Steganalysis of prediction mode modulated data-hiding algorithms in H.264/AVC video stream

Abstract

In the intra-frame coding of H.264/AVC, information hiding can be implemented by modulating the prediction modes of 4 × 4 luminance blocks. Because such kind of methods has characteristics of high speed, good concealment, and so on, it is very suitable to build the covert communication system based on video communications and brings a great public security threat. Therefore, it is important to study its steganalysis method. In this paper, we first analyzed the changes of remarkable characteristics in intra-frame coding caused by modulating intra-prediction modes for information hiding, and found that the inherent correlation among the prediction modes in different 4 × 4 luminance blocks belonging to an intra-frame coding macroblock was changed. According to several different positional relationships of the adjacent 4 × 4 blocks in spatial domain, we designed statistical models corresponding to the prediction mode correlation to make quantitative extraction of these correlation characteristics. An information hiding detector was constructed based on the support vector machine. Based on the constructed detector, the experimental results show that the mean of the detection accuracy, recall ratio, and precision ratio are all excellent for different test video sequences.