Patent ID: 7466857

Claim:
An image processing method for correcting pixel values of each pixel constituting color image data by shifting, in a coordinate system, a mathematical correction function defining correction values for input values, the method comprising the computer-implemented steps of: determining a maximum value and a minimum value among correction values (b, g, r) of respective color components obtained for each pixel by using said correction function, calculating differences (Δb, Δg, Δr) between the respective correction values of the respective color components and said minimum value, and calculating a difference (DR) between said maximum value and said minimum value; dividing said calculated differences (Δb, Δg, Δr) between the respective correction values of the respective color components and said minimum value by said calculated difference (DR) between said maximum value and said minimum value, thereby to obtain color ratios (Cb, Cg, Cr) for the respective color components; determining, as an inappropriate pixel, any pixel having a correction value overflowing from a predetermined maximum output gradation value and setting said overflowing correction value to said predetermined maximum output gradation value and determining, as an inappropriate pixel, any pixel having a correction value underflowing from a predetermined minimum output gradation value and setting said underflowing correction value to said predetermined minimum output gradation value; and controlling color balance adjustment so as to cause the correction values of said inappropriate pixel to agree with said respective color ratio thereof.