基于Arnold置换的交换加密水印算法

针对载体图像内容安全与数字水印版权保护,结合Arnold置换与直方图平移可逆水印算法,提出基于Arnold置换的交换加密水印算法.算法利用置换后图像直方图不变的特性,将在密文中嵌入水印的操作映射到明文中,实现了加密与水印操作先后顺序的交换.在提取水印时,可直接从含水印的密文中提取水印,也可解密后再提取水印.实验结果表明,该算法加密操作与水印嵌入操作间的先后顺序不影响含水印密文的生成,解密操作与水印提取操作的先后顺序不影响水印提取与图像恢复,且直接解密得到的含水印明文图像质量较高,水印的不可见性好,算法有较高的效率.

Commutative Encryption and Watermarking Algorithm Based on Arnold Permutation

To protect the security of carrier image content and digital watermark copyright, this study proposes a commutative encryption and watermarking algorithm integrating the Arnold permutation and histogram translation-based reversible watermarking algorithm. Taking advantage of the invariance of the image histogram after Arnold permutation, the algorithm maps the operation of watermark embedding in ciphertext to plaintext, which realizes the exchange of encryption and watermark embedding in operation sequence. The watermark can be extracted directly from the watermarked ciphertext, or be extracted after decryption. Experimental results show that the sequence of encryption and watermark embedding of this algorithm does not affect the generation of watermarked ciphertext, and the sequence of decryption and watermark extraction does not influence watermark extraction and image restoration. In addition, the direct decryption yields high-quality watermarked plaintext images, good invisibility of the watermark, and high efficiency of the algorithm.