Spectrum reflectance ratio presumption manner, from the graphics data which includes the image of spectrum reflectance ratio presumption target

摘要

PPROBLEM TO BE SOLVED: To highly accurately estimate a colorimetry value of an estimating object for reproduction of its color under desired light sources. PSOLUTION: A method comprises the steps of acquiring image data of a color chart when inputting a standard plate having a color chart different in spectral reflectance by the same image inputting condition as the estimating object for reproduction of its color; executing an optimization method using induced variables extracting a sensor response value corresponding to each color chart from the image data, independent variables produced from spectral reflectance of each color chart, and basis function which expresses the spectral reflectance by linear coupling in a specific dimension; producing a conversion factor for converting a factor relating to the basis function for expressing the spectral reflectance of the object by the linear coupling of the specific dimension into the sensor response value of the image input device; calculating a candidate of the spectral reflectance corresponding to the sensor response value, based on the conversion factor and the basis function for expressing the spectral reflectance of the object by the linear coupling of the specific dimension; and deciding a spectral reflectance candidate with maximum existence probability factor by the optimization method. PCOPYRIGHT: (C)2007,JPO&INPIT