【作者】 伯梅；

【导师】 高隽；

【作者基本信息】 合肥工业大学 ， 信号与信息处理， 2007， 硕士

【摘要】 数字化信息时代的到来，使多媒体信息的传递、流通变得很便捷，但是随之而来的侵权盗版行为也日益猖獗。数字水印技术通过在数字作品中加入不易察觉但可以判定区分的秘密信息以达到保护版权的目的，成为解决多媒体信息安全问题的有效补充方法。因此研究并发展数字水印技术具有重要的现实意义和商业价值。对于用于所有权保护的数字图像水印技术，最重要的两个特性是不可见性和鲁棒性，而这两个特性是相互制约的关系，因此研究一个能有效兼顾这两个特性的水印算法是有意义的。对于很多实际应用，需要允许公众用检测密钥检测水印，进而表明版权所有。但是对于对称水印系统，公开了检测密钥就相当于公开了嵌入密钥，因此大大增加了水印被破坏的成功率。可见，研究嵌入密钥和检测公钥不同的非对称水印算法是有意义的。本文的主要研究内容如下：(1)总结了近年来国内外在数字水印领域的研究成果和进展，对数字水印的多种算法进行了较为系统的研究；(2)针对不可见性和鲁棒性相互制约的关系，设计了一种不可见鲁棒水印算法。实验结果验证，该算法具有良好的不可见性和鲁棒性；(3)针对对称水印技术在实际应用中的缺陷，设计了一种非对称水印算法。通过理论分析和实验验证，该算法可以实现良好的非对称性、不可见性、鲁棒性和安全性。更多还原

【Abstract】 Because of the coming of digital information age, the spread and currency of the multimedia information become conveniently. Simultaneously, piratical behavior becomes more rampant. Digital watermarking technology embeds secret information which can be determined and can’t be seen into the digital production in order to protect the copyright. Therefore, Digital watermarking technology becomes an efficient complementary method for multimedia information security. The research of digital watermarking technology makes important practical meaning and commercial value.Digital image watermarking technology for copyright protection has two important specialities: invisibility and robustness. The specialities are incompatible. So, the research of an efficient watermarking algorithm which can gives attention to two characteristics is significative. In a great many applications, people should be permitted to detect watermarking by detecting secret key. But in symmetric watermarking system, if the detecting secret key be published, the embedding secret key can be known. It induces that the probability of watermarking being destructed increases greatly. So, the research of asymmetric watermarking algorithm is significative, in which the secret key of detection and embedment are different.Our work in this dissertation is mainly about:(1) The dissertation sums up the research in the domestic and abroad field of digital watermarking technology and gives a systematic research on the various watermarking algorithms.(2) Contraposing the restricting relation of invisibility and robustness, an invisible robust watermarking algorithm is proposed. It’s experimentally proved that the invisibility and robustness of our algorithm are well.(3) Contraposing the disfigurement of symmetric watermarking technology in some practical applications, an asymmetric watermarking algorithm is proposed. It’s theoretically and experimentally proved that the asymmetry, invisibility, robustness and security of our algorithm are well.更多还原