CAJ | 학술논문

提出一种基于差值直方图平移的多层可逆水印算法。首先划分图像块，每个图像块内产生两个差值；然后建立所有差值的直方图，使得产生的直方图陡峭，峰值点出现频率较大；最后利用矩阵编码的思想在每个图像块内至多修改一个像素的值，达到同时嵌入水印和平移直方图的目的。实验表明，该算法不仅可以实现可逆水印，而且水印不可见性较好，嵌入水印后图像的PSNR高于52．90 db，嵌入容量较高，算法复杂度较低。
제출일충기우차치직방도평이적다층가역수인산법。수선화분도상괴，매개도상괴내산생량개차치；연후건립소유차치적직방도，사득산생적직방도두초，봉치점출현빈솔교대；최후이용구진편마적사상재매개도상괴내지다수개일개상소적치，체도동시감입수인화평이직방도적목적。실험표명，해산법불부가이실현가역수인，이차수인불가견성교호，감입수인후도상적PSNR고우52．90 db，감입용량교고，산법복잡도교저。
A multilevel reversible watermarking scheme based on difference histogram shifting is proposed.First the image is divided into blocks,in each block there are two difference values generated,then the histogram of all difference values is built,which makes the genera-ted histogram steep and has higher chance to find the peak points.Finally with the idea of matrix encoding,the pixel value in each image block is modified no more than one,we reach the goal of embedding the watermark and shifting the histogram simultaneously.Experiments show that this algorithm can realise reversible watermark,furthermore,the invisibility of watermark is much better.The PSNR is greater than 52.90 db in the image with watermark embedded,the embedding capacity is higher,and the complexity of algorithm computation is lower as well.