【作者】 杨树国；

【导师】 孙尧；

【作者基本信息】 哈尔滨工程大学 ， 导航、制导与控制， 2003， 博士

【摘要】 近年来，多媒体存储与传输技术的不断进步，尤其是Internet技术的盛行，带动了数字媒体应用的迅猛发展，各种形式的多媒体作品包括图像、视频、音频等得以网络的途径向外发布，这些技术给人们带来了极大的方便，但随之而来的副作用也十分明显，例如任何人都可以通过网络轻而易举地得到他人的原始作品，尤其是数字化的图像、音乐、电影等，甚至有些人不经作者的同意而对原作品任意加以复制、修改，严重地侵害了作者的著作权，因此如何在网络中实施有效的版权保护和解决信息安全的问题，也就成为了一个迫在眉睫的研究课题。 在这种情况下，一种专门解决互联网上多媒体信息安全的技术——数字水印技术诞生了，它将水印嵌入到数字化媒体中，然后通过对它的检测(提取)来对图像的使用情况进行跟踪，从而实现隐藏传输、存储、版权保护等功能。目前数字水印已经成为多媒体版权认证和完整性保护的有效手段。 本文以静止图像为研究对象，首先对水印技术中亟待解决的问题进行了研究，接着将目前最流行的图像处理技术(如DCT、小波变换、分形技术)引入到数字水印技术中来，创造性地提出了基于分形变换的数字水印解决方案，最后又在零水印技术方面进行了探索，主要内容如下： 1．对人类视觉系统的特性进行了全面的分析和研究 人类视觉系统的特性是任何图像处理技术必须优先考虑的环节，数字水印技术也不例外，为了使人类视觉系统的特性和数字水印技术很好地结合，本文首先对人类视觉系统理论进行了全面细致的分析和研究，在详细阐述了人眼的生理结构及人眼对颜色的感知过程的基础上，建立了人眼的感知模型和人类视觉系统的JND模型，这些工作为后来水印信道容量的研究、水印嵌入强度的确定等工作奠定了基础。 2．全面系统地研究了水印信号的处理技术 数字水印技术除了水印嵌入和提取的算法外，还有许多工作需要做，如水印的选码、编码、调制、解调、能量的确定等等，这些预处理和后处理工作是算法有效实施的必要保证，正是基于这样的认识，本文利用较大的篇幅对水印的基本理论知识进行了详细的分析和研究，在水印的调制方面，提出了混沌调制法；在图像水印的置乱方面，提出了混沌置乱法；在文字水印的处理上，引入了BCH编码；在水印容量分析方面，结合现代通信理论，对图像在DCT域和小波域内的水印容量估算进行了详细的探讨，这些工作不仅为本文后期工作铺平了道路，而且对数字水印的研究具有重要的意义。 3.提出了基于分形理论的数字水印方法 将分形技术、DCT和DWT变换技术、水印技术有机地结合起来是本文的一大创新，分形技术在图像编码方面具有强大的生命力，DCT和DWT变换技术在图像处理方面有着广泛的应用，因此本文将分形变换技术引入到数字水印技术中来，分别在DCT域和小波域内提出了分形水印技术，并且通过大量的实验证实了分形水印技术的可行性，这无疑是一种新的思想和解决方案。 4.在小波域内提出了一种新的零水印技术及其解决方案 本文突破了传统的“向原始图像中嵌入水印”的常规解决方案，创造性提出了一种新的零水印技术，该方法从数字水印的根本目的出发，不通过向图像中嵌入任何数据而解决图像的版权认证问题，不但使图像无任何失真，而且水印的鲁棒性好，此外该方法还可实现数据隐藏功能，是一种非常新颖的、前景看好的数字水印技术。更多还原

【Abstract】 Recently, the development of multimedia storage and transmission technology,especially the popularization of the Internet technology push the development of the digital media application,Many types of multimedia works such as image,video and music can be conveyed in a new way of network.These technologies bring people many conveniences,but they also bring us some large side effects,for example,anybody can get the original products of others easily, especially digital products such as images,musics,films. Someone can copy and tamper the original works arbitrarily under disagree,as infringes the author’s copyright. How to protect the copyright effectively and solve the problem of information safeties on network is a urgent subject.Under this condition, as a kind of technology to solve multimedia information security problem on network, watermarking technology comes up into being.It embeds watermarks into the digital medias,then carries out the functions such as informations hiding,storing, copyright safeguarding by tracking the use of the image by detecting the watermarks.At present,watermark technology becomes a kind of effective means to multimedia copyright authentication and its integrity safeguarding.This paper takes still images as example,firstly researches the urgent problems of the watermark technology, it brings present popular image process technology into watermark technology in succession(such as DCT,DWT ,fractal technology).It firstly innovates a watermark scheme based on fractal transform,and studies the zero-watermark technology. The main contents are described as followed:1. makes general analysis and research on Human Visual SystemThe characteristicness of Human Visual System is the process being considered firstly for every image process technology,include watermark technology,In order to join the characteristicness of HVS and the watermark technology together,this paper analyses and researches the HVS theoretics particularly firstly.It build the aesthesia models and the JND models after discussing eyes’ biology configuration particularly and expatiating eyes’ aesthesia process.These works provide the foundation for the later research of watermarkchannel capacity and the watetmark embedding intensity.2. Researches the basis watermark managing works particularly and systemly. There are many works to do on watermak technology except watermarkembedding and extraction arithmetics such as the watermark choosing, encoding, modulating, demodulating and the watermark capacity.These prior and ultimate works ensure that the arithmetic is brought into effect.Just understanding these,this paper analyses and researches the basic watermark theoretics in many pages.It brings forward chaos modulation on watermark modulating, brings forward Chaos permuting on image permuting, introduces BCH encoding on letter watermark processing and discusses the approximate estimate of the watermark capacity in DCT domain and DWT domain by applying the current communication theoretics.There works not only extend ways for the later work but also are significative on watermark research.3. Brings forward a watermark method based on fractal theoreticsThis paper has a novelty that joins the fractal technology,DCT and DWT transform,watermark technology together.Fractal technology has strong vitality on the image encoding.DCT and DWT transforms have broad applications on the image process. So this paper introduces fractal technology into watermark technology, brings forward fractal watermark technology in DCT and DWT domain and tests the fractal watermark technology by many tests.Fractal technology is a new thought and solved scheme without doubt.4. Bring forward a now zero-watermark technology and scheme in the DWT domain.This paper changes the traditional and common scheme that embeds watermark into original image and brings forward a new zero-watermark technology.This method starts from the motive of watermark to solves the image authenticate problem without embedding any data into image.It not更多还原