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(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Image Restoration Using Gradient Iteration and Constraints for Band Extrapolation

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Author(s):
Ponti, Moacir [1] ; Helou, Elias S. [1] ; Ferreira, Paulo Jorge S. G. [2] ; Mascarenhas, Nelson D. A. [3]
Total Authors: 4
Affiliation:
[1] Univ Sao Paulo, ICMC, BR-13566590 Sao Carlos, SP - Brazil
[2] Univ Aveiro, DETI IEETA, P-3810913 Aveiro - Portugal
[3] Fac Campo Limpo Paulista FAC CAMP, BR-13231230 Campo Limpo Paulista, SP - Brazil
Total Affiliations: 3
Document type: Journal article
Source: IEEE JOURNAL OF SELECTED TOPICS IN SIGNAL PROCESSING; v. 10, n. 1, p. 71-80, FEB 2016.
Web of Science Citations: 4
Abstract

Images obtained with optical microscopes are often blurred and corrupted by noise. Specially in wide-field microscopy, there is a strong out-of-focus blur in focal plane direction, caused mainly by a frequency loss in the acquisition process. In order to restore these images it is important to use non-linear methods and relevant prior knowledge as constraints. In this paper, we propose a projection onto convex sets framework using a sequence of prototype images inspired by the Richardson-Lucy iterative algorithm. Within this framework it is possible to use constraints while restoring the image, during the iterations. We prove that the iterative method can be implemented as a gradient iteration, followed by a sequence of projections onto constraint sets. Moreover, we performed experiments using the techniques in order to improve restoration. The results showed a better restoration of frequencies, an improved focal plane restoration and a better contrast when compared with the regular iterative restoration algorithm. (AU)

FAPESP's process: 11/22749-8 - Challenges in exploratory visualization of multidimensional data: paradigms, scalability and applications
Grantee:Luis Gustavo Nonato
Support type: Research Projects - Thematic Grants
FAPESP's process: 13/07375-0 - CeMEAI - Center for Mathematical Sciences Applied to Industry
Grantee:José Alberto Cuminato
Support type: Research Grants - Research, Innovation and Dissemination Centers - RIDC
FAPESP's process: 13/16508-3 - Fast computation of the generalized Backprojection operator with applications in tomographic image reconstruction
Grantee:Elias Salomão Helou Neto
Support type: Regular Research Grants