利用新的和整合性的資訊隱藏技術做影像版權保護、秘密傳輸及竄改偵測之研究

Abstract

由於數位影像在網際網路的發展，我們可藉由這些影像來傳遞資訊。同時，也由於數位科技的進步，這些影像可能會被複製，甚至是被竄改。因此，在本論文中，我們會提出一些方法來達到秘密傳輸的目的，也會提出一些方法來保護影像的版權並指出影像被竄改之處。針對灰階影像，我們利用可視浮水印及人類視覺模型來證明影像的版權及偵測影像被竄改處。接著，針對黑白影像，我們提出了一種改變一個3´3影像區塊裡面的一個像素來達到隱藏兩個位元的資料隱藏方法，也提出了一種重排影像區塊裡面的像素點的影像驗證方法來證明黑白影像的完整性。然後，我們會分別針對BMP、JPEG、GIF影像提出一種整合性的資料隱藏技術來藏入不可視浮水印、可視浮水印、註解資訊及驗證信號。相關的實驗結果可證明所提方法的可行性。最後，我們也提出影像的多家授權機制及影像認證中心的功能來保護影像的版權。

Because of the proliferation of digital images on the Internet, people can carry and transmit information by digital images conveniently. For this purpose, some methods for covert communication are proposed in this study. Besides, with the advances of digital techniques, digital images may be copied or tampered with illegally. To solve such problems, some methods for copyright protection and tampering detection for various types of images are proposed in this study. For grayscale images, a method based on visible watermarking techniques and a human visual model is proposed to protect copyrights and detect image alterations. For binary images, a data hiding method is proposed to embed up to two bits in a 3´3 image block by changing at most just one bit in a block. An authentication method for verifying the fidelity and integrity of binary images is also proposed, which creates authentication signals by rearranging the pixels in image blocks. Three methods integrating various data hiding techniques to embed invisible watermarks, visible watermarks, annotations, and authentication signals into three types of images are finally proposed. Good experimental results prove the feasibility of the proposed methods. Finally, some mechanisms for multiple authorizations of images are proposed and some functions of an image authentication center are also suggested.