A method of obtaining gray balance data based on polynomial regression

摘要

As gray balance is very important for color separation and printing quality control, a method based on polynomial regression is proposed to determining the gray balance data in printing process. Firstly the patches on GrayFinder target of GRACoL proof are measured and the L*a*b* values are obtained, then the relationship between L*a*b* and CMY is determined by using the polynomial regression method, at last the different lightness' corresponding CMY values are found which constitute the gray balance data by using the relationship obtained above. In the experiment, 8 gray patches are used to test the algorithm, and the result shows the average error is 0.969 with the maximal error 2.047 which indicates that the method can be used to find gray balance data.