A high payload reversible data hiding algorithm for homomorphic encrypted absolute moment block truncation coding compressed images

Abstract

With the aim to ensure privacy and security of secret message, an enhanced reversible data hiding algorithm in encrypted as well as compressed domain is proposed here. After compression of grey-scale image using absolute moment block truncation coding (AMBTC) method, pixels of AMBTC compressed image is segmented into two types - seed pixels (2k…255) and remaining pixels are called non-seed pixels. Now, embedded k, (k ≥ 1) binary bits of secret message by changed over it into base10 numeral framework at seed pixels of AMBTC compressed image whereas seed pixel is divided into two individual units which are encrypted through Paillier cryptosytem separately. Highlight of proposed method is to embed variable size secret message at seed pixels of AMBTC compressed image without any occurrence of overflow problem. Experimental study revealed that for all type of test images, proposed method altogether beated all the compared methods in its ability to embed secret message and precisely recover it with a PSNR value of $\infty $ dB between cover image and reconstructed image too.