Abstract: A robust watermarking technology with high transparency is proposed in this paper.It improves the method of embedding watermark by adopting EMD technology.The proposed method provides high embedding efficiency that is better than previous watermarking technologies.The high efficiency of embedding makes the scheme obtain a great balance which is very robust with high transparency.The scheme enables to resist on all kinds of unintentional or intentional attacks especially on Internet.It is a half-blind watermarking method without needing of origin watermark’s participation in the process of extraction.The visual system of human being is introduced in this method to improve the invisibility of watermarks.The results of experiments prove that the arithmetic has great advantages comparing with others watermarking technologies.

Key words: watermarking, robustness, transparency, half-blind detecting, encrypted document

摘要： 提出了一种拥有强稳健性同时可以兼顾高透明性的数字水印技术。它通过对水印嵌入方式的巧妙修改，实现了水印的稳健性和透明性这对原本相互矛盾的性质彼此兼容存在。水印的嵌入算法基于人类视觉模型基础之上，利用人眼对图像细微变化的无法察觉性，采用了巧妙的嵌入算法在保证了一定嵌入信息量的基础上有效地降低了对图像数据的实际修改率。这就使得水印不仅拥有了强稳健性，而且使由水印嵌入所带来的图像质量损失降到了最低，从而有力地保证了水印的透明性。这一算法不仅可以有效地应对各种常规的信号处理攻击，而且还可以防止大部分的恶意水印攻击。同时算法的抽取和检测不需要原始水印的参与，是一种半盲水印算法。最后的实验部分证实了该算法相比于其他多种同类型水印算法，稳健性和透明性都有明显提高。

关键词: 数字水印, 水印稳健性, 水印透明性, 半盲检测, 加密存储文档