【摘要】 本文提出了一种基于混沌加密的小波域数字图像水印算法,首先通过对原始图像进行离散小波变换,提取其低频部分作为嵌入区域;然后再次利用小波变换对水印进行分解,得到水印的四幅小波分解子图,用混沌序列对4幅子图进行置乱,经小波逆变换完成水印加密;最后将加密后的水印嵌入到原始图像的低频部分中。在提取水印时,通过水印相似系数NC和峰值信噪比PSNR评价水印质量,实验结果表明,提出的算法可以抵抗JPEG压缩、噪声、滤波等几何攻击,图像加密效果好。更多还原

【Abstract】 In this paper,digital watermarking algorithm based on chaos encryption and wavelet domain is referred.During the embedding of the watermarking,discrete wavelet transform is done firstly and extract low frequency part as the embedding field;secondly,decompose the watermarking by wavelet transform and to get four sub-images,to scramble the four sub-images by chaos sequence,the encrypted watermarking is obtained by inverse wavelet transform of the scrambling coefficients;finally,embed the encrypted watermarking into the original image.The similar coefficient NC and peak noise to signal ration PNSR are used to evaluate the algorithm.The experiment results indicate that this algorithm can resist JPEG compression,noise attack,filter and so on.The effect of watermark image is very well.更多还原