1. A method of determining location of a target image within a two-dimensional input image by employing a three-dimensional reference model, the method comprising the steps of: extracting object edge points in the input image; given estimated seeker line-of-sight orientation and range data, projecting a three-dimensional target reference model to obtain a two-dimensional reference image; applying a weighted-direction-cross-product Hough Transform to the object edge points and points of the two-dimensional reference image; classifying the input image as containing a target image or not; if the input image contains the target image, identifying a location of the target image within the two-dimensional input image; computing confidence measure as to the identified location of the target image within the two-dimensional input image; and performing confidence accumulation over a plurality of instances of application of the method.