**5. Conclusions**

In this work, an efficient separable reversible data hiding framework in encrypted images is proposed where Paillier cryptosystem is adequately used to preserve the privacy of the content in the cloud environment. Here, data extraction is accomplished in a separable manner, where the embedded additional data can be extracted using data hiding key and an independent complete image recovery is achieved using the private key.

In addition, the cost for encryption is reduced on the content owner's side (using limited processing and memory) with respect to Tai et al.'s scheme [24] by gracefully transferring the pre-processing step to the data hider side using cloud. Moreover, this proposed scheme exploits vast storage and memory resources available on the cloud. The proposed scheme was well explained with a real life application over cloud. Future works may include improving the efficiency of our scheme using new techniques in RDHEI.

**Author Contributions:** Conceptualization, A.N.K.; Data curation, A.N.K., M.I.N., A.M. and M.A.H.; Formal analysis, A.N.K. and A.M.; Funding acquisition, M.A.H.; Investigation, R.A.M.; Methodology, A.N.K.; Supervision, M.Y.F.; Validation, A.N.K.; Writing—original draft, A.N.K.; Writing—review & editing, A.N.K.

**Funding:** This research was funded by TEQIP-III of REC Ambedkar Nagar, grant number-TEQIP 3-RECABN and the APC was funded by TEQIP-III of REC Ambedkar Nagar.

**Acknowledgments:** The support of TEQIP-III of REC Ambedkar Nagar for this work is highly acknowledged.

**Conflicts of Interest:** The authors declare no conflict of interests.

### **References**


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