Acceleration of RED via Vector Extrapolation

TL;DR

This paper introduces a vector extrapolation method to accelerate RED algorithms for inverse problems, significantly reducing computation time while maintaining solution quality.

Contribution

The paper proposes a novel acceleration technique using vector extrapolation to speed up RED-based inverse problem solvers.

Findings

VE significantly reduces computation time.

VE maintains solution accuracy.

Numerical experiments confirm efficiency gains.

Abstract

Models play an important role in inverse problems, serving as the prior for representing the original signal to be recovered. REgularization by Denoising (RED) is a recently introduced general framework for constructing such priors using state-of-the-art denoising algorithms. Using RED, solving inverse problems is shown to amount to an iterated denoising process. However, as the complexity of denoising algorithms is generally high, this might lead to an overall slow algorithm. In this paper, we suggest an accelerated technique based on vector extrapolation (VE) to speed-up existing RED solvers. Numerical experiments validate the obtained gain by VE, leading to a substantial savings in computations compared with the original fixed-point method.