Reversible data hiding in encrypted AMBTC images

Signal processing in the encrypted domain has attracted a lot of attention due to the requirement for content security and privacy protection. Reversible data hiding in encrypted images (RDH-EI) is also a hot topic. However, the majority of the published techniques are designed for uncompressed images rather than JPEG-, VQ- and BTC-compressed images. In this paper, for the first time, a RDH-EI method for AMBTC images is proposed. In the proposed method, the higher mean and lower mean of a triple in an AMBTC-compressed image are encrypted by using stream cipher at first. Then, additional data can be embedded into the redundant space by using prediction error histogram modification technique. Experimental results and analysis demonstrate that, with the marked cipher-image, legal receivers are able to extract embedded data exactly by using a data hiding key, decrypt it to recover an image very similar to the original one by using an image encryption key, or extract additional data and recover the original image error free with both keys. The proposed method is applicable to real-time transmission due to the simple implementation of the algorithm and low computational complexity.