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Conference on Satellite Data Compression, Communications, and Archiving iii

作者： Gladkova, Irina Gottipati, Srikanth Grossberg, Michael CCNY NOAA CREST New York NY 10031 USA

ISBN: (纸本)9780819468314

Multispectral imaging is becoming an increasingly important tool for monitoring the earth and its environment from space borne and airborne platforms. Multispectral imaging data consists of visible and IR measurements from a scene across space and spectrum. Growing data rates resulting from faster scanning and finer spatial and spectral resolution makes compression an increasingly critical tool to reduce data volume for transmission and archiving. Examples of multispectral sensors we consider include the NASA 36 band MODIS imager, Meteosat 2nd generation 12 band SEVIRI imager, GOES R series 16 band ABI imager, current generation GOES 5 band imager, and Japan's 5 band MTSAT imager. Conventional lossless compression algorithms are not able to reach satisfactory compression ratios nor are they near the upper limits for lossless compression on imager data as estimated from the Shannon entropy. We introduce a new lossless compression algorithm developed for the NOAA-NESDIS satellite based Earth science multispectral imagers. The algorithm is based on capturing spectral correlations using spectral prediction, and spatial correlations with a linear transform encoder. The algorithm as presented has been designed to work with NOAA's scientific data and so is purely lossless but lossy modes can be supported. The compression algorithm also structures the data in a way that makes it easy to incorporate robust error correction using FEC coding methods as TPC and LDPC for satellite use. This research was funded by NOAA-NESDIS for its Earth observing satellite program and NOAA goals.

关键词： Image compression imaging systems Sensors MODIS Satellites Algorithm development JPEG2000 Image processing Satellite imaging Earth sciences

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Endovascular Navigation of a Ferromagnetic Microrobot Using MRI-based Predictive Control

Endovascular Navigation of a Ferromagnetic Microrobot Using ...

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IEEE/RSJ International Conference on Intelligent Robots and systems

作者： Belharet, Karim Folio, David Ferreira, Antoine Inst PRISME EA 4229 F-18020 Bourges France

ISBN: (纸本)9781424466757

This paper presents real-time MRI-based control of a ferromagnetic microcapsule for endovascular navigation. The concept was studied for future development of microdevices designed to perform minimally invasive interventions in remote sites accessible through the human cardiovascular system. A system software architecture is presented illustrating the different software modules to allow navigation of a microdevice in blood vessels, namely: (i) vessel path planner, (ii) magnetic gradient steering, (iii) tracking and (iv) closed-loop navigation control. First, the position recognition of the microrobot into the blood vessel is extracted using Frangi vesselness filtering from the pre-operation images. Then, a set of minimal trajectory is predefined, using FMM, to guide the microrobot from the injection point to the tumor area through the anarchic vessel network. Based on the pre-computed path, a GPC is proposed for robust time-multiplexed navigation along a 2D path in presence of pulsative flow. The simulation results suggest the validation of the proposed image processing and control algorithms. A series of disturbances introduced in the presence and absence of closed-loop control affirms the robustness and effectiveness of this predictive control system.

关键词： Frangi vesselness filtering GPC MRI-based predictive control anarchic vessel network biomedical MRI blood vessel blood vessels cardiovascular system closed loop systems closed-loop navigation control endovascular navigation ferromagnetic microcapsule ferromagnetic microrobot ferromagnetism human cardiovascular system image processing magnetic gradient steering magnetic resonance imaging medical image processing medical robotics microdevice microrobots path planning pose estimation position recognition predictive control preoperation image pulsatile flow pulsative flow remote site software architecture telerobotics time-multiplexed navigation tumor tumours vessel path planner

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Extraction of text lines and text blocks on document images based on statistical modeling

Extraction of text lines and text blocks on document images ...

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3rd Conference on Document Recognition

作者： Chen, S Haralick, RM Phillips, IT CAERE CORP LOS GATOSCA 95030

ISBN: (纸本)0819420344

In this paper, we developed statistical models to characterize the text line and text block structures on document images using the text word bounding boxes. We posed the extraction problem as finding the text lines and text blocks that maximize the Bayesian probability of the text lines and text blocks by observing the text word bounding boxes. We derived the so-called probabilistic linear displacement model (PLDM) to model the text line structures from text word bounding boxes. We also developed an augmented PLDM model to characterize the text block structures from text line bounding boxes. By systematically gathering statistics from a large population of document images, we are able to validate our models experimentally and determine the proper model parameters. We designed and implemented an iterative algorithm that utilized these probabilistic models to extract the text lines and text blocks. The quantitative performances of the algorithm in terms of the rates of miss, false, correct, splitting, merging and spurious detections of the text lines and text blocks were reported.

关键词： Detection and tracking algorithms Statistical analysis Astatine Binary data Statistical modeling Algorithm development Palladium Performance modeling Image processing algorithms and systems Image segmentation

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Storm System Database: A Big Data Approach to Moving Object Databases

Storm System Database: A Big Data Approach to Moving Object ...

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4th International Conference on Computing for Geospatial Research and Application (COM.Geo)

作者： Olsen, Brian McKenney, Mark So Illinois Univ Dept Comp Sci Edwardsville IL 62026 USA

ISBN: (纸本)9780769550121

Rainfall data is often collected by measuring the amount of precipitation collected in a physical container at a site. Such methods provide precise data for those sites, but are limited in granularity to the number and placement of collection devices. We use radar images of storm systems that are publicly available and provide rainfall estimates for large regions of the globe, but at the cost of loss of precision. We present a moving object database called Storm DB that stores decibel measurements of rain clouds as moving regions, ie., we store a single rain cloud as a region that changes shape and position over time. Storm DB is a prototype system that answers rain amount queries over a user defined time duration for any point in the continental United States. In other words, a user can ask the database for the amount of rainfall that fell at any point in the US over a specified time window. Although this single query seems straightforward, it is complicated due to the expected size of the dataset: storm clouds are numerous, radar images are available in high resolution, and our system will collect data over a large timeframe;thus, we expect the number and size of moving regions representing storm clouds to be large. To implement our proposed query, we bring together the following concepts: (i) image processing to retrieve storm clouds from radar images, (ii) interpolation mechanisms to construct moving regions with infinite temporal resolution from region snapshots, (iii) transformations to compute exact point in moving polygon queries using 2-dimensional rather than 3-dimensional algorithms, (iv) GPU algorithms for massively parallel computation of the duration that a point lies inside a moving polygon, and (v) map/reduce algorithms to provide scalability. The resulting prototype lays the groundwork for building big data solutions for moving object databases.

关键词： graphics processing units image processing query processing radar imaging visual databases

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Frequency response and distortion properties of nonlinear image processing algorithms and the importance of imaging context

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MEDICAL PHYSICS 2013年第9期40卷 091906-091906页

作者： Wells, Jered R. Dobbins, James T., iii Duke Univ Med Ctr Carl E Ravin Adv Imaging Labs Durham NC 27705 USA Duke Univ Med Phys Grad Program Durham NC 27705 USA Duke Univ Dept Radiol Med Ctr Durham NC 27710 USA Duke Univ Dept Biomed Engn Durham NC 27708 USA Duke Univ Dept Phys Durham NC 27708 USA

Purpose: The most common metrics for resolution analysis in medical imaging are valid only for (approximately) linear systems. While analogues to these metrics have been used in attempts to describe resolution performance in nonlinear systems, the analysis is incomplete since distortion effects are often ignored. The authors have developed a methodology to analyze the amplitude modulation and waveform distortion properties of nonlinear systems with specific application to medical image processing algorithms. Methods: Using sinusoidal basis functions, two metrics were derived which distinguish amplitude modulation from nonlinear waveform distortion: principle frequency response and distortion power spectrum, respectively. Additionally, two figures of merit were developed to describe the relative impact of nonlinear distortion as a result of image processing: distortion index (DI) and Sigma DI. Three nonlinear denoising algorithms, the median, bilateral, and wavelet denoising filters, were selected as example functions to demonstrate the utility of the metrics derived in this study. Results: Each filter showed very different resolution and waveform distortion properties. In particular, the amplitude and extent of nonlinear distortion depended strongly on image context and the type of nonlinear mechanism employed. Nonlinear waveform distortion constituted up to 30% of the median filter output signal power in high contrast-to-noise ratio (CNR) scenarios. Conversely, nonlinear distortion never exceeded 1% of the bilateral filter output signal power. The wavelet denoising response contained between 1% and 9% distortion which varied weakly as a function of CNR. Conclusions: The analytical metrics described in the paper demonstrate the importance of considering both resolution-and distortion-related effects in characterizing the performance of nonlinear imaging systems with specific application to image processing algorithms. Findings with three common nonlinear algorithms

关键词： frequency response nonlinear resolution total harmonic distortion image processing algorithms

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Occlusion processing and smooth surface shading for fully computed synthetic holography

Occlusion processing and smooth surface shading for fully co...

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Conference on Practical Holography XI and Holographic Materials iii

作者： Underkoffler, J MIT Media Lab. (United States)

ISBN: (纸本)0819424226

Computation for synthetic holography typically takes one of two forms: the 'stereogram' approach, in which a large number of two-dimensional perspective views are rendered and assembled into a composite fringe pattern;and the 'fully computed' approach, in which the physics of light propagation from geometric surfaces and the resulting interference patterns at a recording plane are all simulated. algorithms implementing the stereogram approach often generate their component perspective views by taking advantage of dedicated graphics hardware, capable of rapid rendering with hidden-surface removal and smooth shading. However, these standard computer graphics schemes for occlusion and shading art inappropriate for fully computed hologram synthesis. We describe an efficient algorithm chat starts with a standard-form geometric description of the desired scene and generates a list of simple holographic 'primitives' that can be transformed into the final interference pattern by a simple fringe rendering program. The algorithm simultaneously performs the multiple-viewpoint: equivalent of hidden surface removal, so that nearer surfaces and objects properly occlude those more distant, and surface shading, so that each object appears solid and exhibits the correct visual behavior in response to lighting in the scene.

关键词： Holography Computing systems Fringe analysis Holograms Computer graphics Diffraction Stereo holograms Computer simulations Optical simulations Visualization

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Semantics and image content integration for pulmonary nodule interpretation in thoracic computed tomography

Semantics and image content integration for pulmonary nodule...

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Medical imaging 2007 Conference

作者： Raicu, Daniela S. Varutbangkul, Ekarin Cisneros, Janie G. Furst, Jacob D. Channin, David S. Armato, Samuel G., iii Depaul Univ Intelligent Multimedia Proc Lab Sch Comp Sci Telecommun & Informat Syst Chicago IL 60604 USA Northwestern Univ Med Sch Dept Radiol Chicago IL 60611 USA Univ Chicago Dept Radiol Chicago IL 60637 USA

ISBN: (纸本)9780819466303

Useful diagnosis of lung lesions in computed tomography (CT) depends on many factors including the ability of radiologists to detect and correctly interpret the lesions. Computer-aided Diagnosis (CAD) systems can be used to increase the accuracy of radiologists in this task. CAD systems are, however, trained against ground truth and the mechanisms employed by the CAD algorithms may be distinctly different from the visual perception and analysis tasks of the radiologist. In this paper, we present a framework for finding the mappings between human descriptions and characteristics and computed image features. The data in our study were generated from 29 thoracic CT scans collected by the Lung Image Database Consortium (LIDC). Every case was annotated by up to 4 radiologists by marking the contour of nodules and assigning nine semantic terms to each identified nodule;fifty-nine image features were extracted from each segmented nodule. Correlation analysis and stepwise multiple regression were applied to find correlations among semantic characteristics and image features and to generate prediction models for each characteristic based on image features. From our preliminary experimental results, we found high correlations between different semantic terms (margin, texture), and promising mappings from image features to certain semantic terms (texture, lobulation, spiculation, malignancy). While the framework is presented with respect to the interpretation of pulmonary nodules in CT images, it can be easily extended to find mappings for other modalities in other anatomical structures and for other image features.

关键词： LIDC shape texture stepwise multiple regression correlation analysis

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Polyp segmentation in NBI colonoscopy

Polyp segmentation in NBI colonoscopy

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Workshops Bildverarbeitung fur die Medizin: Algorithmen - Systeme - Anwendungen, BVM 2009 - Workshop on Image processing for Medicine: algorithms - systems - Applications, BVM 2009

作者： Gross, Sebastian Kennel, Manuel Stehle, Thomas Wulff, Jonas Tischendorf, Jens Trautwein, Christian Aach, Til Institute of Imaging and Computer Vision RWTH Aachen University Germany Medical Department III RWTH Aachen University Hospital Germany

ISBN: (纸本)9783540938590

Endoscopic screening of the colon (colonoscopy) is performed to prevent cancer and to support therapy. During intervention colon polyps are located, inspected and, if need be, removed by the investigator. We propose a segmentation algorithm as a part of an automatic polyp classification system for colonoscopic Narrow-Band images. Our approach includes multi-scale filtering for noise reduction, suppression of small blood vessels, and enhancement of major edges. Results of the subsequent edge detection are compared to a set of elliptic templates and evaluated. We validated our algorithm on our polyp database with images acquired during routine colonoscopic examinations. The presented results show the reliable segmentation performance of our method and its robustness to image variations.

关键词： Blood vessels

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IMAGE SCREENING USING SPATIAL FILTERS BASED ON LINEAR TRANSFORMATION FOR IMAGE RECOGNITION

IMAGE SCREENING USING SPATIAL FILTERS BASED ON LINEAR TRANSF...

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3rd Annual SPIE Conference on Machine Vision Applications in Industrial Inspection

作者： ARIMURA, K HAGITA, N NIPPON TELEGRAPH & TEL PUBL CORP BASIC RES LABS ATSUGI KANAGAWA 14301 JAPAN

ISBN: (纸本)081941770X

Statistical image recognition methods based on linear transformation require a lot of calculation of correlation between subimages and reference patterns of the specified objects to be detected. Image screening provides an effective preprocessing method for lowering the calculation load and improving recognition accuracy. It selects candidate subimages that are similar to the detecting objects in images and rejects the remainders using spatial filters which are based on linear transformation. We have already investigated the spatial filters that are based on 2D projection pursuit (PP). PP requires more heavy calculation load than the principal components analysis (PCA). We, therefore, compare spatial filters based on two kinds of linear transformation algorithms, the PP and PCA, in terms of recognition accuracy and efficiency. Experiments are made for two object detection tasks: eye- and mouth-area detection in face images and text-area detection in document images. The results show that PCA-based image screening is superior to PP-based one for the eye- and mouth-area detection. PCA also achieves higher recognition rate (75%) than PP for the eye- and mouth-area detection, while PP offers equal performance in text-area detection. The results suggest that PCA is totally superior to PP in image screening.

关键词： Principal component analysis Spatial filters Detection and tracking algorithms Tolerancing Image filtering Eye Facial recognition systems Image processing Mouth Error analysis

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Two- and three-dimensional quantitative image analysis of coronary arteries from hi-resolution histological sections

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Proceedings of SPIE - The International Society for Optical Engineering 2000年 3911卷 69-74页

作者： Holmes iii, David R. Robb, Richard Mayo Foundation Rochester United States

The study of coronary arteries has evolved from examining gross anatomy and morphology to scrutinizing micro-anatomy and cellular composition. Technological advances such as high-powered digital microscopes and high precision cutting devices have allowed clinicians to examine coronary artery morphology and pathology at micron resolution. Our work explores the composition of normal coronary arteries in order to provide the foundation for further study of remodeled tissue. The first of two coronary arteries was sliced into 442 sections with 4 micron inter-slice spacing. Each slice was stained for elastin and collagen. The second coronary artery was sectioned into 283 slices, also with 4 micron resolution. These slices were stained for cellular nuclei and smooth muscle. High resolution light microscopy was used to image the sections. The data was analyzed for collegen/elastin content and nuclei density, respectively. processing of this type of data is challenging in the areas of segmentation, visualization and quantification. Segmentation was confounded by variation in image quality as well as complexity of the coronary tissue. These problems were overcome by the development of 'smart' thresholding algorithms for segmentation. In addition, morphology and image statistics were used to further refine the results of the segmentation. Specificity/sensitivity analysis suggests that automatic segmentation can be very effective. 3-D visualization of coronary arteries is challenging due to multiple tissue layers. Methods such as summed voxel projection and maximum intensity projection appear to be effective. Shading methods also provide adequate visualization, however it is important to incorporate combined 2-D and 3-D displays. Surface rendering techniques (e.g. texture mapping) are useful tools for visualizing parametric data. Quantification in three dimensions is simple in practice but appropriate descriptions of these results must be displayed to clinicians in a clear way.

关键词： Medical imaging

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