Mathematics – Optimization and Control
Scientific paper
2010-01-13
Mathematics
Optimization and Control
12 pages, 12 figures, 2 tables. Submitted to the IEEE Transactions on Image Processing
Scientific paper
Much research has been devoted to the problem of restoring Poissonian images, namely for medical and astronomical applications. However, the restoration of these images using state-of-the-art regularizers (such as those based on multiscale representations or total variation) is still an active research area, since the associated optimization problems are quite challenging. In this paper, we propose an approach to deconvolving Poissonian images, which is based on an alternating direction optimization method. The standard regularization (or maximum a posteriori) restoration criterion, which combines the Poisson log-likelihood with a (non-smooth) convex regularizer (log-prior), leads to hard optimization problems: the log-likelihood is non-quadratic and non-separable, the regularizer is non-smooth, and there is a non-negativity constraint. Using standard convex analysis tools, we present sufficient conditions for existence and uniqueness of solutions of these optimization problems, for several types of regularizers: total-variation, frame-based analysis, and frame-based synthesis. We attack these problems with an instance of the alternating direction method of multipliers (ADMM), which belongs to the family of augmented Lagrangian algorithms. We study sufficient conditions for convergence and show that these are satisfied, either under total-variation or frame-based (analysis and synthesis) regularization. The resulting algorithms are shown to outperform alternative state-of-the-art methods, both in terms of speed and restoration accuracy.
Bioucas-Dias José M.
Figueiredo Mário A. T.
No associations
LandOfFree
Restoration of Poissonian Images Using Alternating Direction Optimization does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Restoration of Poissonian Images Using Alternating Direction Optimization, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Restoration of Poissonian Images Using Alternating Direction Optimization will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-526006