Patent ID: 7418129

Claim:
An image-processing apparatus for adjusting gradation of image signals, comprising: gradation-correction means for generating a corrected value by correcting gradation of a value of a first element out of first to third elements according to a first color system, the value of the first element being defined by the input image signals; first calculating means for calculating values of fourth to sixth elements according to a second color system, based on values of the first to third elements according to the first color system, the values of the first to third elements being defined by the input image signals; second calculating means for calculating values defined by seventh and ninth elements according to a third color system represented by the seventh to ninth elements, based on the values of the fourth to sixth elements calculated by the first calculating means; and third calculating means for calculating values of the fourth to sixth elements according to the second color system, based on the value of the fourth element according to the second color system and the values that are calculated by the second calculating means and defined by the seventh and ninth elements according to the third color system.