摘要
提出了一种基于图像Hadamard变换的半脆弱水印算法。首先对图像进行分块Hadamard变换,选取分块低频分量进行量化,并Hash操作生成具有固定长度的摘要,然后将摘要的若干位作为水印在密钥的作用下嵌入到其它分块的中频系数里形成含水印图像。实验结果表明,算法对常规操作鲁棒,能够检测对内容的恶意篡改,定位能力好,误检和漏检率低,安全性好,可作为图像内容真实性认证的算法。
This paper proposed a semi-fragile watermarking algorithm based on Hadamard transform.First,the original image is subdivided to blocks and executed Hadamard transform,then selected the lowest frequency components of specific positions from the blocks and quantized,encrypt them by the Hash function which generates the message digest with fixed length.Finally,chooses some bits of the message digest as the watermark and hides it into other Hadamard blocks of the mid region under key effect.Experiments show tha...
出处
《杭州电子科技大学学报（自然科学版）》
2009年第4期58-62,共5页
Journal of Hangzhou Dianzi University：Natural Sciences
关键词
哈达玛变换
图像认证
半脆弱水印
哈希函数
Hadamard transform
image authentication
semi-fragile watermark
Hash function
