摘要
提出了一种基于小波变换(DWT)和离散余弦变换(DCT)的图像扩频水印技术。该算法首先将原始图像进行DWT和DCT变换提取图像中重要的频率部分,将扩频后的水印图像嵌入到经变换后的原始图像中。然后利用扩频序列的自相关函数特征进行检测提取水印,将从受到攻击的图像中提取出的水印和原始水印的相似性进行计算得出实验结果,从而得出该算法嵌入的水印具有良好的不可见性,以及对JPEG压缩、几何剪切、噪声干扰等攻击具有较强的鲁棒性的结论。
In the algorithm ,it proposed image spread spectrum watermarking base on both DWT and DCT.Insert the watermarking that modulated by direct sequence spread spetrum into the DWT and DCT of the cover image.Then take the advantage of autocorrelation features with spread spectrum sequence to recovery the watermarking embedded,and calculate the similarity between original watermarking with recovery one.The experiment results demonstrate that the watermarking embeded is transparent enough and the algorithm proposed is robust enough to some image degradation process such as JPEG compression,cropping noise and other attacks.
出处
《电子测试》
2011年第5期61-63,共3页
Electronic Test