Mechanism for registering digital images obtained from multiple sensors

Abstract

First and second digital images, such as terrestrial images captured by one or more spaceborne or airborne sensors, are transformed onto a registration surface in accordance with geometry models of the sensors, to bring the digital images into mutual alignment on the registration surface. The images are initially subsampled to obtain reduced spatial resolution versions of each image. For a base resolution version of each image, respective neighborhoods of pixels associated with matching point grids in each image are defined. Edge-preemphasized contents of respective neighborhoods of pixels of each image are cross-correlated with one another, to derive a measure of misregistration between the images. One or both of the geometry models of the sensors are modified in accordance with the measure of misregistration, so as to effectively decrease misregistration between the images on the registration surface. The neighborhood cross-correlation process is then repeated for increasingly higher spatial resolution versions of each image, to effect a coarse-to-fine improvement in registration error correction.