基于Tetrolet变换和SVD的QR码数字水印

Digital Watermarking Technology for QR Code Based on Tetrolet Transform and SVD

针对QR码数字水印的鲁棒性和不可感知性的平衡问题,提出一种基于Tetrolet变换和奇异值分解(SVD)的数字水印技术。首先,利用Tetrolet变换将QR码图像的能量信息集中于Tetrolet系数中,再对该系数进行SVD分解,最后将置乱加密的水印图像嵌入奇异值矩阵中,完成水印的嵌入。仿真实验结果表明,该方法可以有效抵抗高斯、椒盐、乘积等多种噪声攻击和旋转、剪切、平移等几何攻击。该算法能在图像不失真的前提下,有效提高水印的抗噪声和抗几何攻击的能力,实现数字水印系统不可感知性和鲁棒性的平衡,具有较强的实用性。

According to the balancing problem of the robustness and invisibility, a new digital watermarking technology for quick response （QR） code based on Tetrolet transform and singular value decomposition （SVD） is proposed. At first, the energy information of the QR code image is concentrated in Tetrolet coefficient using Tetrolet transform. And then, the coefficient is decomposed by SVD. At end, the watermarking embedding is completed by embedding the scrambling eneryption watermarking image to the singular value matrix. The simulation results show that this algorithm can effectively resist noise attacks of Gauss, salt and pepper and muhiplicative. It also can resist geometric attacks of rotation, shear and translation. This algorithm can effectively improve the ability to resist noise and geometric attacks, achieve the balance between the robustness and invisibility of the digital watermarking system in the prerequisite with the image without distortion. It shows a high practicability.