Performance comparison of holographic watermarking for color images in RGB and CMYK channels

The color space of watermarked images is to be converted from RGB to CMYK for anti-counterfeited print media, which is to lead watermarked images distortion. For this reason, a holographic watermarking scheme for print images in CMYK was presented. Print-scanning experiment was done to verify the feasibility of this scheme by printer instead of printing machine and to compare the watermarking qualities in different channels of CMYK and RGB using PSNR and NC. The results demonstrated the feasibility of this watermarking, and its watermarking quality was almost same to the one in RGB.