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Thermal images from low-cost cameras often suffer from low resolution, fixed pattern noise, and other localized degradations. Available datasets for thermal imaging are also limited in both size and diversity. To address these challenges,…

Computer Vision and Pattern Recognition · Computer Science 2025-10-09 Piyush Dashpute , Niki Nezakati , Wolfgang Heidrich , Vishwanath Saragadam

High dynamic range (HDR) imaging is an important task in image processing that aims to generate well-exposed images in scenes with varying illumination. Although existing multi-exposure fusion methods have achieved impressive results,…

Computer Vision and Pattern Recognition · Computer Science 2023-05-30 Jun Xiao , Qian Ye , Tianshan Liu , Cong Zhang , Kin-Man Lam

Astrometric precision and knowledge of the point spread function are key ingredients for a wide range of astrophysical studies including time-delay cosmography in which strongly lensed quasar systems are used to determine the Hubble…

Instrumentation and Methods for Astrophysics · Physics 2021-09-22 Geoff C. -F. Chen , Tommaso Treu , Christopher D. Fassnacht , Sam Ragland , Thomas Schmidt , Sherry H. Suyu

Diffusing-wave spectroscopy is a powerful technique which consists in measuring the temporal correlation function of the intensity of light multiply scattered by a medium. In this paper, we apply this technique to cold atoms under purely…

We describe a scalable distributed imaging algorithm framework for next-generation radio telescopes, managing the Fourier transform from apertures to sky (or vice versa) with a focus on minimising memory load, data transfers, and…

Instrumentation and Methods for Astrophysics · Physics 2024-07-17 Peter Wortmann , James Kent , Bojan Nikolic

We present an algorithm capable of detecting diffuse, dim sources of any size in an astronomical image. These sources often defeat traditional methods for source finding, which expand regions around points of high intensity. Extended…

Instrumentation and Methods for Astrophysics · Physics 2016-01-05 T. Butler-Yeoman , M. Frean , C. P. Hollitt , D. W. Hogg , M. Johnston-Hollitt

Optical phase-spaces represent fields of any spatial coherence, and are typically measured through phase-retrieval methods involving a computational inversion, interference, or a resolution-limiting lenslet array. Recently, a weak-values…

Optics · Physics 2018-09-12 Samuel H. Knarr , Daniel J. Lum , James Schneeloch , John C. Howell

Differential Dynamic Microscopy (DDM) analyzes traditional real-space microscope images to extract information on sample dynamics in a way akin to light scattering, by decomposing each image in a sequence into Fourier modes, and evaluating…

Soft Condensed Matter · Physics 2017-11-10 Fabio Giavazzi , Paolo Edera , Peter J. Lu , Roberto Cerbino

The ill-posed problem of phase retrieval in optics, using one or more intensity measurements, has a multitude of applications using electromagnetic or matter waves. Many phase retrieval algorithms are computed on pixel arrays using discrete…

Image and Video Processing · Electrical Eng. & Systems 2022-09-21 J. A. Pollock , K. S. Morgan , L. C. P. Croton , M. K. Croughan , G. Ruben , N. Yagi , H. Sekiguchi , M. J. Kitchen

Fully sparse 3D detection has attracted an increasing interest in the recent years. However, the sparsity of the features in these frameworks challenges the generation of proposals because of the limited diffusion process. In addition, the…

Computer Vision and Pattern Recognition · Computer Science 2024-09-12 Tianran Liu , Morteza Mousa Pasandi , Robert Laganiere

We introduce Functional Diffusion Processes (FDPs), which generalize score-based diffusion models to infinite-dimensional function spaces. FDPs require a new mathematical framework to describe the forward and backward dynamics, and several…

Machine Learning · Computer Science 2023-12-19 Giulio Franzese , Giulio Corallo , Simone Rossi , Markus Heinonen , Maurizio Filippone , Pietro Michiardi

Pre-trained diffusion models have demonstrated remarkable proficiency in synthesizing images across a wide range of scenarios with customizable prompts, indicating their effective capacity to capture universal features. Motivated by this,…

Computer Vision and Pattern Recognition · Computer Science 2024-11-22 Yuxiang Ji , Boyong He , Chenyuan Qu , Zhuoyue Tan , Chuan Qin , Liaoni Wu

Volumetric optical microscopy using non-diffracting beams enables rapid imaging of 3D volumes by projecting them axially to 2D images but lacks crucial depth information. Addressing this, we introduce MicroDiffusion, a pioneering tool…

Image and Video Processing · Electrical Eng. & Systems 2024-03-19 Mude Hui , Zihao Wei , Hongru Zhu , Fei Xia , Yuyin Zhou

An approximation is elaborated for the paraxial propagation of diffracted beams, with both one- and two-dimensional cross sections, which are released from apertures with sharp boundaries. The approximation applies to any beam under the…

Optics · Physics 2016-06-29 Eitam Luz , Er'el Granot , Boris A. Malomed

In absence of a lens to form an image, incoherent or partially coherent light scattering off an obstructive or reflective object forms a broad intensity distribution in the far field with only feeble spatial features. We show here that…

We investigate the approximation efficiency of score functions by deep neural networks in diffusion-based generative modeling. While existing approximation theories utilize the smoothness of score functions, they suffer from the curse of…

Machine Learning · Computer Science 2023-09-21 Song Mei , Yuchen Wu

Over the past several decades, advances in telescope/detector technologies and deep imaging techniques have pushed surface brightness limits to ever fainter levels. We can now both detect and measure the diffuse, extended star light that…

Astrophysics of Galaxies · Physics 2019-09-23 J. Christopher Mihos

Metal-dielectric layered stacks for imaging with sub-wavelength resolution are regarded as linear isoplanatic systems - a concept popular in Fourier Optics and in scalar diffraction theory. In this context, a layered flat lens is a…

Optics · Physics 2010-09-21 Rafal Kotynski

This paper proposes a non-computational method of counteracting the effect of image degradation introduced by the diffraction phenomenon in lensless microscopy. All the optical images (whether focused by lenses or not) are diffraction…

Optics · Physics 2021-04-08 Sanjeev Kumar , Manjunatha Mahadevappa , Pranab Kumar Dutta

We present a general framework for matching the point-spread function (PSF), photometric scaling, and sky background between two images, a subject which is commonly referred to as difference image analysis (DIA). We introduce the new…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 D. M. Bramich , Keith Horne , M. D. Albrow , Y. Tsapras , C. Snodgrass , R. A. Street , M. Hundertmark , Noe Kains , A. Arellano Ferro , R. Figuera Jaimes , Sunetra Giridhar