Semi-fragile watermarking for color image authentication and recovery

In this paper, an efficient semi-fragile watermarking scheme for color image tamper proofing and high-quality recovery is proposed. The scheme is efficient because the validity of image blocks is simply proofed by using a dual-option parity check method and morphological operations. The former is used to generate authentication information for obtaining better results of tamper proofing and the later is used to further improve the neighborhood connectivity of the results. To achieve high-quality recovery of the tampered image, the feature information of the host color image and its corresponding block-edge-pattern information are properly organized to embed into three color components of the host color image. Meanwhile, the embedding information are appropriately distributed over luminance and chrominance components of the color image in the YCbCr color space such that the quality of the watermarked image can be better obtained. The simulation results show that the proposed watermarking scheme can effectively proof the tempered region with high detection rate and can restore the tempered region with high quality.