Semi-fragile Watermarking Algorithm Based on Arnold Scrambling for Three-Layer Tamper Localization and Restoration

Abstract

To protect the content integrity, authenticity and improve the effect of tamper localization and recovery, this paper designs and implements a semi-fragile watermark based on Arnold transformation, which is used to localize and recover tamper of confused image and plain-image. The sender encodes the watermark into the 2-bit least significant bit of the pixel of the original image, and the authentication watermark consists of the pixel value comparison result and the parity check code; the recovery watermark is the pixel value of the Torus image block. In the detection side, the plain-image adopts the stratified idea, carries on the three-level tamper localization and recovery, the third-party authentication institution can detect tamper of the scrambled image using the layer detection method, the receiver will detect the positioning result again. The experimental results show that the proposed algorithm can accurately locate tamper and realize the content recovery and effectively prevent the vector quantization attack. Compared with other algorithms, this algorithm has better effect of tamper localization and recovery.