Paper Title
Watermarking Scheme For Image Content Authentication

Our project proposes a semi-fragile watermarking scheme for image content authentication with tampering localization. Here we use a non-traditional quantization method to modify one of the chosen approximation coefficient of each non-overlapping block to ensure its robustness against incidental attacks and fragileness. The image content authentication starts with watermark extracting process using the parity of quantization results from the probe image, where the round operation is used to ensure the semi-fragile property. It then constructs a binary error map and computes two authentication measures with M1 measuring the overall similarity between extracted and embedded watermarks and M2 measuring the overall clustering level of tampered error pixels. These two measures are further integrated to confirm the image content and localize the possible tampered areas. Keywords—Quantization, Error map, Authentication measures