基于FFST和Hessenberg分解的立体图像零水印算法

目的 为提高立体图像零水印方案抗几何攻击性能，提出一种基于快速有限剪切波变换（FFST）和Hessenberg分解的立体图像零水印算法。方法 首先分别对原始立体图像在YCbCr颜色空间下的左右视点亮度分量进行FFST，然后在得到的2个低频子带中，基于随机子块选择策略和Hessenberg联合分解来构造鲁棒特征矩阵，最后与预处理后的二值水印执行异或运算生成认证零水印。此外，零水印检测前先采用傅里叶-梅林变换方法对待认证的立体图像进行几何校正。结果 与相关算法相比，文中算法对常见非几何和几何攻击提取水印的平均NC值为0.984 1，表现出更优的抗攻击性能。结论 所提算法具有无损性和较强的安全性，可为立体图像版权保护提供可行的解决方案。

Stereo Image Zero Watermarking Algorithm Based on FFST and Hessenberg Decomposition

To improve the capability of stereo image zero watermarking scheme anti-geometric attacks, this work a stereo image zero watermarking algorithm based on Fast Finite Shearlet Transform (FFST) and Hessenberg decomposition is proposed. Firstly, the FFST is applied to the luminance components on the left and right viewpoint respectively of the original stereo image in the YCbCr color space to obtain the two low-frequency subbands. Then the robust feature matrix is constructed based on the random sub-block selecting strategy and Hessenberg joint decomposition from the above subbands. Finally, the certified zero watermark is produced by executing exclusive OR on the robust matrix and the preprocessed binary watermark. Furthermore, the Fourier-Mellin Transform is used to correct the stereo image to be certified before zero watermarking detection. Compared with related algorithms, the algorithm in this paper has an average NC value of 0.984 1 for common non-geometric and geometric attacks, showing better anti-attack capability. The proposed algorithm has lossless and strong security, and can provide a feasible solution for stereo image copyright protection.