Research On Digital Image Watermarking Algorithm Based On Chaos Theory And Wavelet Transform

With the advent of the digital age. traditional media content gradually transition from traditional analog signal to digital signal, digital media is very easy to spread, copy and modify, which makes the pirates provide a good opportunity, however at the expense of the original authors interests. Therefore, how to prevent the copy of the digital media to achieve copyright protection becomes very important. Traditional password-protected technology is no longer able to meet the requirements of copyright protection, then an urgent need of a new technology as a supplement, digital watermarking technology is appear in this background.The digital watermarking algorithm based on chaos theory and wavelet transform is the main content of research in this paper. First, Use of chaos theory to do some preprocessing of the watermark, Here, Use of the Arnold Transform or Logistic map for scrambling digital watermark to ensure the security of the watermark, because the wavelet transform in image compression JPEG2000standard has a unique advantage, therefore, the digital watermarking algorithm of the article using the wavelet transform of the carrier image, so that is conducive to enhance its robustness. On the specific implementation, first, digital carrier image for the three-layer wavelet change, and then the watermark that has been transformed is embedded into low frequency coefficients of three-layer wavelet transform, because of Human visual sensitivity to low-frequency, the article process low frequency coefficients of the watermark image and host image orderly, then, according to the requirements embedded in the corresponding position, so to ensure that the watermark is not visible at the same time, can also increase the embedding the amount of the watermark.Through a variety of attacks Experimental results show that the digital watermark algorithm is not only better security, and under the premise of ensuring the watermark is not visible, we can embed more watermark information in the wavelet coefficients which make the watermark have more good robustness.