Self-recovery Fragile Watermarking Using Block-Neighborhood Tampering Characterization

Abstract

In this paper, a self-recovery fragile watermarking scheme for image authentication is proposed to improve the performance of tamper detection and tamper recovery. The proposed scheme embeds the encrypted feature comprising 6-bit recovery data and 2-bit key-based data of the image block into the least significant bits (LBS) of its mapping block. The validity of a test block is determined by comparing the number of inconsistent blocks in the 3×3 block-neighborhood of the test block with that of its mapping block. Moreover, to improve the quality of the recovered image, the 3×3 block-neighborhood is also used to recover the tampered blocks whose feature hidden in another block is corrupted. Experimental result demonstrates that the proposed method outperforms conventional self-recovery fragile watermarking algorithms in tamper detection and tamper recovery under various attacks. Additionally, the proposed scheme is not vulnerable to the collage attack, constant-average attack and four-scanning attack.