An improved block based joint reversible data hiding in encrypted images by symmetric cryptosystem

Real-Time Error-Free Reversible Data Hiding in Encrypted Images Using (7, 4) Hamming Code and Most Significant Bit Prediction

“…To recover the image and extract the embedded bits after decryption, the flipped pixels are detected by estimating the smoothness of each block. The method in Reference [13] was improved in Reference [14][15][16][17]. In Reference [14], the side-match strategy was used to improve the precision of the estimation of the smoothness of the blocks.…”

“…In Reference [16], the approach used to select the pixels to be flipped was improved for better quality of the decrypted image and the smoothness of the block was estimated based on the content of the image to reduce errors associated with extracting the bits. In Reference [17], each block was divided into two or more sub-blocks. By selectively flipping three LSBs of the sub-blocks, two or more bits can be embedded into one block to improve the capacity.…”

An Improved Reversible Data Hiding in Encrypted Image Method Based on Block Selection

“…[24] similarly presents a new fluctuation function for the reduction of the error rate. To improve the embedding capacity, Bhardwaj et al [25] proposed a new RDHEI method by segmenting each non-overlapping pixel block into n sub-blocks such that n (n = 2, 3, 4, • • • ) bits can be embedded.…”

“…For the aforementioned methods [21]- [25], the block size must be large enough to guarantee reversibility for the reason that all blocks are used to carry additional data. In this way the embedding capacity benefits little from the improvement of fluctuation function.…”

“…Fig. 1 provides the general sketch of the previous methods [21]- [25]. As it is shown there are three participants.…”