of cancer death in the world. Among them, GGO (Ground Glass Opacity) that exhibited early in the before cancer lesion and carcinoma in situ shows a pale concentration, have been concerned about the possibility of undetected on the screening. In this paper, we propose an automatic extraction method of GGO candidate regions from the chest CT image. Our proposed image processing algorithms is consist of four main steps;1) segmentation of volume of interest from the chest CT image and removing the blood vessel regions, bronchus regions based on 3D line filter, 2) first detection of GGO regions based on density and gradient which is selected the initial GGO candidate regions, 3) identification of the final GGO candidate regions based on DCNN (Deep Convolutional Neural Network) algorithms. Finally, we calculates the statistical features for reducing the false-positive (FP) shadow by the rule-based method, performs identification of the final GGO candidate regions by SVM (Support Vector Machine). Our proposed method performed on to the 31 cases of the LIDC (Lung image Database Consortium) database, and final identification performance of TP: 93.02[%], FP: 128.52[/case] are obtained respectively.

关键词： Ground Glass Opacity Computer Aided Diagnosis Lung image Database Consortium Deep Convolutional Neural Network Support Vector Machine

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