A Novel Semi-Fragile Watermarking Scheme with Iterative Restoration

In this paper, a novel semi-fragile watermarking scheme utilizing Iterative Restoration techniques is proposed. The scheme embeds a restricted set of restoration data in the transform domain of a cover image, which equates to a highly compressed copy of that image. If tampering occurs, the image is authenticated by comparing the extracted watermark data to encrypted data from a key file to detect changes. The restricted restoration data extracted from the image is then passed through traditional image restoration techniques such as Lucy-Richardson Iterative restoration and Blind Deconvolution, in an attempt to improve the restoration data before inserting back into tampered regions, to give an initial reconstruction of the manipulated locations. The technique can maintain a high watermarked image and restored region image quality of above 34 dB PSNR, as well as survive up to 30% JPEG Compression and other nongeometric attacks such as Gaussian noise, copy and paste, and region removal. The Average Detection Rate (ADR) is high, and Lucy-Richardson Iteration demonstrates up to a 25% improvement of subjective restoration quality compared to previous techniques such as LSB restoration schemes which use direct restoration techniques.