基于扩频和离散余弦变换的稳健水印算法

Steady Watermark Algorithm Based on Spread Spectrum and DCT

提出一种基于扩频、Logistic映射和离散余弦变换(DCT)的稳健水印算法。首先使用扩频及Logistic映射对水印信息进行置乱,增强水印信息的不可见性及鲁棒性,然后在载体图像中频中嵌入水印,水印提取时进行奇偶校验。结果表明:该算法对高斯噪声、压缩、剪切等攻击具有较好的鲁棒性。

A steady watermark algorithm based on spread spectrum, Logistic mapping and discrete cosine transform （DCT） was proposed. The spread spectrum and the Logistic mapping were employed to scramble watermark information for the enhancement of invisibility and robustness. Then, the watermark was imbedded into the intermediate frequency of carder image. The successful parity check should be done when extracting watermark. The results indicate that the algorithm has good robustness for Gaussian noise, compression, sheafing and other attacks.