针对基于H.264/AVC帧内预测模式的信息隐藏算法,本文提出了一种信息隐藏检测方案.由图像残差DCT系数量化后的重建信号与原始信号差的期望为零,理论分析得到对于利用H.264/AVC帧内预测模式嵌入秘密信息的视频,经过H.264/AVC重压缩后,其载密的非最优帧内预测模式将转变为嵌入秘密信息前自然视频的最优预测模式.基于此推论及其实验结果,本文构造了帧内预测模式转移概率矩阵,并以此为特征结合支持向量机分类器进行视频信息隐藏检测.实验表明,本文算法对于不同类型的低嵌入率载密视频都具有很高的正确检测率.
A video steganalysis algorithm is proposed in this paper, which is used to detect the hidden in- formation via modulating H. 264/AVC intra-prediction mode. Based on the conclusion that as to the im- age's quantized differential DCT coefficient, the difference between the reconstructed signal and the o- riginal one has zero mean, it ~s found that the non-optimal intra-predietion mode which was modulated for covert communication will be converted to the natural optimum intra-prediction mode. Then the steganalysis scheme is proposed based on the transition probability matrix. Experimental results demon- strate that the algorithm is very effective in detecting hiding-data, moreover the embedding rate is very low.