Study of digital image watermarking algorithm using fractal

This paper firstly introduces the research present situation and related concepts of the digital watermarking. In others´ algorithm study and on the basis of introducing chaos theory, the paper is based on the wavelet digital watermark of composite scrambling: firstly, it uses the cat transforming (Arnold scrambling) towards the binary watermarking images that were scrambling encryption, and then it produced a set of Logistic mapping random sequence, and the random sequence and scrambling encryption watermark are exclusive or the operation is in encryption. The wavelet transforming of original carrier image and the embedded watermark encryption are the final data to the low frequency sub-band of carrier image wavelet decomposition, and the embedding strength on the adjustment is according to the experimental results. From the watermark transparency and robustness of 2 experimental results, the experimental results show that it not only has good watermark transparency, but it also has strong robustness. After the introducing fractal theory, this paper puts forward the fractal combined with the digital watermark of wavelet domain: to make full use of wavelet transform after the direction with the son correlation, the decomposition of the series in wavelet decomposition is according to different coefficient construct wavelet tree, but it is in different wavelet tree series with the fractal structure. The watermark is embedded in the similar data matching tree. In the last algorithm simulation testing, the analysis of experimental results shows that the new algorithm has certain robustness and transparency.