Research On Robust Watermarking Arithmetic Without Original Image

With the development of the multimedia and the network technology, the application of the digital product is more and more wide. The security of the digital information becomes the concern in people's life. Especially, the copyright protection of digital product is more important and urgent. Of all the solution to the copyright protection, the watermarking technology is moreeffective one. Therefore, the study of this technology becomes a focus in the academic world. This dissertation has mainly studied digital watermarking without original image for stillimage and use tow-bit image as watermark. The main work includes the following four aspects:1) It encrypts the two-bit image of watermark by chaotic mapping based on the sensitivity of the chaotic mapping to the original value. This method is very simple and has good security.2) It educes a model of biased estimate for the embed method of ration and provides an effective evaluating method for watermarking without the original image. With it, the intensity of the embedding can be estimated.3) It gives a kind of arithmetic of watermarking based on SVD (Singular Value Decomposition). It uses the embedding model of ration instead of those traditional models. Experiments have indicated that it has good robustness, especially for JPEG compression.4) It gives another watermarking arithmetic without original image based on DWT (Discrete Wavelet Transformation) and the characteristic of human seeing and produces a satisfactory effect.