Blind gain invariant image watermarking using random projection approach

摘要

Digital Watermarking helps us to protect the intellectual property of distributed media by hiding a piece of information within it. In this paper, a robust image watermarking method based on the projection of samples of the host signal into a random space is proposed. First, the vector constructed by the host signal samples is projected on two random vectors. Then, to embed a watermark digit, the ratio of the two projections is quantized. In order to preserve the imperceptibility of the watermark, analytical calculations are made to minimize the resultant distortion. To extract the watermark, a maximum likelihood detector is designed and accordingly the error probability of the proposed method is derived. The performance of the proposed method is investigated in terms of watermark to noise ratio. It is shown that there exists a trade-off between distortion and capacity without any concerns about the error probability. Experimental results verify the theoretical achievements of this study and show the superior performance of the proposed method in comparison to the state-of-the-art methods. Simulation results also demonstrate the robustness of the proposed method against common attacks such as filtering and geometrical attacks. (C) 2019 Elsevier B.V. All rights reserved.