多涡卷混沌系统在图像水印加密上的应用研究

Research on the application of multi-scroll chaotic system in image watermarking encryption

提出了一种基于多涡卷混沌系统对含有版权信息的原始水印图像进行双重加密的方法.首先将混沌系统与DNA编码及DNA计算相结合设计了一种包含置乱操作的原始水印图像加密方案,分析其加密直方图、相邻像素相关性等统计特性.在离散小波变换结合奇异值分解算法(DWT-SVD)的基础上,把加密后的水印图像嵌入到载体图像中.通过实现水印信息的加密、嵌入和提取,对含有水印的载体图像的攻击以及对攻击后的水印进行峰值信噪比和归一化相似度的评价,整体实现了基于DWT和混沌加密的数字水印系统.

Based on a multi-scroll chaotic system,a method of double encryption for original watermark image containing copyright information is proposed.Firstly,an original watermark image encryption scheme including scrambling operation is designed by combining chaotic system with DNA encoding and DNA calculation,and its statistical characteristics such as encryption histogram and correlation between adjacent pixels are analyzed.In the light of discrete wavelet transform combined with singular value decomposition(DWT-SVD),the encrypted watermark image is embedded into the carrier image.A digital watermarking system with DWT and chaos encryption is implemented by encrypting watermark information,embedding watermark and extracting watermark,attacking the carrier image containing watermark and evaluating the watermark by PSNR and NC.