针对MIDI音频的LSB匹配隐写,提出一种基于力度平滑度转换率的隐写分析方法,原始MIDI音频力度分量分布不规则性强,载密后不规则性减弱,用力度分量平滑度转换率表征MIDI音频不规则性。通过实验训练转换率阈值并进行分类,鉴别MIDI音频是否载密。实验表明,当LSB匹配隐写嵌入容量超过10%时,所提出的方法有很好的检测效果。
In the paper,a method of steganalysis is proposed for MIDI audio by LSB Matching based on the rate of smoothness——of which the orginal audio is different from the audio with hidden message. Hidden message would reduce the smoothness of stego MIDI audio. A conversion rate threshold value is picked up by training a set of MIDI audio for distinguishing whether a MIDI audio is Embedded. Experiments show that,when embedded rate is more than 10%,steganalysis in MIDI audio by the proposed method could be of high correct decision rate.