【作者】 刘华民；

【导师】 徐向阳； 张先军；

【作者基本信息】 湖南大学 ， 计算机应用技术， 2008， 硕士

【摘要】 随着数字产品的普及,围绕数字产品的版权保护和安全问题,提出了一种新的数字产品版权保护新技术-数字水印(Digital Watermark)技术。本文对基于DWT和HVS的双彩色图像水印嵌入算法和基于数字水印技术的数字版权系统进行了一定的研究。首先,作为技术的研究基础,本文搜集了大量与数字水印技术相关的文献资料,从中系统分析归纳出数字水印技术的发展渊源、系统模型、评价指标、分类、攻击方法与对策、嵌入容量以及水印检测方法等多方面的信息。并简单介绍了数字水印研究的相关理论知识,如公钥加密理论、图像置乱加密技术、哈达玛变换、HVS人眼视觉模型等知识。在掌握数字水印技术系统特点的前提下,分析和总结了传统的水印算法和思路,为下一步进行具体算法设计做好准备。其次,根据变换域的水印算法设计思路,从扩频技术理论角度,提出了基于离散小波变换(DWT)和人类视觉系统(HVS:Human Visual System)特性的彩色图像的双彩色水印算法。根据原始彩色图像的小波系数高、低频分布的特点,统计原始彩色图像的小波分块的能量和纹理大小,利用人类视觉系统的特性设置嵌入系数,将混合后的彩色水印的R、G、B分量分别嵌入到彩色图像的R、G、B分量中。接着,结合版权认证的需要提出了一种结合了可见和不可见双数字水印算法,数字产品最终用户能够通过获取版权所有者提供的去除密钥,实现数字图像的盲提取恢复,同时著作权所有者能够根据自己的私钥从数字产品中提取私有水印证明自己的著作权,初步实现了数字图像的版权保护和交易。并基于上述的水印算法,提出了一种简单的数字水印版权交易系统模型。最后,总结了本人的研究结果并对数字水印的进一步发展进行了展望。更多还原

【Abstract】 Along with the popularization of digital product, about the problem of digital product copyright protection and the security, a new technical of digital product copyright protection is proposed-Digital Watermark.The article has conducted certain research about double color image watermark inserting algorithm based on DWT and the HVS and digital copyright system based on the digital watermark technology.At first, as the research foundation, the article has collected massive materials about the digital watermark technology, from the materials, the article analyses the development origin of digital watermark technology. system model, evaluation index, classification, the attach methods and the countermeasures, the inserting capacity and the watermark examination method and so on. And introduced simply the theories about digital watermark research, like the public key encryption theory, the image encrypt randomly of technical, Hadamard transform, knowledge of HVS and so on. On grasping digital watermark system technical characteristic premise, analyzed and summarized the traditional watermark algorithm and the mentality, prepared for the next step to design concrete algorithm.Second, according to the watermark algorithm design mentality of transformation territory, from the angle of spread spectrum technology theory, proposed a color image double colored watermark algorithm based on DWT and HVS. According to wavelet coefficient high and low frequency distribution characteristic of primitive color image, statistics primitive color image wavelet piece energy and texture size, using the characteristic of human vision system to set inserting coefficient, inserts the mixed R, G and B component of colored watermark separately to R, G and B component of color image.Third, for the copyright authentication, proposed a double digital watermark algorithm which unified obviously and unobvious methods, through getting the elimination key of copyright owner, the digital product end-user can realization digital image blind extraction restore , simultaneously the copyright owner could prove own copyright according to the private watermark withdraw from the digital product using his own private key, the article have initially realized the digital image copyright protection and transaction. And based on the above watermark algorithm proposed a simple digital watermark copyright transaction system model. Finally, summarized myself findings and forecasted the further development of digital watermark.更多还原