摘要
提出了一个针对图象水印的DCT域的水印算法,该算法基于利用人眼视觉掩蔽特性(HVS)的块分类方法,对原有的此类方法进行了改进,更大挖掘了载体图象的信息隐藏能力。在图象水印的嵌入方法上,采取了将水印图象进行DCT变换从而可以利用各块比例系数的差异嵌入不同频率的DCT系数。同时,对各块的DCT系数进行调整,使得各频率的能量基本相当,间接地提高了信噪比。经过以上几个方面的改进,得到的水印具有很好的清晰度。
In this paper,we propose a DCT domain watermarking aimed at image watermark.This algorithm is based on the improved block Classification that enhances the information hiding ability of cover image.In the watermark embedding process,we transform the watermark image into DCT domain,so that we can utilize the different embedding coefficients of each block.On the other hand,we adjust the DCT coefficients of each block to make them in the same level.This enhances the SNR of watermark.Through the improvements mentioned above,we make the image watermark more clarity.
出处
《计算机工程与应用》
CSCD
北大核心
2004年第30期76-78,115,共4页
Computer Engineering and Applications
关键词
DCT
图像水印
块分类
降噪
DCT,image watermarking,block classification,noise reduction