基于纹理方向性的非下采样剪切波水印算法

Non-subsample Shearlet Wave Watermarking Algorithm Based on Texture Directionality

为解决水印算法中不可见性与鲁棒性不可兼顾最优的问题,提出一种新的非下采样剪切波数字水印算法。对图像使用剪切波变换,变换后选取最强纹理方向性的子带作为水印的嵌入位置,利用奇异值分解实现水印的嵌入。实验结果表明,该算法结构相似性达到0.99以上,含水印图像在经过不同形式的攻击后,水印能够较好地被提取出来,且归一化相关系数平均值达到0.98,具有较好的鲁棒性。

In order to solve the problem of the irreconcilability between invisibility and robustness of watermarking algorithm,a novel watermarking algorithm using Non-subsample Shearlet Wave Transform （NSST） is proposed. The algorithm uses shearlet wave transform to images. The subband with strongest texture directionality after NSST is selected to carry watermark based on Singular Value Decomposition （SVD）. Experimental results show that the Structural Similarity Index Measurement（SSIM） is above 0.99. The watermark can be extracted and the Normalized Correlation （NC） reaches 0.98 on average after a series of attacks,which shows that the performance is greatly improved.