基于Zernike矩的抗旋转攻击图像感知哈希算法

Zernike moment based image hash algorithm resistant to rotation

摘要:

以Zernike矩为特征图像感知哈希算法,由于Zernike矩对图像旋转具有不变性,使得算法具备了旋转攻击下的鲁棒性;同时由于Zernike矩是图像的正交表示,能够很好地提取图像的内容,使得算法具有良好的区分性.算法首先将图像归一化,然后提取图像Zernike矩作为特征,经过密钥置乱后,对特征进行量化生成哈希串.算法在100幅图像组成的样本集上进行了测试,结果表明本文算法在旋转攻击下误接受率小于4%,匹配错误率在10-9数量级.说明基于Zernike矩的图像哈希算法能够同时满足对旋转攻击鲁棒和区分不同图像的技术要求.

Abstract:

In this paper,we proposed a novel image hash algorithm based on Zernike moments.We employ Zernike moments to represent the image content for the reason that it is the projection of the image under a group of orthogonal basis.Thus,the discrimination of proposed algorithm is improved.Meanwhile,benefited from the invariance property of Zernike moment under affine transform,our algorithm is robust to rotation attack.In the proposed method,the hash string is generated from the Zernike moments of the normalized input image.Secret key is also introduced to ensure the security of the hash method.In the experiments,the method is tested by 100 sample images.The false accept rate under rotation attack is less than 4%.The error recognizing rate between different images is about 10-9.Experimental results prove that our algorithm has great robustness and discrimination.