Digital Image Watermarking Method Based On Contourlet Transform Research

With the rapid growth of the information technology, the development of e-commerce, the increasingly digital media and the increasingly powerful digital media manipulation tools have made media security have been proposed, especially in the application of intellectual property right protection copyright protection and tamper-proofing. Information hiding and digital watermarking are new measures of digital media protection, which are processes of embedding hidden messages within digital media, such as text, images, video and audio. The hidden messages could be copyright information, user distributor identification number, company logo, personal signature, control bits, or any information considered useful for a specific application.In this paper, I introduce the digital watermarking technology development and algorithm; and then I studied the contourlet analysis and HVS theory. Under the researching above, a digital image watermark algorithm based on contourlet transform and HVS theory is referred. During the embedding of the watermarking, contourlet transform is done firstly and extract low frequency part as the embedded field, then the watermark is embed in the low frequency part of the original image.To test the affect of this algorithm,I have finished a lot of simulation experiment . The coefficient NC and PNSR are used to estimate the effect of the algorithm. Experimental dates show the designed algorithm maintain the image quality and is robust enough when facing JPEG compression, noise,cropping,image scaling and filtering attack etc.