Fourier difference-image subsampling

FOURIER DIFFERENCE-IMAGE SUBSAMPLING 5 Disclosed is a method (200) for registering two input images (100, 105; 110, 115). The method determines (220) a Fourier transform of each of the two images and combines (230) the determined Fourier transforms into a correlation Fourier transform. The correlation Fourier transform is resized (250) down to form a scaled down correlation Fourier transform encoded with a registration peak. The method then determines one or 10 both of a position (540) and a magnitude value (520) associated with the registration peak encoded in the scaled down correlation Fourier transform, and registers the two images based on the determined one or both of the position value and magnitude value associated with the registration peak. P019398_speci-lodge m ~ 800 Image 1 0 [ 0 Image 2 Transform Transform of image 1 of image 2 Combined spectrum Downsampled spectrum Inverse transform containing peak Fig. 8 P01 9398_figslodge