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Title: Non-stationary Structure-Preserving Preconditioning for Image Restoration
Non-stationary regularizing preconditioners have recently been proposed for the acceleration of classical iterative methods for the solution of linear discrete ill-posed problems. This paper explores how these preconditioners can be combined with the flexible GMRES iterative method. A new structure-respecting strategy to construct a sequence of regularizing preconditioners is proposed. We show that flexible GMRES applied with these preconditioners is able to restore images that have been contaminated by strongly non-symmetric blur, while several other iterative methods fail to do this.  more » « less
Award ID(s):
1720259 1729509
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Computational Methods for Inverse Problems in Imaging
Medium: X
Sponsoring Org:
National Science Foundation
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