Three-dimensional histogram shifting for reversible data hiding

Histogram shifting is an important method of reversible data hiding. However, every pixel, difference, or prediction-error is respectively changed to hide a data bit in the traditional histogram shifting, which constrains the capacity-distortion embedding performance. An efficient three-dimensional histogram shifting is proposed for reversible data hiding in this paper. Take H.264 videos as covers to show this method. In a 4 × 4 quantized discrete cosine transform luminance block, which is not inferred by others, three alternating current coefficients are selected randomly as an embeddable group. According to the different values of the selected coefficient groups, they could be divided into different sets. Data could be hidden according to these sets. In the traditional histogram shifting, only one information bit could be hidden with at most one modification of one coefficient, whereas two data bits could be hidden at the same cost by using the proposed scheme. The superiority of the presented technique is verified through experiments.