一种新的分数阶Fourier域的Chirp类水印方案

提出了一种新的分数阶Fourier域Chirp类数字水印方案,该方案利用分数阶Fourier变换基函数的正交性和旋转相加性,在不同的分数阶Fourier域嵌入Chirp水印,并利用分数阶Fourier域Chirp信号的聚集性进行盲检测。接着结合该水印嵌入方案,利用分数阶Fourier变换的旋转相加性和酉性,推导出分数阶Fourier域水印容量的计算公式。仿真实验表明该算法由于可以选择嵌入在不同分数阶Fourier域,使得嵌入方法灵活安全,同时算法的不可见性好,对高斯白噪声干扰、裁剪及其它常见图像处理过程具有一定的鲁棒性。

Novel Chirp-typed image watermarking in fractional Fourier domain

A novel chirp-typed watermarking scheme which uses the properties of index additivity and orthonormality of fractional Fourier transform to embed watermark in the different fractional Fourier domain is presented.With the help of the property of the impulse characteristic in the fractional Fourier domain for Chirp signal,the watermark can be detected conveniently.The general capacity of the Chirp-typed watermarking scheme also be derived.Experimental results show that the proposed watermarking algorithm is not only of good imperceptibility and security,but also is flexible and secure,and can provide protection to some common image processing.