Mean-quantization-based fragile watermarking for image authentication
Chun-Shien Lu · Optical Engineering · 2001
The existing digital image editing tools have made the authentication of digital images an important issue. The objective of this paper is to propose an image authentication scheme, which is able to detect malicious tampering while tolerating some incidental distortions. By modeling the magnitude changes caused by incidental distortion and malicious tampering as Gaussian distributions with small and large variances, respectively, we propose to embed a watermark by using a mean quantization technique in the wavelet domain. The proposed scheme is superior to the conventional quantization-based approaches in terms of the credibility of authentication. Statistical analysis is conducted to show that the probabilities of watermark errors caused by malicious tampering and incidental distortion will be, respectively, maximized and minimized when our new scheme is applied. Experimental results demonstrate that the credibility of our method is superior to that of the conventional quan...