摘要
提出了一种抗JPEG有损压缩的真彩图像半脆弱水印算法。采用YCbCr颜色空间,水印的生成和嵌入均在亮度分量进行。由图像基本特征生成水印,嵌入时对亮度分量进行分块DCT变换,选择每个分块的中频系数作为水印的嵌入位置。实验表明,该算法透明性好,而且对JPEG有损压缩具有较强的鲁棒性,对剪切、替换等恶意篡改做出报警并确定篡改位置。水印检测不需要原始图像,水印系统的安全性依赖于图像的特征及其置乱函数,因此,具有较高的安全性。
A semi-fragile watermarking algorithm for color image accept JPEG compression was presented, Based on the YCbCr color space, the watermark was generated and embedded in the luminance component. Watermarking was generated by the basic characteristics of Images. The luminance component was dealt with the DCT--block when embedded watermarking. And the middle frequency coefficient of each block was selected as the watermark embedding position. The experiments show that the algorithm, with an excellent transparent quality, is robust to JPEG loss Compression. Moreover, this algorithm is fragile to content modification （such as cropping, replacing） and can detect the tampered regions effectively. Without the original image, watermarking can be detected. The security of the watermarking system depends on the characteristics of the image and its scrambling function so that the system has a higher security.
出处
《计算机安全》
2009年第2期29-32,共4页
Network & Computer Security
