应用水印旋转角度加密的双水印算法

提出一种基于水印旋转角度加密的新型双水印算法.该算法首先分块载体图像,选取预定大小的载体图像子图像作为嵌入可见水印的载体.其次,使用图像旋转算法对待嵌入的可见水印进行微角度旋转处理,用该旋转角度作为其中一个密钥,以此作为验证该可见水印是否为水印信息的手段之一.最后,在除了用于嵌入可见水印的载体图像的其他子块中使用模糊归类的方法,嵌入不可见的鲁棒水印.实验结果证明:该算法嵌入双水印后图像没有明显的降质,合法去除可见水印之后,载体图像也不会出现明显的降质;被恶意篡改之后的可见水印恢复能力强,而鲁棒性水印抵抗JPEG压缩、剪切、高斯噪声、滤波、缩放等常见的信号处理攻击和几何攻击性能良好.

A Dual Watermark Algorithm Using the Encryption of Watermark Rotation Angle

A new dual watermarking algorithm based on dual the encryption of watermark rotation angle is proposed. First, the algorithm blocks the original carrier image, and uses a sub-image of the original carrier image to embed the visible watermark. The size of the sub-image is predetermined by the visible watermark. Second, we process the visible watermark with the image rotation algorithm, so the rotation angle is used as one of the keys and use it as one of the means to test and verify the watermark information. Finally, the invisible robust watermark is embedded at the remainder original carrier image based on fuzzy classified. The experimental results show the presented algorithm can embed dual watermark image without significant degradation, and the carrier image doesn’t appear significant degradation when the visible watermark is removed legally. The visible watermark has a strong recovery performance after tampered, and the robust watermark has a good robustness against common signal processing and geometric attacks such as JPEG compression, cropping, Gaussian noise, filtering, scaling.