在印刷CMYK颜色空间、傅里叶全息加密和数字水印理论的基础上，提出了基于CMYK颜色空间的光全息水印算法。该算法不用转换颜色空间，避免了未印刷就人为导致水印信息的丢失，提高了重建水印的相似度；解密时，由于傅里叶变换的特性，重建水印的共轭图像与原水印图像互相叠加，增强了重建水印的清晰度。实验结果表明，该算法有较好的不可见性和较强鲁棒性，可以抵抗一般图像处理等操作。

A light holographic watermarking algorithm based on CMYK color space was put forward based on CMYK color space, Fourier hologram encryption, and digital watermarking theory. The algorithm without color space conversion avoids losing watermark before printing and improving the similarity of the reconstructed watermark; due to the characteristics of the Fourier transform, overlaying the conjugate image of the reconstructed watermark and the original watermark image can increase definition of reconstructed watermark when decrypted. Experimental results showed that the algorithm has good invisibility and strong robustness and is able to resist general image processing operations.