The Use of Time-Scale Analysis in Forensic Acoustical Investigations

The identification and characterization of noise events is one of the most important task in acousticalforensic analysis. In this field it is often fundamental to distinguish, within a complex acoustical framework, thedifferent noise events, especially because, in many cases, the operator cannot be present at the measurements. Itis fundamental to be able to distinguish the atypical or extraneous noise events from the specific ones underinvestigation and know what type of sources make up the noise climate. To this aim is essential to develop a time- frequency analysis technique able to overcame the known limitations of the “traditional” 1/3 of octave frequencyanalyses. In this paper a novel technique, based on multiresolution analysis, has been developed and applied tosome forensic “typical” problems, showing that a suitable choice of the analysis parameters can be able to answerto the main questions of this field