Detection of quantization index modulation steganography in G.723.1 bit stream based on quantization index sequence analysis  

作　　者：Song-bin LI Huai-zhou TAO Yong-feng HUANG 

机构地区：[1]Department of Electronic Engineering,Tsinghua University,Beijing 100084,China [2]Tsinghua National Laboratory for Information Science and Technology,Beijing 100084,China

出　　处：《Journal of Zhejiang University-Science C(Computers and Electronics)》2012年第8期624-634,共11页浙江大学学报C辑（计算机与电子（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (No. 60970148);the National High-Tech R&D (863)Program of China (No. 2011AA010704)

摘　　要：This paper presents a method to detect the quantization index modulation(QIM) steganography in G.723.1 bit stream.We show that the distribution of each quantization index(codeword) in the quantization index sequence has unbalanced and correlated characteristics.We present the designs of statistical models to extract the quantitative feature vectors of these characteristics.Combining the extracted vectors with the support vector machine,we build the classifier for detecting the QIM steganography in G.723.1 bit stream.The experiment shows that the method has far better performance than the existing blind detection method which extracts the feature vector in an uncompressed domain.The recall and precision of our method are all more than 90% even for a compressed bit stream duration as low as 3.6 s.This paper presents a method to detect the quantization index modulation （QIM） steganography in G,723.1 bit stream. We show that the distribution of each quantization index （codeword） in the quantization index sequence has unbalanced and correlated characteristics. We present the designs of statistical models to extract the quantitative feature vectors of these characteristics. Combining the extracted vectors with the support vector machine, we build the classifier for detecting the QIM steganography in G.723.1 bit stream. The experiment shows that the method has far better performance than the existing blind detection method which extracts the feature vector in an uncompressed domain. The recall and precision of our method are all more than 90% even for a compressed bit stream duration as low as 3.6 s.

关 键 词：STEGANALYSIS Quantization index modulation （QIM） G.723.1 Codeword distribution characteristics 

分 类 号：TN918[电子电信—通信与信息系统]