Based On Content Adaptive Digital Image Watermarking Technology

Digital watermark is a new subject in the information security field. It's a new technology which is used to protect copyright and authentication source. The author's copyright and personal information can be embedded in the products. But we can't percept it, only special software can pick it up. Digital watermark technique is a effective method for copyright protection, which has become a hot study field in multimedia security researchs and a key branch of hiding technology researchs .Wavelets be used widely in image processing due to its multiresolution and multiscale analysis property. Using discrete wavelet transform(DWT), We can manage the distribution and location of the watermark properly, and then get a robust and invisible marked image. Lifting scheme is a new methods to wavelet transform. Use this method, we can compute the wavelet transform simply,fastly without the use of fourie transform. So it is strongly recommended by the joint picture experts group(JPEG).Following the instructions of the current watermark technology,a new watermark technology which adaptive to specifics of the image is presented. The details of the algorithm are following:(1) After computing the wavelet trees, a properly intesive watermark will be embeded in the properly location. where the watermark be added to is decided by the complication of the original image, and the intensibility of the watermark is decided by the human vision system (HVS), the new method can guarantee the invisibility as well as the robustness of the watermark.(2)The watermark can also be detected adaptive to the image. The process of detecting is inverse to the embedding. if the order of the wavelet trees is not be known ,the watermark will not be detected easily.(3)Evaluated the algorithm. After the experiments and attack test, we can get that the algorithm has good tolerance to attacks such as cut, additive noise, and compress attacks.