Steganographic method in self-adaptive codebooks of speech codec
Yongfeng Huang · Jisuanji gongcheng yu sheji · 2013
In order to solve information hiding problem in low bit rate speech coding,taking the low bit rate speech coding as the steganographic carrier and the widely used iLBC as the research subject,a kind of information hiding method is proposed by which confidential information is embedded within the speech coding process,and then a steganographic algorithm is designed which is based on the quantization process of the dynamic codebook of iLBC speech codes.Information hiding is initiatively achieved via QIM axiom by utilizing the property of dynamic composing of the self-adaptive codebooks of the low bit rate speech coding.Tests show that the method is of higher deficiency concerning the anti-testing of statistical analysis and has a better performance in imperceptibility compared with the traditional QIM method which is based on static codebook.According to the relative experiments,up to 450 bps steganographic capacity is achieved within 13.3 Kbps carrier rate while the loss of PESQ value of speech quality with steganographic information is less than 7%,which shows a superb performance of imperceptibility.