提出一种在小波域嵌入双水印的新算法,该算法提取小波低频域的特征信息生成两个水印。将一个水印结合邻域信息以块量化方法嵌入,用于版权保护,将另一个水印的Hash值以单系数量化方法嵌入,用于内容认证,量化步长根据邻域的纹理特征自适应确定.实验结果表明,该算法在保护数字图像版权的同时,能够很好地完成内容真实性认证.
A bi-watermarking algorithm with adaptive quantization is proposed based on DWT and image contents. In this algorithm, two watermarks are generated by extracting image feature from low frequency components. One watermark, for copyright protection, is embedded by block quantization with neighbor information, and another, for content authentication, is embedded by singular coefficient quantization. The quantization level is adaptively decided by texture features. It is shown in Experiments that the proposed bi-watermarking algorithm is good at copyright protection and content authentication simultaneously.