Nonmonotone and Monotone Active-Set Methods for Image Restoration, Part 2: Numerical Results

Active-set methods based on augmented Lagrangian smoothing of nondifferentiable optimization problems arising in image restoration are studied through numerical experiments. Implemented algorithms for solving both one-dimensional and two-dimensional image restoration problems are described. A new, direct way for solving the constrained optimization problem appearing in the inner iteration of the monotone algorithms is presented. Several numerical examples are included.