一种基于DWT的R-F数字水印技术

R-F Digital Watermarking Technique Based on DWT

文章提出一种R-F(Robust-Fragile)数字水印新算法。该算法利用小波多尺度方法提取图像的边缘特征,将其作为数字水印自适应地嵌入到原始图像的小波域中。边缘水印与图像内容相关,因此,可将其看作图像的数字指纹。在水印提取阶段,利用相关运算可以检测水印的存在性,而利用比较运算可以判断出原始图像被篡改的部位。因此该算法具有鲁棒性和脆弱性水印的双重特点。实验验证了算法的有效性。

A new R-F digital watermarking algorithm is proposed in this paper.Instead of using the random number or the logos as watermarks,the image edge features which are extracted from the original image by using DWT (Discrete Wavelet Transform)edge detection method has been used as the watermark.This kind of watermark can be treated as a digital finger mark of the image for it is generated from the image content.Then it is self-adaptively embedded into the DWT domain of the original image.During the watermarking extraction,using the correlation operation the watermark ex-istence can be testified,and using the compare operation the alteration region can be localized.Thus the scheme not on-ly apply to check the original ownership of an image but also apply to verify its integrity.