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Recovering sharper images from blurred observations, referred to as deconvolution, is an ill-posed problem where classical approaches often produce unsatisfactory results. In ground-based astronomy, combining multiple exposures to achieve…

Computer Vision and Pattern Recognition · Computer Science 2025-10-07 Fausto Navarro , Daniel Hall , Tamas Budavari , Yashil Sukurdeep

We consider a stochastic gradient descent (SGD) algorithm for solving linear inverse problems (e.g., CT image reconstruction) in the Banach space framework of variable exponent Lebesgue spaces $\ell^{(p_n)}(\mathbb{R})$. Such non-standard…

Optimization and Control · Mathematics 2023-03-17 Marta Lazzaretti , Zeljko Kereta , Luca Calatroni , Claudio Estatico

A long-standing issue in solar ground-based observations has been the contamination of data due to stray light, which is particularly relevant in inversions of spectropolarimetric data. We aim to build on a statistical method of correcting…

Solar and Stellar Astrophysics · Physics 2021-12-07 Sudharshan Saranathan , Michiel van Noort , Sami K. Solanki

Astronomical imaging using aperture synthesis telescopes requires deconvolution of the point spread function as well as calibration of instrumental and atmospheric effects. In general, such effects are time-variable and vary across the…

Astrophysics · Physics 2009-11-13 S. Bhatnagar , T. J. Cornwell , K. Golap , Juan M. Uson

When a telescope doesn't reach a reasonable point spread function on the detector or detectable wavefront quality after initial assembly, a coarse phase alignment on-sky is crucial. Before utilizing a closed loop adaptive optics system, the…

Instrumentation and Methods for Astrophysics · Physics 2024-09-10 Solvay Blomquist , Heejoo Choi , Hyukmo Kang , Kevin Derby , Pierre Nicolas , Ewan S. Douglas , Daewook Kim

The spatial resolution of astronomical images is limited by atmospheric turbulence and diffraction in the telescope optics, resulting in blurred images. This makes it difficult to accurately measure the brightness of blended objects because…

Instrumentation and Methods for Astrophysics · Physics 2023-05-31 Kevin Michalewicz , Martin Millon , Frédéric Dux , Frédéric Courbin

An unbiased method for improving the resolution of astronomical images is presented. The strategy at the core of this method is to establish a linear transformation between the recorded image and an improved image at some desirable…

Astrophysics · Physics 2016-08-30 F. P. Pijpers

We seek to find a shapelet-based scheme for deconvolving galaxy images from the PSF which leads to unbiased shear measurements. Based on the analytic formulation of convolution in shapelet space, we construct a procedure to recover the…

Astrophysics · Physics 2015-03-03 Peter Melchior , Rene Andrae , Matteo Maturi , Matthias Bartelmann

In this paper, we provide an in-depth study of Stochastic Backpropagation (SBP) when training deep neural networks for standard image classification and object detection tasks. During backward propagation, SBP calculates the gradients by…

Computer Vision and Pattern Recognition · Computer Science 2022-10-04 Jun Fang , Mingze Xu , Hao Chen , Bing Shuai , Zhuowen Tu , Joseph Tighe

This paper demonstrates a practical method that can correct spatial varying blur from a set of images of the same object. The algorithm jointly estimates the object and local point spread functions~(PSF). The method prioritizes sections…

Image and Video Processing · Electrical Eng. & Systems 2020-11-04 Wouter van de Ketterij , Oleg Soloviev , Michel Verhaegen

Image subtraction is essential for transient detection in time-domain astronomy. The point spread function (PSF), photometric scaling, and sky background generally vary with time and across the field-of-view for imaging data taken with…

Instrumentation and Methods for Astrophysics · Physics 2022-09-14 Lei Hu , Lifan Wang , Xingzhuo Chen , Jiawen Yang

The study of astronomical phenomena through ground-based observations is always challenged by the distorting effects of Earth's atmosphere. Traditional methods of post-facto image correction, essential for correcting these distortions,…

Instrumentation and Methods for Astrophysics · Physics 2024-08-14 A. Asensio Ramos

We propose a new, two-stage algorithm for inverting strong gravitational lenses. The key to the algorithm is decoupling the effects of lens magnification and intrinsic structure in the background source in the appearance of lensed arcs.…

Astrophysics · Physics 2007-05-23 P. Newbury , G. G. Fahlman

Accurate and precise measurements of the Hubble constant are critical for testing our current standard cosmological model and revealing possibly new physics. With Hubble Space Telescope (HST) imaging, each strong gravitational lens system…

3D Gaussian Splatting (3DGS) has emerged as a promising approach for 3D scene representation, offering a reduction in computational overhead compared to Neural Radiance Fields (NeRF). However, 3DGS is susceptible to high-frequency artifacts…

Computer Vision and Pattern Recognition · Computer Science 2024-09-06 Shen Chen , Jiale Zhou , Lei Li

Spike cameras, as an innovative neuromorphic camera that captures scenes with the 0-1 bit stream at 40 kHz, are increasingly employed for the 3D reconstruction task via Neural Radiance Fields (NeRF) or 3D Gaussian Splatting (3DGS). Previous…

Computer Vision and Pattern Recognition · Computer Science 2025-06-26 Kang Chen , Jiyuan Zhang , Zecheng Hao , Yajing Zheng , Tiejun Huang , Zhaofei Yu

We present STARRED, a Point Spread Function (PSF) reconstruction, two-channel deconvolution, and light curve extraction method designed for high-precision photometric measurements in imaging time series. An improved resolution of the data…

Instrumentation and Methods for Astrophysics · Physics 2024-07-25 Martin Millon , Kevin Michalewicz , Frédéric Dux , Frédéric Courbin , Philip J. Marshall

Remarkable development of cosmology is benefited from the increasingly improved measurements of cosmic distances including absolute distances and relative distances. In recent years, however, the emerged cosmological tensions motivate us to…

Cosmology and Nongalactic Astrophysics · Physics 2022-04-21 Jing-Zhao Qi , Wei-Hong Hu , Yu Cui , Jing-Fei Zhang , Xin Zhang

We examined the solar gravitational lens (SGL) as the means to produce direct high-resolution, multipixel images of exoplanets. The properties of the SGL are remarkable: it offers maximum light amplification of ~1e11 and angular resolution…

Current trends in scientific imaging are challenged by the emerging need of integrating sophisticated machine learning with Big Data analytics platforms. This work proposes an in-memory distributed learning architecture for enabling…

Distributed, Parallel, and Cluster Computing · Computer Science 2018-10-01 A. Panousopoulou , S. Farrens , K. Fotiadou , A. Woiselle , G. Tsagkatakis , J-L. Starck , P. Tsakalides