Information Hiding And Digital Watermark

This paper has investigated some related problems of information-hiding and digital watermarking, the content of my works can summarized as follows:1. This paper gives an introduction about the characteristic and the application field of information-hiding and digital watermarking. And the correlative technique is introduced at length in this paper too.2. A digital watermarking sharing algorithm based on the Reed-Solomon code and liner transformation secret sharing scheme is presented in this paper. The algorithm applies the RS code and secret sharing to robust watermark, and it can reduce the error code rate in a certain extent. Since watermark is embedded in wavelet domain, it has a relative strong resistance to JPEG compression and JPEG 2000 compression. Moreover the algorithm encrypts the original watermark before embedding, so it has a high robustness and security.3. A fragile watermarking algorithm based on QR decomposition scheme is presented in this paper. It is a technique that applying the thought of the QR decomposition to the fragile watermarking. It can detect any modification of watermarked images while the quality of watermarked images still keeps high. To locate the changed position, a block-wise algorithm is proposed later, and its improved version can resist the cut-and-paste attack.4. A statistic algorithm is presented in this paper. This algorithm is based on statistic character and can resist cut-paste and erasing attacks effectively. The watermark is embedded in the wavelet transform coefficient, so it has a good effect on anti-compressing, especially on JPEG 2000. Because the algorithm adopts the method of disorder and statistic character, the watermark can be extracted even after cutting and erasing modification. This paper present a statistic watermarking algorithm for 8-bit gray image, and expand it to 24-bit colored image.5. At last, this paper analyzes the capacity problem of information-hiding and digital watermarking.