A diagnostic imaging system in an example comprises a high frequency electromagnetic energy source, a detector, a data acquisition system (DAS), and a computer. The high frequency electromagnetic energy source emits a beam of high frequency electromagnetic energy toward an object to be imaged and be resolved by the system. The detector receives high frequency electromagnetic energy emitted by the high frequency electromagnetic energy source. The DAS is operably connected to the detector. The computer is operably connected to the DAS and programmed to employ an inversion table or function to convert N+2 measured projections at different incident spectra into material specific integrals for N+2 materials that comprise two non K-edge basis materials and N K-edge contrast agents. N comprises an integer greater than or equal to 1.