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An extension to the basic concept of correlation detection as a means of image registration is developed. The technique involves linear spatial preprocessing of the inages to be registered prior to the application of a correlation measure. This preprocessing operation utilizes the spatial correlation within each image and greatly improves the detectability of image misregistration. An analysis of the computational aspects of the algorithm is given. Also, results of a computer simulation to evaluate the technique are given.In many image processing applications it is necessary to form a pixel-by-pixel comparison of two images of the same object field obtained from different sensors, or of two images of an object field taken from the same sensor at different times. To form this comparison it is necessary to spatially register the images and thereby correct for relative translational shifts, magnification differences, and rotational shifts, as well as goemetrical and intensity distortions of each image. Often it is possible to eliminate or minimize many of these sources of misregistration by proper static calibration and compensation of the image sensor; in some applications misregistration detection and subsequent correction must be performed dynamically for each pair of images.Consideration is given here to the single problem of registering images subject to translational differences. The results can be applied to the detection of rotational and magnification differences by increasing the dimensionality of the problem, or by a proper transformation of coordinates (e.g., a rotational shift is equivalent to a translational shift in polar coordinates).