Patent ID: 6961066
Filing Date: 2005-11-01
Classification: G06T,G09G

Abstract:
1. A method for automatic adjustment of the color of a digital original image for forming a digital adjusted image, the original image being a whole of a supplied digital image or a portion thereof and being formed of a plurality of color dots, each dot having at least three independent values representing the strength of the three primary colors R, G, and B, each strength value lying between a minimum and a maximum of a dynamic range, comprising: determining an original dot maximum of the R, G, or B strength values in RGB color space for each color dot within the original image for establishing an original histogram of original dot maximums for the plurality of color dots within the original image; establishing an original average strength of the original histogram; amplifying each of the original dot maximums by selecting a correcting scaling factor from a continuous scaling function and applying the correcting scaling factor for each original dot maximum which scales the original dot maximum to a scaled dot maximum which is less than or equal to the maximum of the dynamic range; establishing a corrected average strength of the original dot maximums from a corrected histogram of the scaled dot maximums; comparing the original average strength to a target average strength; determining an interpolation constant between an identity scaling factor of 1 and the correcting scaling factor for each original dot maximum by interpolation using the target average strength, the corrected average strength and the original average strength for each dot maximum; and creating an adjusted image without color distortion by applying the interpolation constant to modify the correcting scaling factor for each original dot maximum and establishing a target scaling factor which is applied to each color dot's R, G and B strength values so that a histogram of the adjusted image has the target average strength and that the ratios of the strength values between R, G and B for the color dot remain the same after scaling as they were before scaling.