基于超混沌和离散小波变换(DWT)理论,结合Arnold置乱方法,提出了新型的数字图像水印算法,利用Arnold方法减弱水印图像像素之间的相关性,并采取Haken系统生成超混沌密钥序列,进行二次加密,大大增强了水印的安全性.同时,根据人类视觉系统(HVS)的特点,对原始图像进行分块处理,将加密后的水印分别以不同的强度嵌入并提取,给出了改进的嵌入提取方案.通过利用噪声、滤波、裁剪等方法对算法进行攻击测试,结果证明,此方案提高了水印图像的不可见性和鲁棒性,具有极强的抗攻击性.
Based on the hyperchaos and Discrete Wavelet Transform (DWT) algorithm, combined with the Arnold scrambling method, a novel digital image watermarking algorithm was presented. The method makes use of Arnold method to weaken the correlation among the pixels of the watermark and adopts Haken system to generate the hyperchaotic key sequence to undertake the second encryption, strengthening the security of the watermarking. At the same time, according to the characteristics of human vision system (HVS), the original image is split into blocks, and the encrypted watermarking is embedded and extracted with different strength. The improved embedding and extraction scheme were proposed. By using methods such as the noise, filtering and cutting to at'tack the algorithm, the experiment results show that the scheme improves the invisibility and robustness, and possesses strong anti - attacking ability. h