基于Slant变换的脆弱水印算法

Fragile Watermark Algorithm Based on Slant Transform

摘要: 针对图像内容的真伪和完整性难以鉴定的问题，本文提出一种基于Slant变换的脆弱水印图像认证的算法。该算法的思想是首先将原始图像进行8 × 8的分块，再对每一个分块进行Slant变换；然后利用Logistic混沌映射产生一个混沌序列，将该混沌序列与水印图像异或，得到水印信息；将水印信息嵌入到经Slant变换后的中频系数中，再进行Slant逆变换得到嵌入水印的图像。利用Slant变换，使得计算更加简单快速，增强了水印的不可见性。仿真结果表明，该算法具有良好的定位篡改能力。

Abstract: For the problems of image content’s authenticity and integrity are difficult to identify, this paper proposes a fragile watermark image authentication algorithm based on Slant transform. The algo-rithm’s idea was that the size of the original image is divided into 8 × 8 block, then each block do Slant Transform operation. Then using the Logistic chaotic generates a chaotic sequence, the chaotic sequence and the watermark image do xor arithmetic, and we get the watermark information. The watermark is embedded into the Slant middle frequency coefficients, and then we get the watermarked image by doing Slant inverse transformation. The Slant transform makes calculation more simple and fast, and enhances the invisibility of the watermark. The simulation results show that the algorithm has good capability of tampering localization.