中文摘要：

【摘要】CMYK印刷图像数字水印所面临的主要挑战是抵抗印刷扫描过程的鲁棒性和水印对印刷图像颜色保真度的影响。该文基于CMYK颜色空间的再现特征和人眼视觉特点，提出在图像的Y色信息通道和Kg信息通道中分别嵌入有意义水印和结构模板信号。为了提高印刷图像的颜色保真度，基于人眼视觉特征建立了视觉蒙版，并在图像的空间域中对水印信号进行重塑，以胶版印刷为工业应用背景进行了一系列实验测试。实验结果表明本文提出的面向保真印刷的cMYK图像鲁棒水印方法，适用于以胶版印刷方式为应用背景的CMYKIN像保真复制，在实际应用中具有较好的有效性。

英文摘要：

The challenges faced with printed image watermarking applications mainly are the robustness against distortion caused by print-scanning processing and the color fidelity of primed images. Based on the feature of CMYK color space and human visual system, this paper presents a robust CMYK primed image watermarking, which embeds the informative watermark and the structure template signal respectively in the Y color information channel and K color information channel. The embedded template enables the necessary robustness against geometric distortions in print-scanning process. A spatial perceptual mask is used to reshape the embedded energy after it is inverted to the spatial domain, which significantly improves the color fidelity and the image quality. A series of proof tests have been carried out on lithographic printing presses and shows that the watermark embedded in the CMYK images is well preserved and can be extracted with a high quality, and simultaneously, a remarkable fidelity of color and tones on printed copies is also well preserved.