Patent ID: 7639410

Claim:
A method of selecting optimal color test patches for an image: rendering system, the method comprising: (a) initializing a set of values, where the set of values includes N number of colors used for calibration of the image rendering system, a computational tolerance number, and a delta-E tolerance number; (b) printing M colors and collecting data over a drift space; (c) forming by a controller, a color-drifting data matrix P and performing singular value decomposition of the covariance matrix formed by the color-drifting data matrix P to determine the eigen functions; (d) determining the number of color eigenvectors that are required based on a delta-E curve and the delta-E tolerance number; (e) where M!/N!(M−N)! is greater than the computational tolerance number, selecting a plurality of components with the largest values from each color eigenvector and computing J 1 ; (f) computing J 2 by minimizing J 1 further; (g) where J 2 <J 1 , selecting N colors from step (f) as the optimal color test patches; and (h) where J 2 ≧J 1 , selecting N colors from step (e) as the optimal color test patches.