提出一种基于圆谐-傅立叶矩的抗几何攻击数字水印算法.利用图像函数的圆谐-傅立叶矩幅度的旋转、缩放不变性,在水印检测时,计算待检图像局部区域的圆谐-傅立叶矩,用所得的矩幅度与载体图像在该区域的矩幅角构成新的矩,通过与待检图像的矩进行比较,可以近似地恢复水印图像.实验结果表明,圆谐-傅立叶矩算法具有很好的旋转和缩放不变性,水印对旋转和缩放等噪声攻击具有较好的检测性.
This paper proposes a robust digital image watermarking algorithm against geometrical attacks based on radial Harmonic-Fourier moment.Due to its invariant property against rotation and scaling attacks,the Harmonic-Fourier moments of the partial of an image could be calculated during watermarking detection.New moments are formed with the Harmonic-Fourier magnitude moments of the original image and the moment angle,which could be used to compare to the moments of the original image creating a similar watermarking image.It has been shown by the experimental results that Harmonic-Fourier moments bear great robustness against rotation attacks and show scaling invariability.Watermarking yields great results during detection under rotation and noise attack.