Reversible data hiding with automatic contrast enhancement and high embedding capacity based on multi-type histogram modification

Abstract

For an image, we can use reversible data hiding (RDH) with automatic contrast enhancement (ACE) to automatically improve its contrast by continuously embedding data. Some existing methods may make the detailed information in the dark regions of the grayscale image not well presented. Furthermore, these methods sometimes suffer from low embedding capacity (EC). Therefore, we propose an RDH method with ACE and high EC based on multi-type histogram modification. A pixel value histogram modification method is proposed to improve the contrast automatically. In this method, two-sided histogram expansion is used to improve global contrast, and then the histogram right-shift method is used to enhance the dark regions. Then, a prediction error histogram modification method is proposed to improve the EC. In this method, a new prediction method is proposed to better improve the EC. Experiment results show that compared with some advanced methods, the proposed method performs better.