  This work proposes a high-capacity scheme for separable reversible data
hiding in encrypted images. At the sender side, the original uncompressed image
is encrypted using an encryption key. One or several data hiders use the MSB of
some image pixels to hide additional data. Given the encrypted image containing
this additional data, with only one of those data hiding keys, the receiver can
extract the corresponding embedded data, although the image content will remain
inaccessible. With all of the embedding keys, the receiver can extract all of
the embedded data. Finally, with the encryption key, the receiver can decrypt
the received data and reconstruct the original image perfectly\ignore{ without
the data embedding key(s) }by exploiting the spatial correlation of natural
images. Based on the proposed method a receiver could recover the original
image perfectly even when it does not have the data embedding key(s) and the
embedding rate is high.
