Study On Color Digital Watermarking Algorithm Based On Scrambling And Wavelet Transform

With the development of computer network and internet technology, the protection of multimedia, image, audio and video content has become an urgent problem to be solved, so the digital watermark algorithm is also emerge as the times require. And also, the digital watermarking technique has become an important research and development field. Image copyright protection problem, especially in color image copyright protection, is to be solved. According to a given algorithm, digital watermarking technology embedding the information of certain significance into a carrier image, realizing the mage protection or certification, but the use value of image will not be affected.This paper first from the research significance and research status at home and abroad introduces the technology of image digital watermarking. The relevant overview, the basic algorithm, the attack methods and the evaluation standard of digital watermarking technology are introduced deeply. And then, the wavelet transform, Arnold transform and human visual system having important relation with the present study are introduced and analyzed deeply, laying a theoretical basis for the color image watermarking algorithm of this paper.Next, an algorithm for embedding a color image watermark is present in this paper. We employ the algorithm to separate the three color of a color watermark image, and then the Arnold transform was performed on the three components separated by three different secret keys. The three different secret keys of color components can enhance the security of the watermark information. And then, according to the characteristics of the human visual system, using the difference of sensitivity in the different regional of image after wavelet decomposition, the watermarking is embedded to the low and intermediate frequency domain of the wavelet transform, balancing the robustness and imperception of the watermark. Finally, we performed the simulation experiment of the watermarking algorithm in matlab platform. The simulation results show that the watermark algorithm can better maintain the image quality, and possess high safety and better robustness to noise pollution, image cropping and filtering attacks.