Local-global optical flow for image registration agents

Registration is a fundamental task in image processing used to match two or more images taken, for example, at different times, from different sensors, or from different viewpoints. Optical flow is a technique in computer vision area to compute the displacement field of the contents within an image sequence. In the sense of correspondence, image registration and optical flow have very close relation. On the one hand, optical flow is used to do image registration; on the other hand, it is also used to evaluate the performance of image registration. In literature, either local optical flow or global optical flow is studied for image registration. In this paper, an improved optical flow technique, namely Local-Global, which combines the advantages of both techniques, is applied for image registration. Experiments are conducted to demonstrate the effectiveness of this method.