Patent ID: 8422084

Claim:
An image processing apparatus comprising: a spectral reflectance calculation unit that respectively calculates m spectral reflectances in a plurality of wavelength ranges, based on intensity of light reflected from an object to be imaged and based on irradiation intensity of light that the object to be imaged is irradiated with; a determination unit that obtains a derivative value by differentiating with respect to a wave a function that is obtained on the basis of the m spectral reflectances, and represents a relationship between the spectral reflectances and the wavelength ranges, and determines, as a number of eigenvectors, a number equal to or greater than a number of wavelengths in which the derivative value changes from a positive value to a negative value or from a negative value to a positive value, and smaller than m; a coefficient calculation unit that calculates, using a CPU, coefficients where the spectral reflectances are expressed by linear combination of the number of eigenvectors and the coefficients respectively related to the eigenvectors, the number of eigenvectors being determined by the determination unit; and an output unit that outputs the coefficients calculated by the coefficient calculation unit.