Reversible data hiding in encrypted images (RDHEI) is a technique that not only allows the cover images can be fully restored without any loss of information after the embedded data has been extracted but also ensures the confidentiality within the cover images. This article proposes an RDHEI scheme combining adaptive ( n , n ) secret image sharing (SIS) manner. The content owner reserves part of the least significant bit plane (LSBP) in cover images by two most significant bit planes (MSBPs) compression using the median edge detector (MED) prediction method. To level up the privacy protection of n cover images, a two‐layer encryption method is utilized to generate n shares, that is, the self‐encryption and cross‐encryption. Moreover, our method can be applied on no matter how many of cover images. The secret data with identification can be concealed by the data hiders into the vacated LSB of their own shares. Through the cooperation of the overall shares, the receiver can retrieve the embedded secret data and recover the cover images. Experiment results reveal the security reliability of our approach and the outstanding performance when compared to some related methods. Also, the approach can be employed in color image domain.

Secret image sharing (SIS) is a technique used to distribute confidential data by dividing it into multiple image shadows. Most of the existing approaches or algorithms protect confidential data by encryption with secret keys. This paper proposes a novel SIS scheme without using any secret key. The secret images are first quantized and encrypted by self-encryption into noisy ones. Then, the encrypted images are mixed into secret shares by cross-encryption. The image shadows are generated by replacing the lower bit-planes of the cover images with the secret shares. In the extraction phase, the receiver can restore the quantized secret images by combinatorial operations of the extracted secret shares. Experimental results show that our method is able to deliver a large amount of data payload with a satisfactory cover image quality. Besides, the computational load is very low since the whole scheme is mostly based on cycling-XOR operations.