摘要
混沌系统具有初值敏感性、参数敏感性和类随机性等特性。小波变换具有时频局部化特性,这一特性与人眼视觉系统的变换机制相符合。利用这些特点,首先利用经典的Logistic方程产生的混沌序列生成匹配模板对水印图像像素点置乱实现混沌置乱加密并按照16×16大小进行分块;然后针对人眼视觉系统的特点,对原始图像三级离散小波变换后的第二三级水平和垂直区域分块(16×16)并统计每块小波系数能量,根据每块能量从大到小的顺序分别嵌入每一块水印。实验证明,该方法具有一定的鲁棒性和抗破译性。
Chaotic system has such attributes as initial value sensitivity, sensitivity of the parameters and random- like. The Discrete Wavelet Transform （DWT） has a localized characteristic in time - frequency domain and a transform mechanism that accords with human visual systero. Fistly, the image watermark is encrypted and scrambled by the typical Logistic equation and splitted into blocks （1 6 × 16）. Secondly, the wavelet transform parameter can be splitted into blocks（ 16 × 16） according to energy of the wavelet transform parameter of horizontal and vertical blocks of the second and the third level. At last, by the order of the size of energy, the watermarking is embedded. The algorithm is robust and its resistance to the attack of cryptic analysis is better.
出处
《现代电子技术》
2009年第11期80-82,89,共4页
Modern Electronics Technique
