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A Gaussian Scale Space Approach For Exudates Detection, Classification And Severity Prediction [article]

Mrinal Haloi, Samarendra Dandapat, Rohit Sinha
2015 arXiv   pre-print
For exudate detection the proposed method achieved a sensitivity of 96.54% and prediction of 98.35% in DIARETDB1V2 database.  ...  In the context of Computer Aided Diagnosis system for diabetic retinopathy, we present a novel method for detection of exudates and their classification for disease severity prediction.  ...  Also we want to ensure that artifacts like flares gets removed from GIMAP. From observation it has been noticed that flares are circular shape object.  ... 
arXiv:1505.00737v1 fatcat:dd2ua26mw5eolgkadazfxsxriu

Spots And Flares: Stellar Activity In The Time Domain Era

James Davenport, Suzanne Hawley, Leslie Hebb, Zeljko Ivezic
2015 Zenodo  
Flares can be detected in sparsely sampled wide field surveys by searching for bright single-point outliers in light curves.  ...  The goal of this thesis is to develop techniques for detecting and analyzing the most prominent forms of magnetic activity from low-mass stars in modern time domain surveys: starspots and flares.  ...  Automatic Selection The first step in our flare selection from the short cadence light curve was an unsupervised detection of candidate flare events.  ... 
doi:10.5281/zenodo.47231 fatcat:x5wjw45zd5fhzkblog7bnzuzrq

A Multi-wavelength Analysis of Active Regions and Sunspots by Comparison of Automatic Detection Algorithms

C. Verbeeck, P. A. Higgins, T. Colak, F. T. Watson, V. Delouille, B. Mampaey, R. Qahwaji
2011 Solar Physics  
Citation: Verbeeck C, Higgins PA, Colak T, Watson FT, Delouille V, Mampaey B and Qahwaji RSR (2013) A multi-wavelength analysis of active regions and sunspots by comparison of automatic detection algortihms  ...  This article details four algorithms developed separately at the Universities of Bradford and Glasgow, the Royal Observatory of Belgium and Trinity College Dublin for the purposes of automated detection  ...  Ahmed for allowing us the use of the Ising Energy software he was involved in developing.  ... 
doi:10.1007/s11207-011-9859-6 fatcat:mbfwqyld2bgwlf62jbfb4lmcxa

Let's See Clearly: Contaminant Artifact Removal for Moving Cameras [article]

Xiaoyu Li, Bo Zhang, Jing Liao, Pedro V. Sander
2021 arXiv   pre-print
In this paper, we propose a video restoration method to automatically remove these contaminants and produce a clean video.  ...  Our approach first seeks to detect attention maps that indicate the regions that need to be restored.  ...  To this end, we first train the network to automatically spot the contaminant artifacts which are usually prominent in the flow maps of a video with a moving camera.  ... 
arXiv:2104.08852v1 fatcat:lrourka56zehblzb7ng34li73q

Glare aware photography

Ramesh Raskar, Amit Agrawal, Cyrus A. Wilson, Ashok Veeraraghavan
2008 ACM SIGGRAPH 2008 papers on - SIGGRAPH '08  
By statistically analyzing the ray-space inside a camera, we can classify and remove glare artifacts. In ray-space, glare behaves as high frequency noise and can be reduced by outlier rejection.  ...  Our approach handles photography looking into the sun and photos taken without a hood, removes the effect of lens smudges and reduces loss of contrast due to camera body reflections.  ...  We thank Clifton Forlines and Takafumi Aoki for help in preparing the video.  ... 
doi:10.1145/1399504.1360655 fatcat:dbyrcxwifveazksidtpoe7kqse

Glare aware photography

Ramesh Raskar, Amit Agrawal, Cyrus A. Wilson, Ashok Veeraraghavan
2008 ACM Transactions on Graphics  
By statistically analyzing the ray-space inside a camera, we can classify and remove glare artifacts. In ray-space, glare behaves as high frequency noise and can be reduced by outlier rejection.  ...  Our approach handles photography looking into the sun and photos taken without a hood, removes the effect of lens smudges and reduces loss of contrast due to camera body reflections.  ...  We thank Clifton Forlines and Takafumi Aoki for help in preparing the video.  ... 
doi:10.1145/1360612.1360655 fatcat:5e4yj3b6z5hq5nr634owithnzu

Mosaicking and Demosaicking in the Design of Multispectral Digital Cameras [chapter]

2018 Single-Sensor Imaging  
Automatic red-eye detection and removal is needed to eliminate red-eye effects in digital or digitized film photographs.  ...  Face detection can also help to improve performance of automatic red-eye removal and to produce visually pleasing photographs with enhanced color and tonal quality by setting the optimal white balance  ... 
doi:10.1201/9781315219363-13 fatcat:ep2vioqh6rgabaw7znc5n7rs2m

RGB cameras failures and their effects in autonomous driving applications [article]

Francesco Secci, Andrea Ceccarelli
2022 arXiv   pre-print
To support the definition of safe and robust vehicle architectures and intelligent systems, in this paper we define the failure modes of a vehicle camera, together with an analysis of effects and known  ...  The resulting misbehaviors with respect to operating with clean images allow a better understanding of failures effects and the related safety risks in image-based applications.  ...  ACKNOWLEDGMENT This work has been partially supported by the H2020 programme under the Marie Sklodowska-Curie grant agreement 823788 (ADVANCE) project and by the project POR-CREO SPACE "Smart PAssenger  ... 
arXiv:2008.05938v3 fatcat:f2glidprlvdpnbjxq6crxcv36u

Polishing PMMA and other optical polymers with magnetorheological finishing

Jessica E. DeGroote, Henry J. Romanofsky, Irina A. Kozhinova, John M. Schoen, Stephen D. Jacobs, H. Philip Stahl
2004 Optical Manufacturing and Testing V  
maps and removal spot data.  ...  (All photographs are to the scale indicated in the figure.)  ...  Of the other abrasive/polymer combinations tested, Al 2 O 3 showed the greatest potential for processing COP, PS, and PC without roughening or introducing surface artifacts.  ... 
doi:10.1117/12.506860 fatcat:fmtbwt67kzdrdeez4apeitmcni

Qualitative and Quantitative Assessment of Metal Artifacts Arising from Implantable Cardiac Pacing Devices in Oncological PET/CT Studies: A Phantom Study

Mohammad R. Ay, Abolfazl Mehranian, Mehrsima Abdoli, Pardis Ghafarian, Habib Zaidi
2011 Molecular Imaging and Biology  
We also assess the efficacy of a metal artifact reduction (MAR) algorithm along with the severity of artifacts in the presence of misalignment between μ-maps and PET images.  ...  to bright and dark streak artifacts, respectively.  ...  areas, thus producing hot spots and as such the effect of metal artifacts becomes more severe.  ... 
doi:10.1007/s11307-010-0467-x pmid:21203854 fatcat:6nayetllrrdvff6sewhdzo72dy

RGB cameras failures and their effects in autonomous driving applications

Andrea Ceccarelli, Francesco Secci
2022 IEEE Transactions on Dependable and Secure Computing  
To support the definition of safe and robust vehicle architectures and intelligent systems, in this paper we define the failure modes of a vehicle camera, together with an analysis of effects and known  ...  The resulting misbehaviors with respect to operating with clean images allow a better understanding of failures effects and the related safety risks in image-based applications.  ...  For more information, see https://creativecommons.org/licenses/by/4.0/ This article has been accepted for publication in a future issue of this journal, but has not been fully edited.  ... 
doi:10.1109/tdsc.2022.3156941 fatcat:lo5fgfxvhrgwdha4fywtygk7cu

The New 2018 Version of the Meudon Spectroheliograph

J.-M. Malherbe, K. Dalmasse
2019 Solar Physics  
Daily full-disk observations of the solar photosphere and chromosphere started at Meudon Observatory in 1908.  ...  After a review of the scientific context and the historical background, we describe the instrumental characteristics and capabilities of the new version operating since 2018.  ...  Ribes who directed Meudon solar observations during many years and passed away prematurely in 1996. We thank the referee for helpful comments and suggestions.  ... 
doi:10.1007/s11207-019-1441-7 fatcat:cisjiv35aveqzfeog6zcytgbae

The Vanishing Appearing Sources during a Century of Observations project: I. USNO objects missing in modern sky surveys and follow-up observations of a "missing star" [article]

Beatriz Villarroel, Johan Soodla, Sébastien Comerón, Lars Mattsson, Kristiaan Pelckmans, Martín López-Corredoira, Kevin Krisciunas, Eduardo Guerras, Oleg Kochukhov, Josefine Bergstedt, Bart Buelens, Rudolf E. Bär, Rubén Cubo (+8 others)
2019 arXiv   pre-print
We find about ∼ 100 point sources visible in only one epoch in the red band of the USNO which may be of interest in searches for strong M dwarf flares, high-redshift supernovae or other catagories of unidentified  ...  We show that these objects are redder and have larger proper motions than typical USNO objects.  ...  Salman Toor assisted in operating the resources. B.V. wishes to thank Geoffrey Marcy for many great ideas, discussions and suggestions that improved the project and the manuscript.  ... 
arXiv:1911.05068v2 fatcat:3bdhves2qfh6jf3tbuiulmjdpa

Digital Restoration by Denoising and Binarization of Historical Manuscripts Images [chapter]

Dimitrios Ventzas, Nikolaos Ntogas, Maria-Malamo Ventz
2012 Advanced Image Acquisition, Processing Techniques and Applications I  
Bernsen's method produced best results in manuscripts with characters with "spots and stains" and "red coloured characters".  ...  Other filters reproduce the effect of aging in old, traditional black-and-white photographs, toned with shades of brown, seefig. 15.  ...  An important feature of the book is its emphasis on software tools and scientific computing in order to enhance results and arrive at problem solution.  ... 
doi:10.5772/36734 fatcat:vltldnpgingxfoy256wzwq5ee4

The RHESSI Spectrometer [chapter]

D. M. Smith, R. P. Lin, P. Turin, D. W. Curtis, J. H. Primbsch, R. D. Campbell, R. Abiad, P. Schroeder, C. P. Cork, E. L. Hull, D. A. Landis, N. W. Madden (+8 others)
2003 The Reuven Ramaty High-Energy Solar Spectroscopic Imager (RHESSI)  
Detector segmentation, fast signal processing, and two sets of movable attenuators allow RHESSI to make high-quality spectra and images of flares across seven orders of magnitude in intensity.  ...  Here we describe the configuration and operation of the RHESSI spectrometer, show early results on in-flight performance, and discuss the principles of spectroscopic data analysis used by the RHESSI software  ...  We would like to recognize our colleagues at the Space Sciences Laboratory who participated in calibration and testing of the spectrometer: engineers Peter Harvey (also the RHESSI Project Manager) and  ... 
doi:10.1007/978-94-017-3452-3_2 fatcat:pk26wkcerbcofpkcmws44ryyli
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