1. A system for correcting pattern noise projection images comprising: means for acquiring a set of projection images, where each of the set of projection images is acquired at a different angle of view; means for thresholding each projection to produce a set of threshold images, where the thresholding means is coupled to receive the set of projection images; means for summing the set of threshold images to form an ensemble image, where the summing means is coupled to receive the set of threshold images; means for processing each of the set of threshold images to produce a set of binary images, where the binary processing means is coupled to receive the set of threshold images; means for summing the set of binary images to form an ensemble mask, where the summing means is coupled to receive the ensemble mask; means for dividing the ensemble image by the ensemble mask to yield a background pattern noise image, where the dividing means is coupled to receive the ensemble image and the ensemble mask; means for multiplying each projection image by a scaling factor and dividing by the background pattern noise to produce a quotient image, where the multiplying means is coupled to receive each projection image and the background pattern noise; and means, coupled to receive the quotient image, for filtering the quotient image to produce a noise corrected projection image.