Multi-focus image registration based on optical flow tracking and Delaunay triangulation

In the fields of multi-focus image fusion and shape from focus, accurate registration of multi-focus images is a crucial prerequisite. Due to the difficulty of feature detection in defocused regions and the limitations of global registration methods, traditional multi-focus image registration methods have low accuracy. To solve this problem, a novel multi-focus image registration method based on optical flow tracking and Delaunay triangulation is proposed. The innovation includes two aspects. The first is that optical flow tracking is utilized to extract and match the non-salient features of multi-focus images. It greatly increases the number of matching features in the defocused regions of multi-focus images. The second is that Delaunay triangulation is adopted for local registration. It makes the matching features strictly aligned. The results of the experiments show that the proposed method is superior to the traditional methods in terms of image registration accuracy and image fusion quality.