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Related papers: Point Spread Function Estimation of Defocus

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The resolution of optical imaging is classically limited by the width of the point-spread function, which in turn is determined by the Rayleigh length. Recently, spatial-mode demultiplexing (SPADE) has been proposed as a method to achieve…

Quantum Physics · Physics 2025-02-26 Giuseppe Buonaiuto , Cosmo Lupo

In the imaging process of an astronomical telescope, the deconvolution of its beam or Point Spread Function (PSF) is a crucial task. However, deconvolution presents a classical and challenging inverse computation problem. In scenarios where…

Instrumentation and Methods for Astrophysics · Physics 2024-03-05 Shulei Ni , Yisheng Qiu , Yunchun Chen , Zihao Song , Hao Chen , Xuejian Jiang , Huaxi Chen

We proposed a deconvolution optical-resolution photoacoustic microscope for high -resolution imaging of brain. The focal spot of the photoacoustic microscopy is measured to obtain the lateral PSF (point spread function) of the system.…

Medical Physics · Physics 2020-11-05 Xianlin Song , Lingfang Song , Anqing Chen , Jianshuang Wei

Mesh deformation plays a pivotal role in many 3D vision tasks including dynamic simulations, rendering, and reconstruction. However, defining an efficient discrepancy between predicted and target meshes remains an open problem. A prevalent…

Computer Vision and Pattern Recognition · Computer Science 2024-03-19 Tung Le , Khai Nguyen , Shanlin Sun , Kun Han , Nhat Ho , Xiaohui Xie

Our aim is to estimate the perspective-effected geometric distortion of a scene from a video feed. In contrast to all previous work we wish to achieve this using from low-level, spatio-temporally local motion features used in commercial…

Computer Vision and Pattern Recognition · Computer Science 2015-04-22 Ognjen Arandjelovic , Duc-Son Pham , Svetha Venkatesh

Computational photography encompasses a diversity of imaging techniques, but one of the core operations performed by many of them is to compute image differences. An intuitive approach to computing such differences is to capture several…

Computer Vision and Pattern Recognition · Computer Science 2017-05-22 Clara Callenberg , Felix Heide , Gordon Wetzstein , Matthias Hullin

Adaptive optics (AO) system performance is improved using post-processing techniques, such as point spread function (PSF) deconvolution. The PSF estimation involves characterization of the different wavefront (WF) error sources in the AO…

Instrumentation and Methods for Astrophysics · Physics 2018-08-29 Florian Ferreira , Eric Gendron , Gérard Rousset , Damien Gratadour

This paper introduces a novel approach to the fine alignment of images in a burst captured by a handheld camera. In contrast to traditional techniques that estimate two-dimensional transformations between frame pairs or rely on discrete…

Computer Vision and Pattern Recognition · Computer Science 2023-12-11 Bruno Lecouat , Yann Dubois de Mont-Marin , Théo Bodrito , Julien Mairal , Jean Ponce

Astigmatic Defocus Sensor is a very simple and easy technique for measuring the amount of defocus (deviation from the focal plane) present in an optical beam. The approach uses a cylindrical lens to focus the beam and the measure of the…

Optics · Physics 2023-01-24 Santau Konwar

Diffusion models are extensively used for modeling image priors for inverse problems. We introduce \emph{Diff-Unfolding}, a principled framework for learning posterior score functions of \emph{conditional diffusion models} by explicitly…

Image and Video Processing · Electrical Eng. & Systems 2025-05-22 Yuanhao Wang , Shirin Shoushtari , Ulugbek S. Kamilov

The use of Wavefront Sensors (WFS) is nowadays fundamental in the field of instrumental optics. This paper discusses the principle of an original and recently proposed new class of WFS. Their principle consists in evaluating the slopes of…

Optics · Physics 2011-05-23 Francois Henault

Depth estimation from 2D images is a common computer vision task that has applications in many fields including autonomous vehicles, scene understanding and robotics. The accuracy of a supervised depth estimation method mainly relies on the…

Computer Vision and Pattern Recognition · Computer Science 2024-04-12 Muhammad Adeel Hafeez , Michael G. Madden , Ganesh Sistu , Ihsan Ullah

Monocular depth estimation is still an open challenge due to the ill-posed nature of the problem at hand. Deep learning based techniques have been extensively studied and proved capable of producing acceptable depth estimation accuracy even…

Image and Video Processing · Electrical Eng. & Systems 2022-04-15 Mazen Mel , Muhammad Siddiqui , Pietro Zanuttigh

We introduce a new algorithm for interpolating measurements of the point-spread function (PSF) using stars from many exposures. The principal components of the variation in the PSF pattern from multiple exposures are used to solve for…

Astrophysics · Physics 2007-05-23 Mike Jarvis , Bhuvnesh Jain

We employ electrostatic conversion drift calculations to match CCD pixel signal covariances observed in flat field exposures acquired using candidate sensor devices for the LSST Camera. We thus constrain pixel geometry distortions present…

Deconvolution of the telescope Point Spread Function (PSF) is necessary for even moderate dynamic range imaging with interferometric telescopes. The process of deconvolution can be treated as a search for a model image such that the…

Astrophysics · Physics 2009-11-10 S. Bhatnagar , T. J. Cornwell

Modern optical flow methods make use of salient scene feature points detected and matched within the scene as a basis for sparse-to-dense optical flow estimation. Current feature detectors however either give sparse, non uniform point…

Computer Vision and Pattern Recognition · Computer Science 2019-05-21 Felix Stephenson , Toby Breckon , Ioannis Katramados

We present an algorithm to derive difference images for data taken with the JWST with matched point-spread functions (PSFs). It is based on the saccadic fast Fourier transform (SFFT) method but with revisions to accommodate the rotations…

Instrumentation and Methods for Astrophysics · Physics 2024-04-30 Lei Hu , Lifan Wang

We have shown that the vector of the point spread function (PSF) lexicographical presentation belongs to the left side conjugated null space (NS) of the autoregression (AR) matrix operator on condition the AR parameters are common for…

Computer Vision and Pattern Recognition · Computer Science 2015-03-02 Yuriy A. Bunyak , Roman N. Kvetnyy , Olga Yu. Sofina

Previous studies determining which astronomical photometry software is best suited for a particular dataset are usually focused on speed, source classification, and/or meeting a sensitivity requirement. For faint objects in particular, the…

Instrumentation and Methods for Astrophysics · Physics 2013-05-27 Sarah Sonnett , Karen Meech , Robert Jedicke , Schelte Bus , John Tonry , Olivier Hainaut
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