A reversible watermarking prediction based scheme using a new sorting technique

Abstract

The prediction error expansion technique is one of the reversible watermarking techniques. The sorting technique exploits the correlation between neighboring pixels for optimizing embedding order hence sorting is a fundamental step to enhance the embedding capacity and visual quality. In this paper a new sorting technique is designed to improve the hiding capacity and visual quality. Using of prediction expansion, histogram shifting and our new sorting technique produces superior results than several methods. We use a new measure for sorting the cells and we show that using only local variance values for sorting is ineffective in some cases. By using the new measure we can solve this problem and lead to more efficient sorting procedure. Experimental results show the efficiency of our proposed sorting procedure.