The Hvs Perceptual Model And Robust Digital Watermarking

Robust Digital Watermarking is a branch of information security, and it is considered an alternative tool for protecting the copyright of multimedia .This paper researches the digital watermarking technique. At first, we introduce the basic character, theory. Then researches the arithmetic of robust digital watermarking based on transformation domain and Human visual system emphasized.The primary contributions of this paper contain the following points:(1) Introduce the principle of the ridgelet transform, and analyses the characteristic of its multicenter. Besides these, we gives the statistic result with experiment, and research the JND of visual model in the ridgelet domain.(2) We discuss digital spread-spectrum watermarking technique in the ridgelet domain based HVS. With this method we can adjust the strength of embedded watermark in according to the visual model in the ridgelet domain. And the extract arithmetic is not need the original image. Many experimental results indicate this algorithm is robust to some attacks.(3) Ridgelet transform decompose the spatial frequency domain into some subbands with different directions and frequencies. It is of benefit to anisotropic analysis of line in image processing. But it is helpless to the curve. In this paper, the original image is partitioned into small blocks to deal with straight edges. Then we find the most significant coefficients direction of an image with straight edges in every blocks, and eventually the watermark is embedded. The watermarking energy can be determined from the given Power Signal to Noise Ratio (PSNR).Robustness and invisibility are proven by experimental results.