Self-embedding watermarking scheme for colour images by bi-level moment-preserving technique

In this study, the watermarking issue for colour image authentication is presented to resist malicious tampering. The objective of this study is to preserve the colour moments such that the tampered region of the colour image can be recovered with high quality. An input colour image is first partitioned into non-overlapping blocks for watermark embedding. The watermark information embedded into each block consists of the authentication data and the feature information that is given by the bi-level moment-preserving technique. In the proofing process, the authors propose a two-stage dual parity-check method and use morphological operations to prove the validity of the image blocks. The former is proposed to check two set dual authentication data for obtaining better results of tamper proofing and the latter is used to further improve the neighbourhood connectivity of the results. In the recovery process, the feature information of each block is rebuilt for reconstruction. The simulation results show that the proposed self-embedding watermarking scheme is able to effectively prove the tempered region with high detection rate and recover the tempered region with high quality. Meanwhile, the proposed scheme outperforms the relevant existing methods.