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Related papers: Peak-locking centroid bias in Shack-Hartmann wavef…

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In this paper we present a differential approach to photo-polarimetric shape estimation. We propose several alternative differential constraints based on polarisation and photometric shading information and show how to express them in a…

Computer Vision and Pattern Recognition · Computer Science 2017-08-28 Silvia Tozza , William A. P. Smith , Dizhong Zhu , Ravi Ramamoorthi , Edwin R. Hancock

In adaptive optics, the measurement of spatial coherence length helps in deciding the optimum design parameters of a Shack Hartmann Sensor (SHS). Two methods of estimating the spatial coherence length of optical wavefronts are presented.…

Instrumentation and Methods for Astrophysics · Physics 2009-11-08 Akondi Vyas , M. B. Roopashree , B. Raghavendra Prasad

Center-based clustering algorithms (e.g., K-means) are popular for clustering tasks, but they usually struggle to achieve high accuracy on complex datasets. We believe the main reason is that traditional center-based clustering algorithms…

Machine Learning · Computer Science 2025-03-26 Qi Li

In crowded fields, small-aperture photometry can reduce contamination errors from neighboring sources compared to larger aperture photometry. However, the UVIS encircled energy (EE) varies with detector position and focus variations on…

Instrumentation and Methods for Astrophysics · Physics 2025-10-28 K. Huynh , V. Bajaj , J. Mack , A. Calamida

Liquid Chromatography coupled to Mass Spectrometry (LC-MS) based methods are commonly used for high-throughput, quantitative measurements of the proteome (i.e. the set of all proteins in a sample at a given time). Targeted LC-MS produces…

Computer Vision and Pattern Recognition · Computer Science 2020-10-28 Leon L. Xu , Hannes L. Röst

Automated particle locating algorithms have revolutionized microscopy image analysis, enabling researchers to rapidly locate many particles to within a few pixels in a microscope image. The vast majority of these algorithms operate through…

Soft Condensed Matter · Physics 2018-03-13 Brian D. Leahy , Matthew Bierbaum , James Sethna , Itai Cohen

Existing methods for rotation estimation between two spherical ($\mathbb{S}^2$) patterns typically rely on spherical cross-correlation maximization between two spherical function. However, these approaches exhibit computational complexities…

Computer Vision and Pattern Recognition · Computer Science 2025-08-05 Anik Sarker , Alan T. Asbeck

The advancement in sensitivity and field of view of next-generation wide-field survey telescopes requires astrometric measurements with high precision, even in the presence of significant geometric distortions. To address this challenge, we…

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star. A major limitation for such direct imaging is the speckle noise that is induced from the…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 JiangPei Dou , DeQing Ren , YongTian Zhu , Xi Zhang

Center-based clustering is a fundamental primitive for data analysis and becomes very challenging for large datasets. In this paper, we focus on the popular $k$-median and $k$-means variants which, given a set $P$ of points from a metric…

Distributed, Parallel, and Cluster Computing · Computer Science 2019-10-01 Alessio Mazzetto , Andrea Pietracaprina , Geppino Pucci

Radars provide robust perception of vehicle surroundings by effectively functioning in poor light and adverse weather conditions. Synthetic aperture radar (SAR) algorithms are employed to address the limited angular resolution of radars by…

Signal Processing · Electrical Eng. & Systems 2026-03-10 S. Hamed Javadi , André Bourdoux , Adnan Albaba , Hichem Sahli

The paper presents the results from a multi-year effort to develop and validate image processing methods for selecting the best physical models based on solar image observations. The approach consists of selecting the physical models based…

Image and Video Processing · Electrical Eng. & Systems 2022-01-06 V. Jatla , M. S. Pattichis , C. N. Arge

We propose and examine the use of biphoton pairs, such as those created in parametric down conversion or four-wave mixing, to enhance the precision and the resolution of measuring optical displacements by position-sensitive detection. We…

Quantum Physics · Physics 2016-05-04 Kevin Lyons , Shengshi Pang , Paul G. Kwiat , Andrew N. Jordan

Autofocus is an important task for digital cameras, yet current approaches often exhibit poor performance. We propose a learning-based approach to this problem, and provide a realistic dataset of sufficient size for effective learning. Our…

Computer Vision and Pattern Recognition · Computer Science 2020-05-05 Charles Herrmann , Richard Strong Bowen , Neal Wadhwa , Rahul Garg , Qiurui He , Jonathan T. Barron , Ramin Zabih

This work addresses the challenge of sub-pixel accuracy in detecting 2D local features, a cornerstone problem in computer vision. Despite the advancements brought by neural network-based methods like SuperPoint and ALIKED, these modern…

Computer Vision and Pattern Recognition · Computer Science 2024-07-17 Shinjeong Kim , Marc Pollefeys , Daniel Barath

Extreme wavefront correction is required for coronagraphs on future space telescopes to reach 1e-8 or better starlight suppression for the direct imaging and characterization of exoplanets in reflected light. Thus, a suite of wavefront…

Spectral clustering is a celebrated algorithm that partitions objects based on pairwise similarity information. While this approach has been successfully applied to a variety of domains, it comes with limitations. The reason is that there…

Statistics Theory · Mathematics 2018-05-24 Kwangjun Ahn , Kangwook Lee , Changho Suh

A variety of on-orbit imaging and spectroscopic observations are used to characterize the Charge Transfer Efficiency (CTE) of the Charge-Coupled Device (CCD) of the Space Telescope Imaging Spectrograph (STIS) aboard the Hubble Space…

Astrophysics · Physics 2009-11-11 Paul Goudfrooij , Ralph C. Bohlin , Jesus Maiz-Apellaniz , Randy A. Kimble

In this work, we propose a method for computing centroids, or barycenters, in the spectral Wasserstein-2 metric for sets of power spectral densities, where the barycenters are restricted to belong to the set of all-pole spectra with a…

Signal Processing · Electrical Eng. & Systems 2026-02-17 Rumeshika Pallewela , Filip Elvander

We present an optical wavefront shaping approach that allows tracking and localization of signal hidden inside or behind a scattering medium. The method combines traditional feedback based wavefront shaping together with a switch function,…

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