Audio steganalysis with Hausdorff distance higher order statistics using a rule based decision tree paradigm

The aim of this paper is to construct a practical forensic steganalysis tool for audio signals that can properly analyze the statistics disturbed by stego embedding and classify them to selected current steganographic methods. The objective of this paper is to prove that the choice of effective stego sensitive features and a proficient machine learning paradigm enhances the detection accuracy of the steganalyser. In this paper a rule based approach with a family of six decision tree classifiers viz., Alternating Decision Tree, Decision Stump, J48, Logical Model Tree, Naïve Baye’s Tree and Fast Decision Tree learner, to perform the detection of audio subliminal channel is introduced. In particular the higher order statistics extracted from the Hausdorff distance are investigated for an improvement of the detection performance, as competent audio steganalytic features. The evaluation of the enhanced feature space and the decision tree paradigm, on a database containing 4800 clean and stego audio files is performed for classical steganographic as well as for watermarking algorithms. With this strategy it is shown how general forensic approach can detect information hiding techniques in the field of covert communication as well as for DRM applications. For the latter case, the detection of the presence of a potential watermark in a specific feature space can lead to new attacks or to a better design of the watermarking pattern.