Title :
Variational Justification of Cycle Spinning for Wavelet-Based Solutions of Inverse Problems
Author :
Kamilov, Ulugbek S. ; Bostan, Emrah ; Unser, Michael
Author_Institution :
Biomed. Imaging Group, Ecole Polytech. Fed. de Lausanne (EPFL), Lausanne, Switzerland
Abstract :
Cycle spinning is a widely used approach for improving the performance of wavelet-based methods that solve linear inverse problems. Extensive numerical experiments have shown that it significantly improves the quality of the recovered signal without increasing the computational cost. In this letter, we provide the first theoretical convergence result for cycle spinning for solving general linear inverse problems. We prove that the sequence of reconstructed signals is guaranteed to converge to the minimizer of some global cost function that incorporates all wavelet shifts.
Keywords :
inverse problems; signal reconstruction; variational techniques; wavelet transforms; cycle spinning; general linear inverse problems; global cost function; reconstructed signal sequence; recovered signal quality; variational justification; wavelet shifts; wavelet-based solutions; Convergence; Image reconstruction; Inverse problems; Spinning; Standards; TV; Wavelet transforms; Cycle spinning; linear inverse problems; wavelet regularization;
Journal_Title :
Signal Processing Letters, IEEE
DOI :
10.1109/LSP.2014.2334306