In modern societies, due to the explosively increasing amount of usage of multimedia content, the security of multimedia content has become a very important issue. Nowadays, there are two major types of technologies which can provide solutions to the security problem. One is encryption and the other is watermarking. This thesis is focused on a special kind of watermarking method called halftone image watermarking. In halftone image watermarking, a type of method, which we usually call them halftone visual watermarking (HVW), is used to embed a secret pattern into halftone images (typically two) such that when the halftone images are overlaid, the secret pattern will be revealed. Here, we firstly propose a general formulation for HVW problems. Then we propose advanced HVW metho...[ Read more ]

In modern societies, due to the explosively increasing amount of usage of multimedia content, the security of multimedia content has become a very important issue. Nowadays, there are two major types of technologies which can provide solutions to the security problem. One is encryption and the other is watermarking. This thesis is focused on a special kind of watermarking method called halftone image watermarking. In halftone image watermarking, a type of method, which we usually call them halftone visual watermarking (HVW), is used to embed a secret pattern into halftone images (typically two) such that when the halftone images are overlaid, the secret pattern will be revealed. Here, we firstly propose a general formulation for HVW problems. Then we propose advanced HVW methods for both error diffused halftone images and dot diffused halftone images.