Estimating the weight of evidence in forensic speaker verification
نویسندگان
چکیده
In forensic casework, the application of automatic speaker verification (SV) aims to determine the likelihood ratio of a suspect being vs. being not the speaker of an incriminating speech recording. For that purpose, the likelihood of the anti-speaker has to be estimated from the speech of an adequate number of other speakers. In many cases, speech signals of such an anti-speaker population are not available and it is generally too expensive to make an appropriate collection. This paper presents a practical procedure of forensic SV which is based on a text-dependent SV system and instead of an anti-speaker population, a special speech database is used to calibrate the valuation scale for an individual case.
منابع مشابه
A Bayesian network approach combining pitch and spectral envelope features to reduce channel mismatch in speaker verification and forensic speaker recognition
The aim of this paper is to reduce the effect of mismatch in recording conditions due to the transmission channel and recording device, using conditional dependencies of prosodic and spectral envelope features. The developed system is based on a Bayesian network framework which combines statistical models of the pitch and spectral envelope features. This approach is applied to forensic automati...
متن کاملBayesian calibration for forensic evidence reporting
We introduce a Bayesian solution for the problem in forensic speaker recognition, where there may be very little background material for estimating score calibration parameters. We work within the Bayesian paradigm of evidence reporting and develop a principled probabilistic treatment of the problem, which results in a Bayesian likelihood-ratio as the vehicle for reporting weight of evidence. W...
متن کاملUsing Exciting and Spectral Envelope Information and Matrix Quantization for Improvement of the Speaker Verification Systems
Speaker verification from talking a few words of sentences has many applications. Many methods as DTW, HMM, VQ and MQ can be used for speaker verification. We applied MQ for its precise, reliable and robust performance with computational simplicity. We also used pitch frequency and log gain contour for further improvement of the system performance.
متن کاملA Robust Framework for Forensic Speaker Verification
This paper discusses the application of automatic speaker verification systems in forensic casework. A framework for reporting the system outcome is proposed. Specific system requirements to properly cope with forensic idiosyncrasies are analyzed through a series of simulations. Results suggest that the design of a forensic speaker verification system not necessarily match the settings of curre...
متن کاملNoise robustness in forensic speaker verification
Recently, commercial speaker verification systems have been applied to forensic casework. Unfortunately, these systems were not custom tailored to current needs. In this paper we try to identify general guidelines towards establishing an improved forensic speaker verification methodology. A main issue is the recognition rate, which highly deteriorates in noisy conditions, preventing a reliable ...
متن کامل