一种抵抗强剪切攻击的鲁棒性数字水印算法

Strong anti-robust watermarking algorithm

为了增强水印的抗几何攻击能力,提出了一种能够抵抗强剪切攻击的鲁棒性水印算法,即把水印嵌入在代表宿主载体基本特征的基矩阵中.理论分析表明:这种算法可以获得智能特征以抵抗强剪切攻击;可对水印进行加密扩频调制以增强隐蔽性;通过比较合成图像与原始图像的峰值信噪比,可自适应调整水印嵌入强度;引入改进的PCA(Principal Component Analysis)方法,加强了矩阵元素之间的联系,提高了算法的效率.实验表明,当图像剪切程度达到87.50%时,水印检测正确率为100%,同时算法对有损压缩、滤波、噪声等常规攻击同样具有良好的鲁棒性;算法嵌入容量大,宿主载体可为图像、音频等多种形式,是一个具有普适性的盲水印方案.

A digital watermarking algorithm that can resist the strong shear attack is proposed. The embedded strategies include： the watermark is embedded into the basis matrix on behalf of the basic characteristics of the host carrier for the first time, and the theoretical analytical result shows that the algorithm may obtain intelligence and resist shear; the watermark is encrypted spread spectrum modulation to enhance the hidden features; the watermark embedding intensity is adaptively adjusted by a comparison in the PSNR （Power Signal- to-Noise Ratio） between the original image and the synthetie image; the improved PCA（Principal Component Analysis） method is introduced, which strengthens the link between the matrix elements, to improve the algorithm＇s convergence speed. Experimental results show that the algorithm is robust to compression, filtering, noise as well as strong shear attacks, and confirm the validity of the theoretical result. The algorithm＇s embedding capacity is large and host vector may be an image, audio or others. The algorithm is of general applicability and is a blind watermark schem.