Reversible data hiding with multiple data for multiple users in an encrypted image

Abstract

This article presents a new method which embeds multiple data from multiple users in an encrypted image. Here, the data from several users is embedded into an encrypted image. Initially, the image is encrypted by the owner followed by embedding phase, where the encrypted image is divided into four sets. Two of them are used to embed the secret data, while others are remain unaltered. The secret data from multiple users are embedded into Most Significant Bit (MSB) of the encrypted image using their location maps. In the extraction phase, an individual owner can extract the data from the encrypted image using the assigned private key. Subsequently, in the image decryption and recovery phase, images can be recovered using the unaltered neighbor pixels. However, the secret image can be recovered losslessly using the encryption key only. The proposed scheme allows the extraction of the embedded information only for the authorized user out of several users without knowing the cover information. Various simulations have been made related to this, which show the high embedding rate and accuracy.