摘要
数字图像可逆水印算法在水印嵌入容量和不可感知性方面要求越来越高。为了满足图像可逆水印算法的需求,提出一种基于三像素差值的多层可逆图像水印算法。该算法首先把原始图像按照三种类型进行水平分块,同时计算相邻三像素块的绝对差值,对差值进行分组,求出水平分块中的最大峰值点,将生成的二值水印嵌入在第一个像素和第三个像素的LSB中,同时记录最大峰值点所在块的索引和嵌入水印信息像素的最低有效位。其次,按照同样的方法对原始图像按照三种类型进行垂直分块,嵌入水印信息。实验仿真结果表明,该算法在不可见性、水印容量等方面较同类算法有显著提高。
The requirements of digital image embedding capacity and imperceptibility. In order reversible watermarking algorithms become exigent in watermark to meet the requirements, a muhilayer reversible image watermark algorithm based on three-pixel block differences is proposed. Firstly, the original image is divided into horizontal blocks according to three types. The absolute difference of adjacent three-pixel block is calculated simultaneously, then they should be grouped so that the maximum peak point of horizontal blocks can be obtained. The binary watermark is embedded in LSB of the first pixel and the third pixel. At the same time, the index of the block with the maximum peak point and LSB of embedding watermark is recorded. Then, the original image is divided into three types of vertical blocks, and watermark is embedded in the same way. Simulation result shows that the proposed algorithm has made a significant improvement in the aspects of invisibility and watermark capacity compared with other similar algorithms.
作者
钱华山
田丽华
李晨
Qian Huashan Tian Lihua Li Chen(School of Software Engineering,Xi＇ an Jiaotong University, Xi＇ an 710049, Shaanxi, China)
出处
《计算机应用与软件》
2017年第3期252-259,299,共9页
Computer Applications and Software
基金
国家自然科学基金项目(61403302)
西安交通大学科研业务基金项目(XJJ2016029)
关键词
图像水印
可逆水印
像素块
绝对差值
LSB
Image watermark Reversible watermark Pixel block Absolute difference LSB
