Research Of Adaptive Multistep Information Hiding Algorithm In Digital Watermarking

With the booming development and extensive application of multimedia and computer networks, the digital medias(including digital image, digital vision and audio frequency) have been applied extensively. With the digitalization of information medias, we can get digital information conveniently and quickly. But the negative effect of digitalization technology has made the copyright and security of digital information products be widely threatened now. In the open computer network environment, it has become much urgent for us to provide efficient copyright and security protection means for the digital information products. The traditional methods of encryption have already not satisfied the needs of practice. As a effective complimentarily means of the traditional method of encryption, the digital watermarking technology has already arouse people more and more interest in recent years.In this paper, We make use of the good performance of the chaotic sequence as a method of confusing and the HVS visual masking, and present a algorithm of image watermark based on the technology of multistep information hiding. In this algorithm, at first, we make the transformation of DWT on the original image, then select some sub image of the DWT, and make the transformation of DCT on them, and use chaotic sequence to confuse the initial watermark; then, based on the HVS visualmasking and the characteristic of the image edge, digital watermark is embedded to the confused DCT middle frequency coefficients of the block-DCT. The simulation results show with this algorithm, watermark can achieve better robust and invisible. It's also has stronger ability of anti-attack.