A Game-theory based Watermarking System and the Forensics for Printer Source Identification

• Main Authors: Liu, Jung, 劉蓉
• Other Authors: 蔡銘箴
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/05910637325833515390

博士 === 國立交通大學 === 資訊管理研究所 === 101 === Digital image processing generally applies various technologies which are widely used in many different fields. This thesis dicusses two topics of digital image processing for research purposes which include a game-theory based watermarking system and the forensics for printer source identification. In the first part of this study, we explore the inter-relationship between the robustness and translucence of visible watermarking and propose a novel watermarking algorithm named Adaptive Content and Contrast Aware (ACOCOA), which combines Human Visual System (HVS) and Noise Visibility Function (NVF). ACOCOA’s architecture uses game theory to resolve the conflicting interest of intensity and perceptual efficiency which provides the selection of optimal watermark intensity insertion for the decision maker. The second part of this study is to identify the printer sources for Chinese characters by applying statistical analysis on the Gray Level Co-occurrence Matrix (GLCM) and Discrete Wavelet Transform (DWT), which involves image processing techniques and data exploration methods to obtain 34 image features. Subsequently, the feature selection procedures are used to get a usable subset while only the most important features are systematically retrived. Finally, the classification technique of support vector machine (SVM) is utilized to identify the printer source. The experimental results demonstrate that the feasibility of the proposed approach: the game-theory architecture for visible watermarking system not only solves the previous problem of the watermarking energy insertion but also provides effectiveness and robustness for the watermarked images under attacks. In addition, the proposed method of the Chinese printed source identification analyzes the image characteristics of the printed documents to select the most important features for gaining the high accuracy ratio of source identification. In summary, this dissertation provides substantial contribution to the research field of digital content ownership protection and digital forensics.