Binary Image Information Hiding Technology Research And Application

This thesis mainly focuses on steganography in binary image. Stegnoraphy are widely used in many domains. The very challenging problem, which hasn't been paid enough attention, is data hiding in binary images. There are so many differences between binary images and the gray-level or color images. The reason is that changing a pixel in such an image can be easily detectable .Information hiding in these images is easily detectable, robustless and has limited capacity. The purpose of this thesis is to enhance the robustness and the capacity of hidden messages and make the hidden message "blind" to human eye.First of all, the basis knowledge of stegnography is introduced. Then, the methods of hiding data in digital images and printed-images are proposed. An associated case of information hiding in binary images, which is mainly about digital seal for authentic document, is developed finally. Based on the previous work of steganography, this thesis has the following work:1. Introduce the ECC(Error Correction Code) into the field of information hiding in binary images. To decrease error rate, we preprocess the hidden information by convolutional code and decode them by Viterbi decoder.2. In spatial domain, we propose two methods: one is based on the boundary of image which can't be easily detectable; the other is based on the modules which holds a large capacity of hidden messages.3. After analyses the distortion of pixel values and geometry during the PS process, we achieve the RST (Rotation, Scale, Translation) invariants using characteristics of Fourier transformation, and extract secret information successfully.