阐述了基于DCT变换域的数字水印理论和算法，并根据相关理论模型，提出了一种在离散傅里叶变换中实现的、可用于印刷品防伪的数字水印嵌入算法。研究表明与传统的LSB算法和Patchwork算法相比，该算法有较好的抗攻击能力。给出了系统的水印嵌入算法和水印提取流程设计的过程。实践证明，基于DCT变换域的数字水印算法能确保水印的不可见性，并保持较好的鲁棒性，实现了印刷图像载体数字版权的保护，并可检测出用此算法嵌入印刷图像中的不可见标记。最后通过实验验证了此算法的可行性、可靠性和有效性，为印刷品版权保护提供参考和借鉴。

The theory and algorithm of digital watermarking based on DCT transform domain was introduced. A kind of digital watermarking imbedded algorithm realized in discrete Fourier Transform was proposed based on the related theoretical models, which could be used anti-counterfeiting of printed materials. Study results showed that this algorithm has better anti-attack ability than traditional LSB algorithm and Patchwork algorithm. Systematic watermark imbedded algorithm and watermark extraction procedure design were given. Practice proved that digital watermark algorithm based on DCT transform domain can ensure the invisibility of the watermark and the good robustness, which can realize digital copyright protection for printed image carriers and can detect the invisible mark imbedded in printed images by this method. The experiments verified the feasibility, reliability and effectiveness of this method. The purpose was to provide reference for copyright protection of printed materials.