Reversible data hiding based on histogram shifting with sorted pairs of points

Abstract

In recent years, Reversible Data Hidden (RDH) has been paid more and more attention by researchers. Existing RDH algorithms based on histogram shifting require that there should be no overlap between the multiple pairs of maximum and minimum points, so that the embedding capacity is relatively small. In order to improve the embedding capacity, we propose a histogram shifting technique which allows the region between the multiple pairs of maximum and minimum points to be overlapped. This scheme simplifies the process of selecting frequency points. It only needs to find some maximum points and minimum points, and one maximum point matches another minimum point according to their distance. For each pair of maximum and minimum point, histogram shifting is applied to embed the secret information. The experimental results show that the embedding capacity is greatly improved while the image quality reduces slightly.