A Novel Self-Embedded Dual Watermarking Method for Image Tamper Detection and Recovery

Abstract Digital images have been used frequently in our daily lives. Manipulations on images can easily be made through various image-editing software. Detecting and recovering these manipulations are an important issue. In this paper, a novel self-embedded dual watermarking method based on discrete wavelet transform for tamper detection and recovery is proposed. This method is a block-based approach. It divides the input image into non-overlapping blocks. The watermark used for each block is constructed using recovery and authentication information that are obtained from the considered wavelet transformed block. The recovery information is generated from the seven MSBs of the LL1 coefficient. The first five bits of the LL1 and block number are used to generate the authentication bits. The authentication bits of each block are embedded into the block itself, while the recovery bits are embedded in two different blocks determined from the lookup table. The advantage of embedding the same information of a block into two different blocks is that when one of the blocks is damaged, the information can be recovered from the other one. The developed technique is evaluated under various attacks such as cropping and collage and compared with several state-of-the-art methods. Experimental results show that the proposed approach can easily detect the tempered areas of the watermarked image against various attacks and effectively recover those areas using the self-embedded dual watermark. The results obtained certify the considerable accuracy and feasibility of the proposed technique.