Image processing apparatus, image forming apparatus, methods of controlling image processing apparatus and image forming apparatus to reconstruct an electronic color image from a printed color image

摘要

A color printed image with compressed colors produced by printing an electronic color image is reconstructed into an electronic color image similar to an original color image by using digital watermark image data with a reduced data size. The digital watermark image data is produced using color difference data of the color image data including luminance data and the color difference data. The digital watermark image data either does not include luminance data or includes luminance data with a data size reduced at a very large ratio.