Patent ID: 7070252
Filing Date: 2006-07-04
Classification: B41J,H04N

Abstract:
1. An encoding method for digital watermarking in a calibrated printing path, comprising: (a) receiving a pixel having cyan, magenta, and yellow color values representing an input image; (b) receiving, for each received pixel having cyan, magenta, and yellow color values representing an input image, a plurality of information bits, the plurality of information bits representing data to be encoded at a corresponding pixel in an output image; (c) selecting a gray component replacement function from a predetermined number of different gray component replacement functions, for each received pixel, based upon the received information bits for the received pixel; (d) generating cyan, magenta, yellow and black output values for the received pixel using the selected gray component replacement function and the cyan, magenta, and yellow color values of the received pixel, the generated black output value representing the data to be encoded at the corresponding pixel in the output image; and (e) assigning the cyan, magenta, yellow and black output values to the corresponding pixel in the output image.