一种用于JPEG2000认证的半脆弱数字水印

Semi-Fragile Watermarking for JPEG2000 Image Authentication with Precise Localization

提出了一种抗JPEG2000有损压缩的半脆弱图像数字水印算法。该算法利用HASH函数对初值的敏感性,并根据量化不变性,将预先量化小波系数和水印密钥相结合,通过HASH函数根据所有的小波系数生成认证水印。根据水印调整小波系数的大小,完成双重水印的嵌入调制。实验结果表明,该算法对JPEG2000有损压缩具有良好的鲁棒性,同时可对图像内容的恶意篡改进行检测与精确定位,并能够区分篡改强度。

A semi-fragile image watermarking technique that accepts anti-JPEG2000 lossy compression was developed.With the high sensi-tivity on initial value of Hash function and the invariant properties,the pre-quantified the wavelet coefficients and a watermarking key are combined as the initial value of Hash function for generating the watermark.The doubled watermarked image was obtained by modifying the wavelet coefficients according to the watermark..Experimental results showed the proposed technique was robust against anti-JPEG2000 lossy compression,but sensitive to the malicious attacks on the watermarked image.At meantime,it can localize the tampers correctly and accurately,and be able to distinguish the intensity of falsification.