小波突变点检测的扩频掩密分析算法

研究了音频信息隐藏技术中的"知彼"问题——掩密分析方法。该算法首先对含密音频进行小波去噪处理,然后进行滑动相关计算,最后利用小波突变点检测技术提取特征对待分析的音频进行分类,该算法检测性能具有只受秘密信息嵌入强度影响而与嵌入容量无关的特点。实验结果表明,含密音频中PN序列嵌入强度越大,检测的正确率越高。特别在嵌入强度只有0.002时,算法的检测正确率仍然达到了80%以上,因此,算法具有良好的检测性能。

A spread spectrum steganalysis algorithm based on discontinuity detection

A novel audio steganalysis method is proposed.. the audio signal is denoised with wavelet transform. Then, a part of noise signal with different length is intercepted circularly and is used to calculate the cross correlation sequence with the rest of the noise signal. With the wavelet discontinuity detection technique, the feature is extracted from the cross correlation sequence for steganalysis and find out the steg audio. The detection rate is determined by the embedding strength of the secret message other than the embedding capacity. Experimental results show that the more embedding intensity of PN sequence is, the higher the detection rate will be. The detection rate of the algorithm is above 80% when the strength of the PN sequence is about 0.002, which demonstrates that the proposed algorithm has good detection performance.