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Fourier analysis and representation of circular distributions in terms of their Fourier coefficients, is quite commonly discussed and used for model-free inference such as testing uniformity and symmetry etc. in dealing with 2-dimensional…

Methodology · Statistics 2018-02-27 S. Rao Jammalamadaka , Gyorgy Terdik

The current digital era, driven by growing threats to data security, requires a robust image encryption technique. Classical encryption algorithms suffer from a trade-off among security, image fidelity, and computational efficiency. This…

We present an efficient method for evaluating random phase errors in phase shifters within photonic integrated circuits, avoiding the computational cost of traditional Monte Carlo simulations. By modeling spatially correlated manufacturing…

Optics · Physics 2025-04-09 Zijian Zhang

The problem of computing the Fourier Transform of a signal whose spectrum is dominated by a small number $k$ of frequencies quickly and using a small number of samples of the signal in time domain (the Sparse FFT problem) has received…

Data Structures and Algorithms · Computer Science 2017-08-18 Michael Kapralov

Interferometers (e.g. ALMA and NOEMA) allow us to obtain the detailed brightness distribution of astronomical sources in 3 dimensions (R.A., Dec., frequency). However, the spatial correlation of the noise makes it difficult to evaluate the…

Instrumentation and Methods for Astrophysics · Physics 2023-02-21 Takafumi Tsukui , Satoru Iguchi , Ikki Mitsuhashi , Kenichi Tadaki

We discuss efficient algorithms for the accurate forward and reverse evaluation of the discrete Fourier-Bessel transform (dFBT) as numerical tools to assist in the 2D polar convolution of two radially symmetric functions, relevant, e.g., to…

Computational Physics · Physics 2016-11-08 O. Melchert , M. Wollweber , B. Roth

We present a proposal of a set-up to measure the work distribution due to an arbitrary unitary process acting on the spatial transverse degrees of freedom of a light beam. Hermite-Gaussian optical modes representing a quantum harmonic…

The distance transform (DT) and its many variations are ubiquitous tools for image processing and analysis. In many imaging scenarios, the images of interest are corrupted by noise. This has a strong negative impact on the accuracy of the…

Computer Vision and Pattern Recognition · Computer Science 2020-09-14 Johan Öfverstedt , Joakim Lindblad , Nataša Sladoje

One of the most efficient ways to produce unconditional simulations is with the kernel convolution using fast Fourier transform (FFT) [1]. However, when data is located on a surface, this approach is not efficient because data needs to be…

Computation · Statistics 2016-01-18 Alexander Gribov

Pseudospectral numerical schemes for solving the Dirac equation in general static curved space are derived using a pseudodifferential representation of the Dirac equation along with a simple Fourier-basis technique. Owing to the presence of…

Numerical Analysis · Mathematics 2020-04-22 Xavier Antoine , François Fillion-Gourdeau , Emmanuel Lorin , Steve McLean

We propose a data-driven Fourier-trained neural-network method for estimating fixed-horizon probability densities from empirical characteristic-function (CF) information. The estimator is a positive Gaussian--Laplace mixture with…

Machine Learning · Statistics 2026-05-19 Duy-Minh Dang , Volter Entoma

Estimating uncertainty of camera parameters computed in Structure from Motion (SfM) is an important tool for evaluating the quality of the reconstruction and guiding the reconstruction process. Yet, the quality of the estimated parameters…

Computer Vision and Pattern Recognition · Computer Science 2018-08-08 Michal Polic , Wolfgang Förstner , Tomas Pajdla

We propose Fourier transform (FT) method for processing images of extensive air showers (EAS) detected by imaging atmospheric Cherenkov telescopes (IACT) used in the very high energy (VHE) gamma-ray astronomy. The method is based on the…

Astrophysics · Physics 2009-11-10 A. Atoyan , J. Patera , V. Sahakian , A. Akpherjanian

Image or object recognition is an important task in computer vision. With the hight-speed processing power on modern platforms and the availability of mobile phones everywhere, millions of photos are uploaded to the internet per minute, it…

Computer Vision and Pattern Recognition · Computer Science 2017-06-06 Yong Khoo , Seo-hyeon Keun

Fourier ptychography (FP) is a powerful light-based synthetic aperture imaging technique that allows one to reconstruct a high-resolution, wide field-of-view image by computationally integrating a diverse collection of low-resolution,…

Image and Video Processing · Electrical Eng. & Systems 2025-07-21 Matthew A. Chan , Casey J. Pellizzari , Christopher A. Metzler

State-of-the-art image-set matching techniques typically implicitly model each image-set with a Gaussian distribution. Here, we propose to go beyond these representations and model image-sets as probability distribution functions (PDFs)…

Computer Vision and Pattern Recognition · Computer Science 2015-08-03 Mehrtash Harandi , Mathieu Salzmann , Mahsa Baktashmotlagh

We implement the Fourier shape parametrization within the point-coupling covariant density functional theory to construct the collective space, potential energy surface (PES), and mass tensor, which serve as inputs for the time-dependent…

Nuclear Theory · Physics 2025-03-13 Zeyu Li , Yang Su , Lile Liu , Yongjing Chen , Zhipan Li

The technologically-relevant task of feature extraction from data performed in deep-learning systems is routinely accomplished as repeated fast Fourier transforms (FFT) electronically in prevalent domain-specific architectures such as in…

Digital aberration measurement and removal play a prominent role in computational imaging platforms aimed at achieving simple and compact optical arrangements. A recent important class of such platforms is Fourier ptychography, which is…

To obtain the initial pressure from the collected data on a planar sensor arrangement in photoacoustic tomography, there exists an exact analytic frequency domain reconstruction formula. An efficient realization of this formula needs to…

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