EURASIP Journal on Applied Signal Processing 
Volume 2004 (2004), Issue 16, Pages 2462-2475
doi:10.1155/S1110865704404132

Blind Image Deblurring Driven by Nonlinear Processing in the Edge Domain

Stefania Colonnese,1 Patrizio Campisi,2 Gianpiero Panci,1 and Gaetano Scarano1

 1Dipartimento Infocom, Università degli Studi di Roma “La Sapienza”, Via Eudossiana 18, Roma 00184, Italy
2Dipartimento Elettronica Applicata, Università degli Studi “Roma Tre”, Via Della Vasca Navale 84, Roma 00146, Italy
Received 2 September 2003; Revised 20 February 2004

Abstract

This work addresses the problem of blind image deblurring, that is, of recovering an original image observed through one or more unknown linear channels and corrupted by additive noise. We resort to an iterative algorithm, belonging to the class of Bussgang algorithms, based on alternating a linear and a nonlinear image estimation stage. In detail, we investigate the design of a novel nonlinear processing acting on the Radon transform of the image edges. This choice is motivated by the fact that the Radon transform of the image edges well describes the structural image features and the effect of blur, thus simplifying the nonlinearity design. The effect of the nonlinear processing is to thin the blurred image edges and to drive the overall blind restoration algorithm to a sharp, focused image. The performance of the algorithm is assessed by experimental results pertaining to restoration of blurred natural images.