【摘要】 在充分考虑人眼视觉系统的基础上,提出一种基于小波变换的水印嵌入算法,首先在嵌入水印时,将宿主图像作适当层次的二维小波分解,分解出高频边缘等细节信息,然后对以低频信息为主的小波逼近子图再作二维DCT,将水印信息嵌入到DCT的低频和中频系数中。考虑到灰度水印嵌入的水印信息量大,除了在小波逼近子图嵌入数据外,通过合理设计强度因子,在高频带也嵌入部分数据。在基本不影响水印透明性的情况下最大化嵌入水印的强度和信息量。实验结果表明,应用本算法对常见的图像处理和噪声干扰具有很好的鲁棒性。更多还原

【Abstract】 By taking the human visual system into account,the paper proposes a new algorithm of digital image watermarking based on discrete wavelet transform.First,it proposes the dimension-wavelet decomposition of the host image embedded in watermark,and decomposes the detailed information of the high frequencies.Secondly,Discrete Cosine Transform(DCT) of the wavelet approximate sub-images which are mainly low frequency information is made,and consequently the watermark is embedded in low frequency and middle frequency coefficient of DCT.Considering the large amount information of watermark embedded,a part of data is embedded via designing reasonable intensity factor in high frequency area.The experiment results show that this algorithm is robust for image processing.更多还原