基于图像的信息掩密技术

【作者】 姚辉灿；

【导师】 慕德俊；

【作者基本信息】 西北工业大学 ， 控制理论与控制工程， 2004， 硕士

【摘要】 信息隐藏技术可以被广泛地应用于保密通信、版权保护、数字票据防伪等领域，对信息隐藏技术的研究具有重要的实用价值。 目前大部分的研究工作集中于数字水印技术，而用于秘密通信的掩密术则较少有人涉及。本文对信息隐藏领域的另一个重要方向——掩密技术进行了研究，着重讨论了其在数字图像中的应用。 首先，介绍了信息隐藏的相关基本知识。然后，分别在空间域和DCT域对于以静止图像为载体的信息隐藏技术进行了探讨。 在空间域内，利用人的视觉特性，我们提出了基于图象方差、图象平坦测度、模糊分类的隐藏算法，同时提出了基于差值矩阵的信息隐藏。 在频率域内，研究了基于DCT变换的信息隐藏技术，提出了改进的DCT自适应隐藏算法、DCT域奇偶性嵌入方法和改进的融合算法，同时提出了差值矩阵的DCT域的隐藏算法，给出了这些算法的信息嵌入与恢复过程，并对频率域内的这些隐藏算法的鲁棒性进行了分析。更多还原

【Abstract】 Information hiding techniques can be used in the fields of covert communication, copyright protection, digital receipt anti-counterfeiting, and so on. It’s of great value to study them.At present time, most of the studies focus on digital watermarking techniques, and few are done on steganography, one of the most important directions in the field of information hiding. This thesis concerns the steganography. We also place emphasis on its applications in digital images.Firstly, the relative basic knowledges of information hiding are presented, and then the techniques of digital images based information hiding in the domain of spatial and DCT (Discrete Cosine Transform) respectively.In spatial domain, according to the characteristics of HVS (Human Visual System), we introduce several approachs based on images’ deviation, images’ flatness measurement, fuzzy classification, and an approach based on difference matrix as well.In frequency domain, we research DCT based information hiding techniques, and then give an adaptive technique, and a parity based approach in the DCT domain, and an approach based on improved integration algorithm. We also propose an approach based on difference matrix in DCT domain, and show all the approaches to embed/detect the secret messages, and their robust analysises.更多还原