不同手机及不同通信网络通话录音质量评析

Evaluation on Quality of Voices Recorded from Testing into Different Mobile Phones and Telecom Networks

目的为送检手机通话录音质量的审查提供理论依据。方法提出一种定量化的语音检材质量评价标准,并对不同手机及不同通信网络下的录音进行质量评价。该标准基于主流鉴定设备,涵盖了声学语谱图共振峰个数及数值、基频参数、区域平均频谱等分析方法以及声纹比对测试。结果实验结果显示,不同条件下得到的通话录音质量存在一定的差异性,会对声纹图谱鉴定产生一定影响,但并不会造成本质性差异。结论语音同一认定中,对基于移动通信网络获取的检材录音应考虑到通话语音质量的差异性对检验的影响,并在鉴定分析中加以评估和克服。

Objective To provide a theoretical basis for examination of mobile phone’s recording quality that is important for correct opinion to deliver in the forensic voiceprint identification of voice samples from the ubiquitous mobile phone calls.Methods A quantitative standard was proposed for evaluation of the recorded samples that were obtained from the tested mobile phones and generation-various telecom networks.The standard,rooting on the basis of mainstream identification equipment,was analyzed into the quantity and digital values of formant in voiceprint spectrogram,fundamental frequency parameters,regional average spectrum and implemented voiceprint comparison test.Results The test results showed that certain differences existed with the recording quality under different conditions,having caused definite influence on voiceprint identification,yet at a non-essential extent.Conclusion For voice identity authentication,the influence should be considered of recording quality differences on identification of the recorded samples from different mobile phones and telecom networks,therewith evaluated and overcome during identification.