关键词: 音频隐写分析, 二次嵌入, 小波分解, 线性预测

Abstract: Researching on the auto-correlation in steganographic software tools Hide4PGP，a group of new feature is proposed which is implemented by using support vector machine to classify with gradient energy variation and linear prediction statistics variation features after wavelet decomposition.The variations root in audio carriers with and without messages，and carriers already contain messages and re-embedded by Hide4PGP.This scheme can detect the existence of stego-audio embedded by Hide4PGP from clear-audio effectively.On the premise of high detection rate，an improvement of features by H.Farid has been made with a lower feature dimension and shorter classified time.

Key words: audio steganalysis, re-embedding, wavelet decomposition, linear prediction coding