Eastman Kodak Company
Correcting tone scale errors in a digital printer

Abstract:

A method for correcting tone-level non-uniformities in a digital printing system includes printing a test target having a set of uniform test patches. The printed test target is automatically analyzed to determine tone-level errors as a function of cross-track position for each of the test patches. A tone-level correction function is determined and represented using a set of one-dimensional feature vectors which specifies tone-level corrections as a function of cross-track position and pixel value. Corrected image data is determined by using the tone-level correction function to determine a tone-level correction value for each image pixel responsive to the input pixel value and cross-track position of the image pixel. The corrected image data is printed using the digital printing system to provide a printed image with reduced tone-level errors.