基于改进离散小波变化的数字水印技术  

Digital watermarking technology based on improved discrete wavelet transform

作　　者：彭荣杰 黎龙珍 PENG Rongjie;LI Longzhen(Department of Big Data and E-commerce,Qiannan Ethnic Vocational and Technical College,Duyun Guizhou 558000,China)

机构地区：[1]黔南民族职业技术学院大数据与电子商务系,贵州都匀558000

出　　处：《智能计算机与应用》2023年第7期15-18,26,共5页Intelligent Computer and Applications

基　　金：黔南民族职业技术学院院级科研项目(qnzyky-2022-05)。

摘　　要：离散小波变换的数字水印算法单一,且在鲁棒性、不可见性和安全性上较差,针对这一问题,本文在原有离散小波变化的基础上提出离散小波变换和分数阶傅里叶变换(DWT-FRFT)的数字水印算法。首先对载体图像进行离散小波变化,提取第三层小波系数,再结合分数阶傅里叶变换取其幅度系数进行水印信息嵌入,与其相位系数进行重组。该方法利用小波变换的多分辨率和分数阶傅里叶变换的频域特性,能更好地把水印信息嵌入在载体图像中。通过Matlab 2018a实验,证明该算法相对于传统离散小波变化,峰值信噪比(PSNR)和相关系数(NC)均是最优,可以有效地保证水印的鲁棒性、不可见性和安全性。为进一步提高数字水印版权保护技术提供了参考。The digital watermarking algorithm of discrete wavelet transform is single and has poor robustness,invisibility and security.To address this issue,this paper proposes a digital watermarking algorithm based on the original discrete wavelet transform and fractional Fourier transform(DWT-FRFT).Firstly,discrete wavelet transform is applied to the carrier image to extract the third layer wavelet coefficients.Then,the amplitude coefficients are combined with fractional Fourier transform to embed watermark information,and their phase coefficients are recombined.This method utilizes the multi resolution of wavelet transform and the frequency domain characteristics of fractional Fourier transform to better embed watermark information in carrier images.Through Matlab 2018a experiments,it is demonstrated that this algorithm has the best peak signal-to-noise ratio(PSNR)and correlation coefficient(NC)compared to traditional discrete wavelet changes,effectively ensuring the robustness,invisibility and security of the watermark.This research could provide the reference for further improving the copyright protection technology of digital watermarks.

关 键 词：数字水印 离散小波变换 分数阶傅里叶变换 ARNOLD变换 

分 类 号：TP301[自动化与计算机技术—计算机系统结构]