基于变换域的数字图像水印算法研究与实现

发布时间：2018-05-18 03:31

本文选题：数字图像水印 + 离散余弦变换　；参考：《苏州大学》2013年硕士论文

【摘要】：互联网的发展给人们获取数字作品越来越方便，但是数字产品的版权问题也日益突出，迫切需要一种新技术对数字产品信息的版权、完整性和真实性进行保护。数字水印技术通过将一些有特殊意义的信息嵌入到数字产品中，通过对嵌入信息的提取与检测分析，用以证明原创作者的版权所有权，有效解决了数字产品的知识产权保护问题。本文在分析和研究国内外数字水印技术现状并借鉴了前人研究成果的基础上，重点研究了基于变换域的数字图像水印技术算法，设计了基于变换域的两种数字图像水印算法，并分别进行仿真实验测试以验证算法的有效性和可行性。 1、提出了一种简单的基于离散余弦变换的数字图像水印算法。该算法首先将整幅图像分成块，对每一块分别进行DCT计算，在每一块中选取合适频段的系数，将水印信息分散嵌入到每一块所选取的DCT系数中，本算法简单且易于实现。实验结果表明该算法的水印不可见性较好。针对一般的攻击，水印具有较好的鲁棒性，但是针对大幅度的剪切攻击，提取水印效果较差。 2、提出了一种基于奇异值分解和离散余弦变换的数字图像水印算法。该算法对分块DCT变换的系数矩阵进行SVD变换，奇异值分解的稳定性、隐藏性和降秩的特性有利于增强嵌入水印的不可见性和鲁棒性，MATLAB仿真结果表明，算法具有较好的不可见性和抗JPEG压缩、高斯通滤波和旋转等能力，，同时对大幅度剪切攻击也具有较好的鲁棒性。
[Abstract]:With the development of Internet, it is more and more convenient for people to obtain digital works, but the copyright problem of digital products is becoming more and more serious. Therefore, a new technology is urgently needed to protect the copyright, integrity and authenticity of digital product information. Digital watermarking technology by embedding some special information into digital products, through the extraction of embedded information and detection and analysis, to prove the copyright ownership of the original creator. Effectively solve the problem of intellectual property protection of digital products. On the basis of analyzing and studying the current situation of digital watermarking technology at home and abroad and referring to the previous research results, this paper focuses on the digital image watermarking algorithm based on transform domain, and designs two digital image watermarking algorithms based on transform domain. Simulation experiments were carried out to verify the validity and feasibility of the algorithm. 1. A simple digital image watermarking algorithm based on discrete cosine transform is proposed. The algorithm first divides the whole image into blocks, calculates each block separately by DCT, selects the appropriate frequency band coefficients in each block, and distributes the watermark information into the selected DCT coefficients of each block. The algorithm is simple and easy to implement. Experimental results show that the watermark is invisible. For general attacks, the watermark has good robustness, but for the large clipping attack, the watermark extraction effect is poor. 2. A digital image watermarking algorithm based on singular value decomposition and discrete cosine transform is proposed. The algorithm performs SVD transform on the coefficient matrix of block DCT transform. The stability of singular value decomposition, concealment and rank reduction are helpful to enhance the invisibility and robustness of embedded watermark. The algorithm has better invisibility and anti-JPEG compression, high stone filtering and rotation capabilities, and is also robust to large shear attacks.
【学位授予单位】：苏州大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TP309.7

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