基于离散余弦变换的盲水印算法研究

基于离散余弦变换(DCT)方法对水印算法进行了研究,提出一种新的将水印嵌入到分块DCT相位成分的盲水印算法.引入了局部峰值信噪比来确保嵌入水印的不可见性,同时根据混沌系统对初始条件极度敏感的特点,以一维混沌映射的初始条件作为密钥,由产生的混沌序列来确定水印嵌入的子块位置,进而提高算法的安全性.仿真结果表明:采用该算法实现的水印对常见的处理和几何变换具有很好的鲁棒性.

Blind watermarking algorithm based on DCT

A watermarking scheme based on the discrete cosine transform(DCT) was studied.A new blind watermarking algorithm by embedding the watermark into the phase components of DCT was proposed.The local peak signal-to-noise ratio(LPSNR) was adopted in the scheme to ensure the imperceptibility.Since the chaotic system was sensitive to the initial conditions,the initial value of a one-dimensional chaotic map was selected as the secret key and the output sequence of the chaotic map was used to determine the position of sub-blocks.Simulation results showed that the watermarking scheme was robust to typical image processing and geometric transform.