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Long Term Safety Area Tracking (LT-SAT) with online failure detection and recovery for robotic minimally invasive surgery

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MEDICAL image ANALYSIS 2018年 45卷 13-23页

作者： Penza, Veronica Du, Xiaofei Stoyanov, Danail Forgione, Antonello Mattos, Leonardo S. De Momi, Elena Politecn Milan Dept Elect Informat & Bioengn Pzza L Da Vinci 32 I-20133 Milan Italy Ist Italiano Tecnol Dept Adv Robot Via Morego 30 I-16163 Genoa Italy UCL Ctr Med Image Comp Dept Comp Sci London England Osped Niguarda Ca Granda Pzza Osped Maggiore 3 I-20162 Milan Italy

Despite the benefits introduced by robotic systems in abdominal Minimally Invasive Surgery (MIS), major complications can still affect the outcome of the procedure, such as intra-operative bleeding. One of the causes is attributed to accidental damages to arteries or veins by the surgical tools, and some of the possible risk factors are related to the lack of sub-surface visibilty. Assistive tools guiding the surgical gestures to prevent these kind of injuries would represent a relevant step towards safer clinical procedures. However, it is still challenging to develop computer vision systems able to fulfill the main requirements: (i) long term robustness, (ii) adaptation to environment/object variation and (iii) real time processing. The purpose of this paper is to develop computer vision algorithms to robustly track soft tissue areas (Safety Area, SA), defined intra-operatively by the surgeon based on the real-time endoscopic images, or registered from a pre-operative surgical plan. We propose a framework to combine an optical flow algorithm with a tracking-by-detection approach in order to be robust against failures caused by: (i) partial occlusion, (ii) total occlusion, (iii) SA out of the field of view, (iv) deformation, (v) illumination changes, (vi) abrupt camera motion, (vii), blur and (viii) smoke. A Bayesian inference-based approach is used to detect the failure of the tracker, based on online context information. A Model Update Strategy (MUpS) is also proposed to improve the SA re-detection after failures, taking into account the changes of appearance of the SA model due to contact with instruments or image noise. The performance of the algorithm was assessed on two datasets, representing ex-vivo organs and in-vivo surgical scenarios. Results show that the proposed framework, enhanced with MUpS, is capable of maintain high tracking performance for extended periods of time (similar or equal to 4 min - containing the aforementioned events) with high precisi

关键词： Long-term tissue tracking Tracking failure detection Model Update Strategy Robotic minimally invasive surgery

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VIMOS - Autonomous image analysis on board of BIROS

VIMOS - Autonomous image analysis on board of BIROS

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19th IFAC Symposium on Automatic Control in Aerospace, ACA 2013

作者： Goetz, Katharina A.M. Huber, Felix Von Schoenermark, Maria German Aerospace Center 82234 Weßling Germany

ISBN: (纸本)9783902823465

Some events on the Earth's surface require a fast and well coordinated reaction, such as disasters like earthquakes, oods, the occurrence of drifting icebergs or illegal activities like piracy or cleaning of oil tankers polluting the sea. Field help and prompt intervention can be supported by the examination of images recently acquired by Earth observing satellites. The extraction of useful information out of image data in real-time directly on board a spacecraft can shorten the timespan between image acquisition and an appropriate reaction drastically. This is one of two major aspects of image analysis on board a satellite. Secondly, if the amount of unusable data and/or the degree of cloudiness of a currently acquired scene is known on board, affected images can be (partially) discarded, which leads to an optimized usage of storage and downlink capacity. VIMOS will be a collection of image processing and remote sensing algorithms, running as an experiment on board of the German satellite BIROS. The purpose of VIMOS is a first demonstration of algorithms applied to data of optical sensors, dedicated to an operation on board a satellite, like e.g. cloud detection, change detection and object recognition. VIMOS will be able to send a trigger message to the autonomous on board mission planning unit, which can check possibly modiffed conditions on board, and react accordingly e.g. by planning a new timeline. © IFAC.

关键词： Satellites

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Automatic class labeling of classified imagery using a hyperspectral library

Automatic class labeling of classified imagery using a hyper...

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作者： Parshakov, Ilia University of Lethbridge

学位级别：master

image classification is a fundamental information extraction procedure in remote sensing that is used in land-cover and land-use mapping. Despite being considered as a replacement for manual mapping, it still requires some degree of analyst intervention. This makes the process of image classification time consuming, subjective, and error prone. For example, in unsupervised classification, pixels are automatically grouped into classes, but the user has to manually label the classes as one land-cover type or another. As a general rule, the larger the number of classes, the more difficult it is to assign meaningful class labels. A fully automated post-classification procedure for class labeling was developed in an attempt to alleviate this problem. It labels spectral classes by matching their spectral characteristics with reference spectra. A Landsat TM image of an agricultural area was used for performance assessment. The algorithm was used to label a 20- and 100-class image generated by the ISODATA classifier. The 20-class image was used to compare the technique with the traditional manual labeling of classes, and the 100-class image was used to compare it with the Spectral Angle Mapper and Maximum Likelihood classifiers. The proposed technique produced a map that had an overall accuracy of 51%, outperforming the manual labeling (40% to 45% accuracy, depending on the analyst performing the labeling) and the Spectral Angle Mapper classifier (39%), but underperformed compared to the Maximum Likelihood technique (53% to 63%). The newly developed class-labeling algorithm provided better results for alfalfa, beans, corn, grass and sugar beet, whereas canola, corn, fallow, flax, potato, and wheat were identified with similar or lower accuracy, depending on the classifier it was compared with.%%%%vii, 93 leaves : ill., maps (some col.) ; 29 cm

关键词： Remote-sensing images ?– Data processing image processing ?– Digital techniques Pattern recognition systems algorithms image analysis ?– Mathematics image analysis ?– Data processing Dissertations Academic

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image-based driver's guidance system 20

Image-based driver's guidance system

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20th ISPRS Congress on Technical Commission vii

作者： Tóth, Z. Lovas, T. Mélykúti, G. Barsi, Á. Department of Photogrammetry and Geoinformatics Budapest University of Technology and Economics Muegyetem rkp.3 BudapestH-1111 Hungary

The paper presents a low-cost navigation system, which is based on digital terrestrial images. The database of the test area is filled by digital images about road junctions, crossings, and other "irregularities taken with a high-resolution commercial camera. The developed guidance system solves the usual problem within urban circumstances (one or two way streets etc.), which is followed by a systematic image query along the found optimal path. The queried images of the database are extended by simple navigational instructions (arrows) to give visual information for the driver. The obtained image-based itinerary contains more information than the widely used navigation systems, and allows better navigation performance in unknown situations. The paper gives an overview about the planning of the field works, the execution of data acquisition by GPS and photography, as well as the database built-up and how the whole data set is structured and stored. It is followed by the presentation of the implemented algorithms. The use of the developed system is shown on an example executed in Budapest, Hungary. © 2018 International Society for Photogrammetry and Remote Sensing. All rights reserved.

关键词： Query processing

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Improved successive refinement for wavelet-based embedded image compression

Improved successive refinement for wavelet-based embedded im...

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Proceedings of the 1999 Wavelet Applications in Signal and image processing vii

作者： Creusere, Charles D. Naval Air Warfare Cent China Lake United States

In this paper we consider a new form of successive coefficient refinement which can be used in conjunction with embedded compression algorithms like Shapiro's EZW (Embedded Zerotree Wavelet) and Said & Pearlman's SPIHT (Set Partitioning in Hierarchical Trees). Using the conventional refinement process, the approximation of a coefficient that was earlier determined to be significant is refined by transmitting one of two symbols - an 'up' symbol if the actual coefficient value is in the top half of the current uncertainty interval or a 'down' symbol if it is in the bottom half. In the modified scheme developed here, we transmit one of 3 symbols instead - 'up', 'down', or 'exact'. The new 'exact' symbol tells the decoder that its current approximation of a wavelet coefficient is 'exact' to the level of precision desired. By applying this scheme in earlier work to lossless embedded compression (also called lossy/lossless compression), we achieved significant reductions in encoder and decoder execution times with no adverse impact on compression efficiency. These excellent results for lossless systems have inspired us to adapt this refinement approach to lossy embedded compression. Unfortunately, the results we have achieved thus far for lossy compression are not as good.

关键词： Wavelet transforms

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THE AUTOMATION OF THE PROCESS OF LAND AREA CHANGE DETECTION IN PERMANENT MONITORING systems

THE AUTOMATION OF THE PROCESS OF LAND AREA CHANGE DETECTION ...

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ISPRS Geospatial Week

作者： Areshkina, L. V. Belazerskii, L. A. Oreshkin, N. United Inst Informat Problems United Inst NAS Minsk 220012 BELARUS Artec Grp L-1466 Luxembourg Luxembourg

ISBN: (纸本)9781629935201

A new automation process for change detection of land area is proposed. The method is based on the use of multitemporal satellite images and their histograms. The proposed discrete representation of land area in small image fragments makes it possible to detect changes automatically within each fragment. This method provides improvements of change detection accuracy and simplifies the software realization by unifying recursively performed processing. In this article the method of difference images and its adaptation for automatic applications is also analysed. In particular, a complementary pair of images is proposed as the main presentation of a difference image which allows automatic separation of the changes of ground objects without loss or distortion. The use of the histograms obtained by variations of image brightness (increasing and decreasing) provides opportunities for the assessment and experimental verification of existing approaches in the selection of automatic detection thresholds. The assessment of the implementations of the algorithms of Kittler, Kapur, Otsu, and the method of mean risk minimum demonstrate the instability of their solutions, wide variance in of results, as well as inconsistencies with the visual approaches to the selection of the binarization thresholds. A new algorithm for the automatic detection and analysis of the brightness changes of land areas is proposed. As a result, the automation of detection of each brightness change of a given land area is achieved in all available spectral channels of satellite imagery.

关键词： Land area Difference image Space imagery Change detection

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An unified approach for convolution-based image filtering on reconfigurable systems

An unified approach for convolution-based image filtering on...

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Southern Conference on Programmable Logic

作者： Jones Y. Mori Camilo Sánchez-Ferreira Daniel M. Muñoz Carlos H. Llanos Pedro Berger Department of Mechanical Engineering University of Brasilia Brazil Department of Computer Science University of Brasilia Brazil

Currently the market and the academic community have required applications of image and video processing with several real-time constraints. In order to seek an alternative design that allows the rapid development of real time image processing systems this paper proposes an unified hardware architecture for some image filtering algorithms in space domain, such as windowing-based operations, which are implemented on FPGAs (Field Programmable Gate Arrays). For achieving this, six different filters have been implemented in a parallel approach, separating them in simple hardware structures, allowing the algorithms to explore their parallel capabilities by using a simple systolic architecture. In this system all implemented algorithms run in parallel allowing the user to select a defined output for depicting it in a display. Both image processing and synthesis results have demonstrated the feasibility of FPGAs for implementing the proposed filtering algorithms in a full parallel approach.

关键词： Pixel Convolution image processing Computer architecture Field programmable gate arrays Real time systems Hardware

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Fast algorithms and Architectures for 8-Point DST-II/DST-vii Approximations

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JOURNAL OF CIRCUITS systems AND COMPUTERS 2017年第3期26卷 1750045-1750045页

作者： Cintra, Renato J. Bayer, Fabio M. Madanayake, Arjuna Potluri, Uma S. Edirisuriya, Amila Univ Fed Pernambuco Signal Proc Grp Dept Stat Recife PE Brazil Inst Natl Sci Appl LIRIS Lyon France Univ Rennes 1 INRIA IRISA Equipe Cairn Rennes France Univ Fed Santa Maria Dept Stat Santa Maria RS Brazil Univ Fed Santa Maria LACESM Santa Maria RS Brazil Univ Akron ECE Akron OH 44325 USA

Multiplier-free fast algorithms are derived and analyzed for realizing the 8-point discrete sine transform of type II and type vii (DST-II and DST-vii) transforms with applications in image and video compression. A new fast algorithm is identified using numerical search methods for approximating DST-vii without employing multipliers. In addition, recently proposed fast algorithms for approximating the 8-point DCT-II are now extended to approximate DST-II. All proposed approximations for DST-II and DST-vii are compared with ideal transforms, and circuit complexity is measured using FPGA-based rapid prototypes on a 90nm Xilinx Virtex-4 device. The proposed architectures find applications in emerging video processing standards such as H.265/HEVC.

关键词： Approximate discrete transforms DCT DST fast algorithms FPGA low-complexity transform

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Exoplanet Imaging Data Challenge: benchmarking the various image processing methods for exoplanet detection 7

Exoplanet Imaging Data Challenge: benchmarking the various i...

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Conference on Adaptive Optics systems vii

作者： Cantalloube, F. Gomez-Gonzalez, C. Absil, O. Cantero, C. Bacher, R. Bonse, J. M. Bottom, M. Dahlqvist, C. H. Desgrange, C. Flasseur, O. Fuhrmann, T. Henning, Th Jensen-Clem, R. Kenworthy, M. Mawet, D. Mesa, D. Meshkat, T. Mouillet, D. Mueller, A. Nasedkin, E. Pairet, B. Pierard, S. Ruffio, J. B. Samland, M. Stone, J. Van Droogenbroeck, M. Max Planck Inst Astron Konigstuhl 17 D-69117 Heidelberg Germany Barcelona Supercomp Ctr Barcelona Spain Univ Liege Space Sci Technol & Astrophys Res STAR Inst Allee Six Aout 19c B-4000 Liege Belgium Univ Liege Montefiore Inst B-4000 Liege Belgium Univ Grenoble Alpes IPAG CNRS F-38000 Grenoble France Swiss Fed Inst Technol Inst Particle Phys & Astrophys Wolfgang Pauli Str 27 CH-8093 Zurich Switzerland CALTECH Jet Prop Lab Pasadena CA 91125 USA Ecole Normale Super Lyon Dept Phys F-69364 Lyon France Univ Lyon Univ Lyon1 ENS Lyon CNRSCtr Rech Astrophys LyonUMR 5574 F-69230 St Genis Laval France Ostbayer TH Regensburg Germany Univ Calif Santa Cruz Astron Dept 1156 High St Santa Cruz CA 95064 USA Leiden Univ Leiden Observ POB 9513 NL-2300 RA Leiden Netherlands CALTECH Dept Astron 1200 E Calif Blvd Pasadena CA 91125 USA INAF Osservatorio Astron Padova Vicolo Osservatorio 5 I-35122 Padua Italy UCLouvain ELEN ICTEAM ISPGrp B-1348 Louvain La Neuve Belgium Stockholm Univ Dept Astron Stockholm Sweden Univ Arizona Steward Observ 933 N Cherry Ave Tucson AZ 85721 USA

ISBN: (纸本)9781510636842

The Exoplanet Imaging Data Challenge is a community-wide effort meant to offer a platform for a fair and common comparison of image processing methods designed for exoplanet direct detection. For this purpose, it gathers on a dedicated repository (Zenodo), data from several high-contrast ground-based instruments worldwide in which we injected synthetic planetary signals. The data challenge is hosted on the CodaLab competition platform, where participants can upload their results. The specifications of the data challenge are published on our website https://***/. The first phase, launched on the 1st of September 2019 and closed on the 1st of October 2020, consisted in detecting point sources in two types of common data-set in the field of high-contrast imaging: data taken in pupil-tracking mode at one wavelength subchallenge 1, also referred to as ADI) and multispectral data taken in pupil-tracking mode (subchallenge 2, also referred to as ADI+mSDI). In this paper, we describe the approach, organisational lessons-learnt and current limitations of the data challenge, as well as preliminary results of the participants' submissions for this first phase. In the future, we plan to provide permanent access to the standard library of data sets and metrics, in order to guide the validation and support the publications of innovative image processing algorithms dedicated to high-contrast imaging of planetary systems.

关键词： Exoplanet detection High-contrast imaging Adaptive Optics Coronagraphy Post-processing techniques Data challenge

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Optics and Photonics for Information processing vii

Optics and Photonics for Information Processing VII

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7th Conference of Optics and Photonics for Information processing

ISBN: (纸本)9780819497055

The proceedings contain 31 papers. The topics discussed include: PAPR mitigation algorithms for OFDM WiMAX link;implementation of a photonic antenna in optical OFDM link;optical signal impairment study of cascaded filters in 40 Gbps DQPSK and 100 Gbps PM-DQPSK systems;digital holographic tomography using a light back propagation method and its application for refractive index measurement;designing the acousto-optical cell for optical spectrometer incorporated into the Guillermo Haro astrophysical observatory;fast hologram pattern generation by wave field translation;storage density estimation for the phase-encoding and shift multiplexing holographic optical correlator;on-chip optical matrix-vector multiplier;highway traffic segmentation using super-resolution and Gaussian mixture model;using orthogonal self-loop coded aperture in a pushbroom computational spectral imager;and robustness of double random phase encoding spread-space spread-spectrum image watermarking technique.

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