【作者】 朱建红；

【导师】 范新南；

【作者基本信息】 河海大学 ， 通信与信息系统， 2004， 硕士

【摘要】 多媒体数据的数字化为多媒体信息的存取提供了极大的便利，极大地提高了信息表达的效率和准确性。各种数据可以自由地发布到网上，但是盗版问题也随之而来。传统的加密技术不能完全解决版权保护问题，只能在传输过程中对数据进行加密，不仅影响人们使用，而且安全性不高。数字水印技术是解决这一问题的有效途径，在多媒体版权保护方面具有加密技术所不具有的优点，并且与之有着很强的互补性。 本文对彩色图像的数字水印技术进行了研究。研究了彩色图像特点，根据DCT特点确定了水印嵌入区域，在原有的HVS图像块分类的基础上进行改进，完善了HVS图像块分类。提出了一种新数字水印算法，通过DCT变换来进行嵌入，利用HVS特性对图像进行分类，根据8×8图像块中RGB的比例来自适应地调整水印嵌入强度，在RGB颜色分量中嵌入水印。实验结果表明，本算法具有较好的鲁棒性和不可见性。 最后总结全文，并对未来数字水印的研究方向进行了展望。更多还原

【Abstract】 The digitalization of the multimedia data provides much convenience for the multimedia information’s storage and extraction.lt makes much improvement of the efficiency and veracity of information expression.Each data can be distributed freely in Internet,but pirate problem follows this.Traditional Encryption technique cannot solve copyright protection problem entirely,which encrypts data only in transporting process,not only limiting people’s use but also having low level security. Digital watermarking technique is an efficiency tool of copyright protection.Being compared with Encryption,it overcomes the shortcomings of Encryption technique in multimedia copyright protection,and provides the complementary solution for Encryption technique.The digital watermarking technique on color image is studied in this paper. We analysis the features of color image,choose the area in which watermarking is to be embedded,improve the classify of image blocks on HVS. Then propose an adaptive color image watermarking algorithm based on DCT, which adaptive adjusts embedding threshold using the feature of HVS and ratio of RGB in 8 X 8 block,and embed watermarking in RGB channels. The experimental results show that the proposed algorithm has good robustness and invisibility.Finally,the thesis is concluded,together with some possible research directions in the future.更多还原