A block-wise cyclic shifting-based reversible data hiding scheme (BCS-RDH) for secure medical image transmission

Reversible data hiding (RDH) has received serious attention from researchers in the past few years. The RDH method that can store additional details in encrypted images is a challenging area since the concealing rate is too low for such approaches. This research work introduces a new RDH method called block-wise cyclic shifting-based RDH (BCS-RDH), which can embed additional data in an image through a block-wise right cyclic shifting operation on the partitions of size S × S pixels. The BCS-RDH can embed any integer value in the range [0−(S2−1)] and it ensures a concealing rate of (Log2 S2)/S2 bits per pixel (bpp). The BCS-RDH ensures the retention of the histogram and entropy of the encrypted image since the spatial rearrangement does not alter these two parameters, ensuring that the RDH process does not compromise the security aspects. The image reconstruction and the retrieval of the hidden details are done at the recipient by analyzing all the left-cyclic shifted partitions after attempting the decryption. The experimental study is carried out on standard images, and we rigorously analyzed all the key parameters. The study shows that the BCS-RDH surpasses several existing well-known RDH approaches.