Semi-fragile watermarking for image content authentication

In this paper, we propose a quantization-based semi-fragile watermarking algorithm for content authentication. The watermark can be blindly extracted. The formulation of judge threshold is given from the point of probability theory. The tempered areas of watermarked image can be distinguished by the predefined threshold. Our scheme is robust to incidental manipulations while fragile to malicious distortions, and can distinguish the distortions caused by great incidental processing with the malicious tempering. The advantage of our scheme is compared with other algorithms in the last.