[2407. 06834] Efficient nonlocal linear image denoising . . . A critical bottleneck when solving such problems for finely-resolved images is the solution of huge-scale, dense linear systems arising from the minimization of an energy term We tackle this using a Krylov subspace approach, with a Nonequispaced Fast Fourier Transform utilized to approximate matrix-vector products in a matrix-free manner
Using NFFT 3---A Software Library for Various Nonequispaced . . . NFFT 3 is a software library that implements the nonequispaced fast Fourier transform (NFFT) and a number of related algorithms, for example, nonequispaced fast Fourier transforms on the sphere and iterative schemes for inversion This article provides
Using NFFT 3 { a software library for various nonequispaced . . . NFFT 3 is a software library that implements the nonequispaced fast Fourier transform (NFFT) and a number of related algorithms, e g nonequispaced fast Fourier transforms on the sphere and iterative schemes for inversion This is to provide a survey on the mathematical concepts
Fast Fourier transforms for nonequispaced data: a tutorial By employing nonequispaced fast Fourier transform, our approaches significantly reduce the arithmetic operations to compute the distances from $\mathcal O(n^2)$ to $\mathcal O(n\log n)$, which