High-Fidelity Reversible Data Hiding Using Block Extension Strategy

Abstract

Improved pixel value ordering (I-PVO) is a popular reversible data hiding scheme which uses sorting-based prediction error expansion method to provide high fidelity marked images. In this paper, a new reversible data hiding scheme for large payload is presented. The proposed scheme first embeds the secret data into 2×2 sub-block using I-PVO method and then extends the size of block 1×2 pixels if the noise level of the sub-block is equal to `0'. The additional pixels of the block are modified to embed the secret data using the proposed block extension strategy. The proposed block extension strategy uses a new prediction and embedding method that can hide the secret data with minimal distortion. As a result, high embedding capacity along with high quality marked image is achieved. The experimental results show that the proposed method has superior performance over the previous PVO based methods.