Abstract

In order to investigate the deep structure of Gaussian scale space im- ages, one needs to understand the behaviour of spatial critical points under the infiuence of blurring. We show how the mathematical framework of catastrophe theory can be used to describe the behaviour of critical point trajectories when various different types of generic events, viz. annihilations and creations of pairs of spatial critical points, (almost) coincide. Although such events are non-generic in mathematical sense, they are not unlikely to be encountered in practice. Further- more the behaviour leads to the observation that fine-to-coarse tracking of critical points doesn’t suffice. We apply the theory to an artificial image and a simulated MR image and show the occurrence of the described behaviour.