Operations Research: Geovani Nunes Grapiglia

Improved Optimization Methods for Image Registration Problems

Geovani Nunes Grapiglia, Federal University of Paraná

In many applications, multiple images of the same subject are obtained at different moments in time and under different conditions. The goal is to identify changes in the subject over time. For a fair comparison, the images need to be aligned in order to overlap the common features. Image Registration is the problem to find the transformation of images leading to the best overlapping. The mathematical modelling of this type of problem often results in large-scale unconstrained optimization problems to solve. The usual approach is to apply Gauss-Newton Method with Armijo line-search embedded in a multi-level coarse-to-fine scheme, where the solution of the coarse level is used to generate the initial point for the fine level. In this talk, two alternative approaches will be discussed, including the use of L-BFGS and subspace techniques