鲁棒性数字图像水印技术

Robust Digital Image Watermarking Technique

数字水印技术作为版权保护的重要手段已经成为了研究的热点,但是实用的鲁棒性数字水印技术不多,特别是抗几何攻击的水印算法不多.文中利用Krawtchouk不变矩对平移、旋转和缩放的不变性以及Krawtchouk矩良好的局部特性和重构性能,根据水印的容量自适应地改变某些相对稳定的低阶矩来嵌入水印,并用Rijndael加密和Arnold置乱等技术以及构造的图像特征不变矩阵生成相关的二值逻辑表来进行版权认证.实验证明,该算法不仅对JPEG压缩、裁剪、噪声等常见攻击有较强的免疫力,而且对平移、旋转、缩放等几何攻击也具有较强的免疫力.

As a main method for copyright protection, the watermarking technique has been a hot topic for research. But there are few methods of practical robust digital watermarking, especially in the case of geometrically robust watermarking. Using translation, rota- tion, scaling invariant property, good local characteristics and excellent reconstruct ability of Krawtchouk moments, the robustness to the cropping of lower Krawtchouk moments are combined to obtain the watermarked image by modifying some selected moments ac- cording to the length of the watermark bits. With Rijndael encryption, Arnold transformation and the constructed invariant feature ma- trix, a related binary logical table is produced for copyright protection. The experimental results show that the embedded watermarking is effectively robust to the common attacks such as JPEG compression, cropping and added noise, as well as the geometric attacks such as translation, rotation and scaling.