基于Arnold变换和DCT变换的数字水印算法

Digital Watermarking Algorithm Based on Arnold and DCT Transform

数字水印技术是解决多媒体数据版权保护问题的有效手段之一。提出了一种基于Arnold变换和DCT变换的数字水印算法。该算法首先使用Arnold变换对水印图像进行置乱处理,然后对原始载体图像进行8×8的DCT变换。为了提高水印鲁棒性,本算法采用多重嵌入的方法,在各个彩色分量相同位置像素块的DC系数上嵌入同一经过Arnold变换处理过的鲁棒水印。实验结果表明,该算法具有良好的抗攻击性和不可见性,是一种有效的方法。

Digital watermarking is one of the effective methods which can protect the copyright of multimedia data. This thesis presents a digital watermarking Algorithm based on Arnold and DCT Transform. Firstly, Arnold transform is used to shuffle the watermark image, then the algorithm makes 8~8 DCT on the carrier image. In order to improve the robustness of watermark, this thesis adopted the multi-embedded strategy. The DC coefficients in the block of the same location of each color components are embedded the same robust watermark which is transformed by Arnold. Experiments show that the improved algorithm is an effective approach which can resist the attacks and has good invisibility.