Research On Content Adaptive ICA Digital Image Watermark Algorithms

Digital watermark is one of the hotspot technologies in research regions of authority protection and information safety. It has the advantages of robustness and frangibility and it can be embedded into text, image, audio, video and software to protect the authority. First,it is introduced some types of watermark model. Image watermark in wavelet domain is analyzed by heretical means and the basic schemes for it are tested by software simulation. Second, it's presented the algorithm of Independent Component Analysis (ICA). It is also discussed the model basis, restrict condition and process of solving and the effectiveness of blind separation has been proved by simulation. Third,a wavelet domain watermark scheme which is based upon the spatial watermark model founded on ICA is presented. In the process of embedding, the images were analyzed by wavelet transform and wavelets coefficients of image and watermarks were mixed which came from ICA and original image respectively. In the process of extracting, the watermarks are gotten by ICA in wavelet domain. At last, it is testified by comparing the simulation results when the watermark is attacked by noise, rotation and cropping. The experiment outcome shows that the scheme could extract watermark correctly and with good characteristic of robustness.