Watermarking Algorithm For Image Content Authentication

With the development of Internet and powerful multimedia manipulation tools, the authentication watermarking technique, which for the image authentication, have been focused on and become an exciting research field of information hiding. The principles of authentication digital watermarking are described with their characteristics and designing requirements and limitations. At the same time, we summarized the basic algorithms techniques and discussed the recent frame of it and related requirements of the two developments of the two kinds of watermarking systematically in watermarking at integrated subjected to.The work is focused on the investigation of the visible authentication watermarking in different cases and requirement and can be summarized as follows:1. We put forward an algorithm that is combined with Rijndael code for removable visible watermarking according to a kind of integer lifting wavelet with parameter. The algorithm performs discrete cosine transform on sub image of host image, which is cover by visible watermarking, and compresses sub image by select the set of visually important DCT coefficients. Then, the algorithm hides the compressed sub image, which is encrypted by the hash function that is constructed by Rijndael code, in the high coefficient of wavelet domain. The experimental results have demonstrated that the sub image is high sensitive to the tempering and the legal user can recover host image.2. We propose an algorithm that is based on HVS model for translucent watermarking according to a kind of integer lifting wavelet with parameter. Before multiscale embedding, the algorithm performs lifting wavelet decomposition on both the host image and the watermarking. In low frequency sub band, the watermarking is embedded into host by the way of pixel-to-pixel embedding according to HVS model. In high frequency sub band, according to the local spatial characteristics of the host image and the watermarking, algorithm selects the set of visually important watermark coefficients by the specially JND and embeds. The experimental results have shown that the translucent watermarking in resulting image is very hard to remove Illegally. The pixel-based adaptive scaling of watermark image is most suitable to make the degree of marking applied variable according to both host and watermark features.Last, the thesis carried out a summary of the possible research direction of digital watermarking technique and pointed out further academic direction. The visible...