Voiceprint Recognition Technology And It's Application In Forensic Expertise

Voiceprint recognition technology is the process of recognizing who is speaking based on individual information which included in speech signals. This paper studied the use of voiceprint recognition technology in the field of forensic expertise.The demands of expertise for voice evidence are expanding, with the reform in judicial system and the rapid development of electronic and communications technology. Currently, voiceprint recognition in large domestic forensic bodies is also depended on advanced equipments from abroad. But this kind of equipments is very expensive. This research aims to develop a low-cost system which also could meet the requirements of the voiceprint recognition, in order to adapt to the situation of shortage of funds in more and more medium-sized forensic institutions.To meet the demands of forensic expertise for voice evidence, this paper introduced the process of voiceprint recognition in forensic expertise briefly. And it also explained the methods of voice signal's sampling and quantization. Then extract some parameters, such as LPC, LPCC, MFCC and so on, which could reflect the physical of behavioral characteristics of the speaker. Focus on using the spectrogram to recognize. This paper completed the sampling, quantization and preprocessing of the voice signals, and extract characteristic parameters and map spectrogram by MATLAB 6.5. Besides, it also did some further analysis and verification on voice samples recorded by ourselves. Finally, there is an actual cases of voiceprint recognition in forensic expertise.