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Deep learning-based image enhancement methods face a fundamental trade-off between computational efficiency and representational capacity. For example, although a conventional three-dimensional Look-Up Table (3D LUT) can process a degraded…

Computer Vision and Pattern Recognition · Computer Science 2025-09-30 Liubing Hu , Chen Wu , Anrui Wang , Dianjie Lu , Guijuan Zhang , Zhuoran Zheng

Accurately estimating the point spread function (PSF) of an optical system requires solving free-space wave propagation, which entails evaluating a diffraction integral. This integral is traditionally computed numerically using Fast Fourier…

Image and Video Processing · Electrical Eng. & Systems 2026-05-22 Nicholas Ganino , Qi Guo

Nonuniform Fourier data are routinely collected in applications such as magnetic resonance imaging, synthetic aperture radar, and synthetic imaging in radio astronomy. To acquire a fast reconstruction that does not require an online inverse…

Numerical Analysis · Mathematics 2016-10-05 Anne Gelb , Guohui Song

We present a new gravitational lens modelling technique designed to model high-resolution interferometric observations with large numbers of visibilities without the need to pre-average the data in time or frequency. We demonstrate the…

Instrumentation and Methods for Astrophysics · Physics 2021-01-06 Devon Powell , Simona Vegetti , John P. McKean , Cristiana Spingola , Francesca Rizzo , Hannah R. Stacey

In this article, a new method is discussed for the calibration and monitoring of photomultiplier tubes (PMTs). This method is based on a Discrete Fourier Transform (DFT) and it is fast and general so that it can be used in cases where an…

Instrumentation and Detectors · Physics 2020-03-26 L. N. Kalousis , J. P. A. M. de André , E. Baussan , M. Dracos

Fast Fourier Transform (FFT) is an essential tool in scientific and engineering computation. The increasing demand for mixed-precision FFT has made it possible to utilize half-precision floating-point (FP16) arithmetic for faster speed and…

Distributed, Parallel, and Cluster Computing · Computer Science 2021-04-26 Binrui Li , Shenggan Cheng , James Lin

Transformer-based methods have achieved remarkable results in image super-resolution tasks because they can capture non-local dependencies in low-quality input images. However, this feature-intensive modeling approach is computationally…

Computer Vision and Pattern Recognition · Computer Science 2025-03-27 Wei Long , Xingyu Zhou , Leheng Zhang , Shuhang Gu

In radar systems, high resolution in the Doppler dimension is important for detecting slow-moving targets as it allows for more distinct separation between these targets and clutter, or stationary objects. However, achieving sufficient…

Computer Vision and Pattern Recognition · Computer Science 2025-05-26 Denisa Qosja , Kilian Barth , Simon Wagner

Extended source size effects have been detected in photometric monitoring of gravitational microlensing events. We study similar effects in the centroid motion of an extended source lensed by a point mass. We show that the centroid motion…

Astrophysics · Physics 2015-06-24 Shude Mao , Hans J. Witt

Image computation is a fundamental tool for performance assessment of astronomical instrumentation, usually implemented by Fourier transform techniques. We review the numerical implementation, evaluating a direct implementation of the…

Astrophysics · Physics 2008-11-26 M. Gai , R. Cancelliere

One of the main computational bottlenecks when working with kernel based learning is dealing with the large and typically dense kernel matrix. Techniques dealing with fast approximations of the matrix vector product for these kernel…

Machine Learning · Computer Science 2024-04-29 Theresa Wagner , Franziska Nestler , Martin Stoll

We present a fast algorithm for computing the diffracted field from arbitrary binary (sharp-edged) planar apertures and occulters in the scalar Fresnel approximation, for up to moderately high Fresnel numbers ($\lesssim 10^3$). It uses a…

Instrumentation and Methods for Astrophysics · Physics 2020-12-18 Alex H. Barnett

The nonlinear Fourier transform (NFT) has recently gained significant attention in fiber optic communications and other engineering fields. Although several numerical algorithms for computing the NFT have been published, the design of…

Signal Processing · Electrical Eng. & Systems 2019-10-17 Shrinivas Chimmalgi , Peter J. Prins , Sander Wahls

We present a method to compute the magnification of a finite source star lensed by a triple lens system based on the image boundary (contour integration) method. We describe a new procedure to obtain continuous image boundaries from…

Instrumentation and Methods for Astrophysics · Physics 2021-03-03 Renkun Kuang , Shude Mao , Tianshu Wang , Weicheng Zang , Richard J. Long

This paper details the purpose, difficulties, theory, implementation, and results of developing a Fast Fourier Transform (FFT) using the prime factor algorithm on an embedded system. Many applications analyze the frequency content of…

Hardware Architecture · Computer Science 2025-01-22 Josh Vernon , D. G. Perera

Non-line-of-Sight (NLOS) imaging systems collect light at a diffuse relay surface and input this measurement into computational algorithms that output a 3D volumetric reconstruction. These algorithms utilize the Fast Fourier Transform (FFT)…

Image and Video Processing · Electrical Eng. & Systems 2025-01-14 Talha Sultan , Alex Bocchieri , Chaoying Gu , Xiaochun Liu , Pavel Polynkin , Andreas Velten

Spectra derived from fast Fourier transform (FFT) analysis of time-domain data intrinsically contain statistical fluctuations whose distribution depends on the number of accumulated spectra contributing to a measurement. The tail of this…

Solar and Stellar Astrophysics · Physics 2015-06-19 Gelu M. Nita , Gregory D. Fleishman , Dale E. Gary , William Marin , Kristine Boone

Microlensing promises to be a powerful tool for studying distant galaxies and quasars. As the data and models improve, there are systematic effects that need to be explored. Quasar continuum and broad-line regions may respond differently to…

Astrophysics · Physics 2008-11-26 Arthur B. Congdon , Charles R. Keeton , S. J. Osmer

Improving model robustness in case of corrupted images is among the key challenges to enable robust vision systems on smart devices, such as robotic agents. Particularly, robust test-time performance is imperative for most of the…

Computer Vision and Pattern Recognition · Computer Science 2025-10-13 Elena Camuffo , Umberto Michieli , Jijoong Moon , Daehyun Kim , Mete Ozay

Fourier ptychographic microscopy (FPM) is a promising computational imaging technique with high resolution, wide field-of-view (FOV) and quantitative phase recovery. So far, a series of system errors that may corrupt the image quality of…

Image and Video Processing · Electrical Eng. & Systems 2023-03-29 An Pan , Aiye Wang , Junfu Zheng , Yuting Gao , Caiwen Ma , Baoli Yao