基于QR分解的强鲁棒性双彩色盲水印算法

Robust dual color blind watermarking algorithm based on QR decomposition

提出了一种将彩色快速识别(QR)码作为水印嵌入彩色宿主图像的强鲁棒性盲水印算法。首先对彩色宿主图像分通道进行离散小波变换(DWT)和分块QR分解得到非重叠的酉矩阵,然后将QR码分通道置乱加密归一化后嵌入到宿主图像对应通道酉矩阵的系数差中。仿真实验结果表明,本算法在满足不可见性的同时具有较强的鲁棒性;相比现有算法,本算法不仅能够抵抗旋转和裁切攻击,在JPEG压缩和噪声滤波攻击方面的抵抗能力也有较大提升;而且本算法属于盲水印技术,具有较大的实际应用价值。

One blind watermarking algorithm with strong robustness by embedding c olor quick response （QR） code into color host image is proposed.The study found that there is a strong stable diff erence between the second row first column element and the third row first column in the unitar y matrix U after the image is processed by wavelet transform and 4×4non overlapping block QR de composition,even in the case of image attack.So we can embed watermark and extract watermark in the blind manner. First,the host image is represented by R,G,B component images,and the unitary matrix U of each component is obtained via discrete wavelet transform （DWT） and 4×4nonoverlapp ing block QR decomposition.Then each component of QR code is scrambled and normalized,and the watermark informat ion is embedded into the difference of coefficients in the unitary matrix of the host image.The simulation results show that this algorithm has strong robustness while meets the invisibility.Comp ared with the existing algorithms,this algorithm not only can resist rotation and crop ping attacks,but also can improve the ability to resist the JPEG compression and noise filtering attacks.And this algorithm is a blind watermarking technology,so it has great practical applicati on value.