【作者】 丁镠；

【导师】 程显毅；

【作者基本信息】 江苏大学 ， 模式识别与智能系统， 2010， 硕士

【摘要】 随着网络通信的普及,许多传统媒体内容都向数字化转变,随之而来的副作用是通过网络传输数字媒体内容使有恶意的个人或团体有可能在没有得到作品所有者的许可下拷贝和传播有版权的内容,因此如何在网络环境中实施版权保护和信息安全已成为一个迫在眉睫的现实问题。本文在对数字水印理论及技术进行深入探讨的基础上,做了以下一些研究,主要内容包括:(1)研究一种新的具有自适应功能的鲁棒数字水印算法。该算法利用JPEG量化矩阵来选择系数,增强水印的鲁棒性和抗干扰能力。较好的协调了水印特性中的隐蔽性和效果性对立矛盾问题,置乱加密技术的应用使得水印大安全性大大提高并且也降低了水印数据间的相关性。对该算法进行各种图像攻击的鲁棒性测试,试验结果表明比小波方法和常规DCT方法在鲁棒性和效果性方面有较大改进。(2)针对格式化中文文本中数字水印抗攻击性不强、鲁棒性较差、透明性不太好的问题,本论文充分考虑汉字自身的特点,研究了一种基于汉字结构知识的鲁棒性文本数字水印新算法,该研究对文本信息安全的发展和应用有着重要的意义,对解决目前互联网上比较脆弱的安全机制是一个有益的尝试。(3)针对网络博客的非法转载或者盗用,在基于自然语言处理技术的基础上,提出了二次水印算法。算法从技术上解决了博客文章的版权保护问题,能够较精确的进行侵权认证。融合了电子签名的加密技术同时还能保证完整性。更多还原

【Abstract】 With the popularity of network communication, many traditional media is digitizing. The following side effect of transmitting digital media on network is that malicious individuals or groups may copy or disseminate copyrighted work without its owners’ permission. So it has become an immediate practical problems that how to implement copyright protection and information security in network environment.On the basis of discussing digital watermarking theory and technology, the research work is as following:(1) A new adaptive digital robust watermarking algorithm is presented. The algorithm enhances the watermark robustness and anti-jamming capability by choosing DCT coefficients with JPEG matrix. It coordinates the contradiction of watermark’s concealment and effect. Scrambling encryption technology reduces the relativity among watermarking data but hugely increases the security of watermarking. When making attacks on various images to test the algorithm’s robustness, it shows that it has better robustness and effectiveness when compared to the wavelet algorithm and the conventional DCT algorithm.(2) When refer to the problems of weak anti-aggressive, poor robustness and transparency of digital watermarking in formatted Chinese text, after fully consideration of Chinese character’s features, this paper proposes a new robust text digital watermarking algorithm based on the structure knowledge of Chinese characters. The research is quite important to the development and application of text information safety. Furthermore, it is also a beneficial try to improve the comparatively weak security mechanism on the Internet at present.(3) To solve the problem of illegally copying, pirating and propagating on network blogs, a double watermark copyright protecting algorithm is proposed based on natural language processing. The algorithm technically solves the copyright protection problem on blogs and it can also decide copyright infringement quite precisely. It can not only combine electronic signatures encryption technology but also ensure its integrity.更多还原