High Capacity Reversible Data Hiding with Optimal Bit Allocation

Abstract

Abstract This paper extends and improves the performance of a digital reversible watermarking algorithm presented in a previous work. The considered algorithm exploits the property of image histograms of some kinds of medical images which present many contiguous 0-runs, i.e., a comb structure in the gray level frequencies. The previous work suggested to perform some gray level histogram shifting according to a local optimization technique. In this paper we apply combinatorial optimization techniques to entire blocks of contiguous 0-runs, improving the payload capacity of the reversible data hiding method.