Image Number 15 for United States Patent #7433102.
A primary color dot gain correction unit corrects the spectral reflectance of each of a plurality of color agents on the basis of the dot quantity set for each color agent. An initial estimated value calculator estimates a mixed color by the KM theory using spectral reflectance data corrected by the primary color dot gain correction unit. An ink overlap correction coefficient storage unit stores correction coefficients, which are determined on the basis of errors between the actually measured values of spectral reflectance data of color patches obtained using the plurality of color agents, and estimated values estimated by the initial estimated value calculator based on the dot quantities of the respective color agents on the color patches. An ink overlap correction unit obtains the prediction result of a reproduction color by correcting the spectral reflectance data of the mixed color calculated by the initial estimated value calculator on the basis of the correction coefficients stored in the ink overlap correction coefficient storage unit.