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We propose a novel measure for template matching named Deformable Diversity Similarity -- based on the diversity of feature matches between a target image window and the template. We rely on both local appearance and geometric information…

Computer Vision and Pattern Recognition · Computer Science 2017-04-19 Itamar Talmi , Roey Mechrez , Lihi Zelnik-Manor

Laser-induced electron diffraction is an evolving tabletop method, which aims to image ultrafast structural changes in gas-phase polyatomic molecules with sub-{\AA}ngstr\"om spatial and femtosecond temporal resolution. Here, we provide the…

In this paper, we investigate a non-iterative imaging algorithm based on the topological derivative in order to retrieve the shape of penetrable electromagnetic inclusions when their dielectric permittivity and/or magnetic permeability…

Mathematical Physics · Physics 2013-05-14 Won-Kwang Park

In astronomy or biological imaging, refractive index inhomogeneities of e.g. atmosphere or tissues induce optical aberrations which degrade the desired information hidden behind the medium. A standard approach consists in measuring these…

Optics · Physics 2023-06-01 Tengfei Wu , Marc Guillon , Gilles Tessier , Pascal Berto

Transforming the instrumental photometry of ground-based telescopes into a calibrated physical flux in a well-defined passband is a major challenge in astronomy. Along with the intrinsic instrumental difference between telescopes sharing…

Instrumentation and Methods for Astrophysics · Physics 2025-07-08 S. Garrappa , E. O. Ofek , S. Ben-Ami , D. Polishook , A. Gal-Yam , Y. Shvartzvald , A. Krassilchtchikov , R. Konno , E. Segre , Y. M. Shani , Y. Sofer-Rimalt , M. Engel , A. Blumenzweig

LiDAR-based 3D panoptic segmentation often struggles with the inherent sparsity of data from LiDAR sensors, which makes it challenging to accurately recognize distant or small objects. Recently, a few studies have sought to overcome this…

Computer Vision and Pattern Recognition · Computer Science 2025-06-11 Yining Pan , Qiongjie Cui , Xulei Yang , Na Zhao

Active optics is defined as the control of the shape and the alignment of the components of an optical system at low temporal frequencies. For modern large telescopes with flexible monolithic or segmented primary mirrors and also flexible…

Astrophysics · Physics 2007-05-23 Lothar Noethe

Modern extreme adaptive optics (AO) systems achieving diffraction-limited performance open up new possibilities for instrumentation. Especially important for the fields of spectroscopy and interferometry is that it enables the prospect to…

Microscope objectives achieve near diffraction-limited performance only when used under the conditions they are designed for. In non-standard geometries, such as thick cover slips or curved surfaces, severe aberrations arise, inevitably…

Optics · Physics 2025-03-24 D. W. S. Cox , T. Knop , I. M. Vellekoop

The performance of a wide-field adaptive optics system depends on input design parameters. Here we investigate the performance of a multi-object adaptive optics system design for the European Extremely Large Telescope, using an end-to-end…

Instrumentation and Methods for Astrophysics · Physics 2016-09-21 Alastair Basden , Tim Morris

This paper introduces a novel variability report generator developed for the Large Array Survey Telescope (LAST), a cost-effective multi-purpose telescope array conducting a wide survey of the variable sky in the visible-light spectrum.…

Instrumentation and Methods for Astrophysics · Physics 2023-09-06 Barkotel Zemenu

We present an efficient algorithm for the least squares parameter fitting optimized for component separation in multi-frequency CMB experiments. We sidestep some of the problems associated with non-linear optimization by taking advantage of…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-26 Rishi Khatri

Depth map estimation from images is an important task in robotic systems. Existing methods can be categorized into two groups including multi-view stereo and monocular depth estimation. The former requires cameras to have large overlapping…

Computer Vision and Pattern Recognition · Computer Science 2022-10-06 Jialei Xu , Xianming Liu , Yuanchao Bai , Junjun Jiang , Kaixuan Wang , Xiaozhi Chen , Xiangyang Ji

We present the first on-sky results of the micro-lens ring tip-tilt (MLR-TT) sensor. This sensor utilizes a 3D printed micro-lens ring feeding six multi-mode fibers to sense misaligned light, allowing centroid reconstruction. A tip-tilt…

Wide-angle cameras are uniquely positioned for mobile robots, by virtue of the rich information they provide in a small, light, and cost-effective form factor. An accurate calibration of the intrinsics and extrinsics is a critical…

Computer Vision and Pattern Recognition · Computer Science 2022-10-07 Bardienus P Duisterhof , Yaoyu Hu , Si Heng Teng , Michael Kaess , Sebastian Scherer

METIS is a mid-infrared instrument proposed for the European Extremely Large Telescope (E-ELT). It is designed to provide imaging and spectroscopic capabilities in the 3 - 14 micron region up to a spectral resolution of 100000. One of the…

We present a new interferometric imaging approach that allows for multiple-depth imaging in a single acquisition, using off-axis low-coherence holographic multiplexing. This technique enables sectioned imaging of multiple slices within a…

Optics · Physics 2019-03-29 Lauren Wolbromsky , Nir A. Turko , Natan T. Shaked

Myopia is a manifestation of visual impairment caused by an excessively elongated eyeball. Image data is critical material for studying high myopia and pathological myopia. Measurements of spherical equivalent and axial length are the gold…

Computer Vision and Pattern Recognition · Computer Science 2023-12-13 Xiao Ma , Zetian Zhang , Zexuan Ji , Kun Huang , Na Su , Songtao Yuan , Qiang Chen

A geometric representation for multivariate extremes, based on the shapes of scaled sample clouds in light-tailed margins and their so-called limit sets, has recently been shown to connect several existing extremal dependence concepts.…

Methodology · Statistics 2023-11-03 Jennifer Wadsworth , Ryan Campbell

Estimating the homography between two images is crucial for mid- or high-level vision tasks, such as image stitching and fusion. However, using supervised learning methods is often challenging or costly due to the difficulty of collecting…

Computer Vision and Pattern Recognition · Computer Science 2024-11-21 Sanghyeob Song , Jaihyun Lew , Hyemi Jang , Sungroh Yoon