Accurate Registration of Multitemporal UAV Images Based on Detection of Major Changes

Accurate registration of multitemporal images captured by UAV usually involves affine transformation and complicated non-rigid transformation, which makes it very difficult to achieve satisfying results. Pixel-wise correspondence is effective for handling images with complicated non-rigidity. However, objects with changes in the scene deform severely because there should be no pixel-wise correspondence but the algorithm erroneously matches the pixels. In this paper, we propose a coarse-to-fine registration method for multitemporal UAV images. First, a projective model is used to eliminate large scale changes as well as perspective distortion. Then the major changes of different temporal UAV images are most detected, which is used to mask the dense matches in changed areas. Finally, the optical flow field method is used to handle complicated non-rigid changes by matching dense SIFT feature. Experimental results on a challenging set of multitemporal UAV images demonstrate the effectiveness of our approach.