Detection of Information Hiding by Modulating Intra Prediction Modes in H.264/AVC

In the intra-frame coding of H.264/AVC, information hiding can be implemented by modulating the prediction modes of 4×4 luminance blocks. Since this kind of method has characteristics of high speed, good concealment and so on, it has become a great security threat. Therefore, it is necessary to study the 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. We found that the correlation among the prediction modes in different 4×4 luminance blocks, belonging to an intra-frame coding macroblock, was changed. According to this, we have designed statistical models to make quantitative extraction of these correlation characteristics. And a steganography detector was constructed based on the support vector machine. The experimental results show that the steganography detector constructed in this paper can achieve a detection accuracy of more than 90% when the embedding rate is larger than 25%. Keywords-information hiding; steganalysis; H.264/AVC; intra prediction; prediction modes modulating