Sub-pixel image registration based on physical forces

A new method for image registration has been previously proposed by the authors, which the registration is based on physical forces. The registration parameters are translation and rotation. This method assumes images like charged materials that attract each other. In this case, one of the images moves in the same direction as the applied force while the other one is still. The movement of the image continues until the resultant force becomes zero. This approach estimates the registration parameters simultaneously and leading to a better optimized set of registration parameters. The registration error for this method is 1 to 3 pixels. In this paper we aim to develop this method for the applications which need sub-pixel accuracy. First, by applying the Canny edge detector on the input images, the edge information is also used for the registration process to increase the robustness of this method in the presence of noise. After that, sub-pixel accuracy is provided for this method by using interpolation techniques.