A Robust Fractal Color Image Watermarking Algorithm
A Robust Fractal Color Image Watermarking Algorithm
复制标题
DOI：
10.1155/2014/638174
复制
发表时间：
2014-03
影响因子：
--
通讯作者：
Jian Lu;Yuru Zou;Chaoying Yang;Lijing Wang
中科院分区：
文献类型：
--
作者：
Jian Lu;Yuru Zou;Chaoying Yang;Lijing Wang
水印的主要目标之一是在宿主图像的稳健性和高视觉质量之间实现更好的折衷。近年来，基于分形的灰度图像水印技术有了长足的发展。提出了一种基于人类视觉系统(HVS)的彩色图像分形水印方法。在该方法中，彩色像素被视为RGB空间中的三维矢量。采用3×3矩阵的一般形式作为标度算子。同时，将亮度偏移向量替换为范围块平均向量。然后，实现了一种正交化的分数维彩色编码方法，以获得很高的图像质量。我们还证明了正交化分形彩色译码是一个均值向量不变的迭代。因此，范围块均值向量是一个很好的隐藏水印的地方。此外，为了与人类视觉系统的特性保持一致，我们在CIE空间中进行了嵌入过程，并加入了JND轮廓来确保水印的不可见性。实验结果表明，该方法对各种典型攻击具有较好的鲁棒性，同时图像质量变化不明显。
One of the main objectives of watermarking is to achieve a better tradeoff between robustness and high visual quality of a host image. In recent years, there has been a significant development in gray-level image watermarking using fractal-based method. This paper presents a human visual system (HVS) based fractal watermarking method for color images. In the proposed method, a color pixel is considered as a 3-D vector in RGB space. And a general form of 3 × 3 matrix is utilized as the scaling operator. Meanwhile, the luminance offset vector is substituted by the range block mean vector. Then an orthogonalization fractal color coding method is achieved to obtain very high image quality. We also show that the orthogonalization fractal color decoding is a mean vector-invariant iteration. So, the range block mean vector is a good place for hiding watermark. Furthermore, for consistency with the characteristics of the HVS, we carry out the embedding process in the CIE space and incorporate a just noticeable difference (JND) profile to ensure the watermark invisibility. Experimental results show that the proposed method has good robustness against various typical attacks, at the same time, with an imperceptible change in image quality.