## 4 Proposed Methodology
A photo response non-uniformity-based forgery detection method in image watermarking also proves their effectiveness in detecting forgeries of digital images [40]. User-unaware watermarks can be effectively used in detecting fake profiles of any social network, where the photo response non-uniformity method shows more effectiveness compared to the state-of-the-art methods [41]. In the future, we will work with generative adversarial networks, photo response non-uniformity, or user-unaware watermarks to enhance the robustness of our method. Also, block truncation coding is used to protect multimedia content from unauthorized access [42]. Moreover, the adaptive information hiding technique is currently used to secure embedded information based on the feature extraction method [43]. In the future, we will enhance the security of the system with a block truncation coding framework and IoT or visible light communication-based adaptive security techniques. If we remove the watermark using the same Arnold mapping process that was used to embed it, we might not be able to restore the original unwatermarked image that reflects the reversible image watermarking. In the future, we will work with an optimized scaling factor or adaptive techniques to choose the value of the watermark strength alpha. In addition, we will work with blind reversible image watermarking to reconstruct the original host or the unwatermarked image after watermark extraction. Moreover, we will incorporate RGB color images and other multimedia elements into this hybrid grayscale image watermarking method. Conceptualization, M.B. and M.S.U. ; Methodology, M.B., S.B.S. and J.F. ; Software, M.B., S.B.S. and J.F. ; Validation, J.F. ; Formal analysis, M.B. ; Investigation, M.B., M.S.U. and M.W. ; Resources, M.S.U. and T.J.; Data curation, S.B.S. and J.F. ; Writing--original draft, M.B. ; Writing--review & editing, T.J., A.B. and M.W. ; Supervision, M.S.U. ; Project administration, M.S.U. ; Funding acquisition, A.B. All authors have read and agreed to the published version of the manuscript. This research is partially supported by the Australian Research Council Discovery Project: DP210101864. Data are contained within the article. The authors are thankful to the Information and Communication Technology Division of the Government of the People's Republic of Bangladesh for a Ph.D. fellowship to [PERSON]. The authors declare no conflicts of interest. ## References

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