Robust multi-scale multi-modal image registration

Abstract

Multi modal image registration is an especially difficult problem when one of the images contains only a small region of the other image. In this case there is generally a need to search for the alignment parameters over the entire image. If an associated local optimization scheme is initialized far from the global solution, it usually converges to a local optimum. This paper presents a multi-scale approach that greatly enlarges the basin of attraction of the global optimum, and demonstrates how to find the correct solution to the optimization problem efficiently and reliably, by solving a small number of local optimization problems and tracking a small number of likely candidates.