Patent ID: 7974466

Claim:
A method for obtaining a target color measurement using an electronic image capturing device having a plurality of reference colors and light and dark level correction references, comprising the steps of: as a set up step, before measuring a target color: determining a field correction array by placing an identical color reference in each of a plurality of locations in the field of the image capturing device and computing a field correction array; and determining a level correction vector using the light and dark level correction references wherein the level correction vector is determined based upon a predicted value of red, green and blue intensities for each of the level correction references; and each time a target color is measured using the image capturing device: determining a color correction matrix under the conditions extant at the time that the target color is measured using the image capturing device based on the field correction array and the level correction vector; and determining a calibration correction under the conditions extant at the time that the target color is measured by application of the field correction array and the level correction vector determined in the set up step and application of the color correction matrix to the light and dark reference colors; and adjusting a target color measurement obtained using the electronic image capturing device based upon the color correction matrix, and the calibration correction to obtain a corrected color target measurement.