基于Asmuth-Bloom门限方案的小波域数字水印技术

摘要

为了进一步提高水印系统的安全性,文章在小波域数字水印技术研究的基础上,引入密码学中秘密共享的思想,提出了一种在小波变换域中基于Asmuth-Bloom秘密共享门限方案实现的数字图像水印分存算法。算法首先将水印信息分成若干份,然后分别嵌入到图像小波分解后的不同子图里,水印嵌入的强度不超过小波变换域的临界可见误差(Just Noticeable Difference,JND)门限。提取时,只需要部分内容就可恢复原始水印。实验结果表明,该算法不但隐蔽性好,而且对图像剪切、压缩等多种攻击具有很好的稳健性。%　　In order to improve the security of digital watermarking system, the paper introduces an idea of the secret sharing in cryptography to the digital watermark, and proposes a new image watermarking sharing algorithm based on Asmuth-Bloom in wavelet domain. First, the watermarking information is divided into several parts;then, the each part is embedded in the different frequency bands coefficients of the image wavelet decomposition respectively. Watermark embedding strength don’t exceeds just noticeable difference (JND) threshold in wavelet transform domain. This algorithm only needs a part of shares in the recover process. Experimental results show that this algorithm has not only a good hiding effect but also a good robustness against various attacks such as image cropping, JPEG2000 compression, etc.