基于Curvelet变换的数字水印算法

A Digital Watermarking Algorithm Based on Curvelet Transform

数字水印技术能起到版权保护的作用,从数字水印的鲁棒性与不可感知性要求出发,介绍了Curvelet变换的多方向、多分辨、带通特点及各层的系数特征,提出了一种基于Curvelet变换和HVS的图像数字水印技术,这种数字水印方法是将数字水印嵌入到原始图像经Curvelet变换后的高频系数构成的矩阵当中.仿真实验表明该算法简单有效,原图像与嵌入水印后图像差异小,水印提取准确,不仅能保证数字水印不可感知性,而且在对嵌入水印图像进行裁剪、加噪、旋转及涂改等攻击后具有较强的鲁棒性.

Digital watermarking technology is a very good method for protecting copyright. In this paper, in terms of requisition of imperceptibility and robustness of watermarking, the multidirectional, multiscale and band-pass coefficient features of Curvelet transform axe introduced and a new image watermarking scheme based Curvelet and Human Visual System is proposed. Digital watermark are embedded in the high-frequency Curvelet coefficients. Experimental results that the proposed watermarking schente is feasible and simple, and the embedded watermarking images have litter difference with the original images and the extracted watermark is accurate. Moreover, it is imperceptible and robust against various signals processing such as cropping, noise adding, rotating and altering, etc.