IMAGE PROCESSING APPARATUS, CONTROL METHOD, PROGRAM, AND STORAGE MEDIUM

摘要

PROBLEM TO BE SOLVED: To use digital watermark image data when subsequently restoring color image data that has been output as monochromatic image data, and reduce the data amount of the digital watermark image data. SOLUTION: An image forming apparatus generates digital watermark image data using color-difference data of the color-difference data and luminance data. The luminance data are not included in the digital watermark image data. If the luminance data are included in the digital watermark image data, the luminance data have been reduced at a very high reduction ratio before being included thereinto. COPYRIGHT: (C)2008,JPO&INPIT