复合式的多功能数字水印算法

提出了一种鲁棒性数字水印和脆弱性数字水印相结合的复合式水印算法,具有较好的双重保护性能,即鲁棒性数字水印用于版权认证方面和脆弱性数字水印用于图像内容的保护.首先,在原始载体图像的DCT中频域上嵌入不可见水印;其次,再根据LSB算法在空域自适应地嵌入脆弱性数字水印.实验结果表明,该方法不可见性好,对一般的图像处理和攻击,如JPEG压缩、滤波、加噪声、旋转、缩放等都有良好的鲁棒性,同时还能对图像中细微的篡改进行有效精确的定位,并且作为一种盲水印算法有着良好的安全性.

Compound multipurpose digital watermarking algorithm

A compound watermarking algorithm combined the robust watermark with the fragile watermark is proposed, with better dual protection capability, viz. copyright authentication by robust watermark and content protection by fragile watermark. Firstly, the robust watermark is embeded in the intermediate frequency of DCT of the original image. Next, the fragile watermark is adaptively embedded into spatial domain based on LSB. Experimental results show that the method has good invisibility, and is robust against normal image processing and kinds of attacks, for example JPEG compression, filtering, adding noise, rotating, zooming. And can detect the location of any minute changes in images. At last, being a blind watermarking algorithm has good security.