一种基于QR分解的脆弱水印算法

A Fragile Watermarking Algorithm Based on QR Decomposition

提出了一种基于QR分解的脆弱水印算法。该算法运用矩阵的QR分解技术,把原始图像信息转化为很短的二进制比特串,并把其作为水印嵌入到原始图像中随机选取的某些像素的LSB位。该算法不仅能检测到水印图像的任何改动,同时还保证了水印图像的质量。为了对水印图像的变化像素进行定位,提出了一种运用分块技术的扩展算法,并对此扩展算法进行改进,使其能够抵抗剪切-粘贴攻击。实验证明,该算法对水印图像的改变非常敏感,定位算法也有很好的效果。

A fragile watermarking algorithm based on QR decomposition scheme is presented in this paper. It is a technique that applying the idea of the QR decomposition to the fragile watermarking. It operates in this way; convert the original image into short binary bits and insert the binary bits into the LSBs of some randomly selected pixels of the original image. In this way, we can detect any modification of watermarked images while the quality of watermarked images still keeps high. To locate the changed position we propose a block-wise algorithm, and improve it to resist the cut-and-paste attack. Experimental results show that the algorithm is sensitive to the modification of watermarked images and location is also effective.