RST-Invariant Semi-fragile Image Authentication Based on DWT-Coefficient Quantization

In this paper, we propose an image moment-based geometric normalization to be applied before embedding and extracting a digital watermark in the DWT-domain of JPEG2000. A semi-fragile signature, generated from the normalized host signal, afterwards, is embedded for image authentication. The new system is tested extensively and performance results are compared to those of methods proposed by other authors. Our new semi-fragile image authentication is robust against non-malicious modifications, such as lossy compression, noise, image blurring and sharpening, changes of luminance and contrast as well as scaling, rotation, translation, and shearing.