1. A CT system comprising: a rotatable gantry having an opening for receiving an object to be scanned; an x-ray source coupled to the gantry and configured to project x-rays through the opening; a generator configured to energize the x-ray source to a first kilovoltage (kVp) and to a second kVp to generate the x-rays; a detector having pixels therein, the detector attached to the gantry and positioned to receive the x-rays; and a computer programmed to: acquire a first view dataset with the x-ray source energized to the first kVp and a second view dataset with the x-ray source energized to the second kVp; generate a base correction image using the first view dataset and the second view dataset; reconstruct a pair of base material images from the first view dataset and from the second view dataset; estimate artifact correlation in the pair of base material images using the base correction image; generate a pair of final base material images and a final monochromatic image; and correct one of the pair of final base material images and the final monochromatic image at a keV value using the estimated artifact correlation.