SOURCE LOCALIZATION BY VIRTUAL ACOUSTIC REALITY

Abstract

This thesis presents a new algorithm for virtual sound source positioning for the purposes of rendering acoustic components of headphone-based virtual reality. The one-channel positioning method using Di erential Head-Related Transfer Function (DHRTF) is introduced. The DHRTF method utilizes localization cues (time and intensity di erences) extracted from HRTF pairs for particular positions. In contrast to the usual two-channel ltering by a HRTF pair, only one channel is processed when the DHRTF algorithm is applied. This results in one channel is being delayed and attenuated with respect to the other one, which contains the unprocessed original sound. Therefore, the nal positioned sound has the same time and level di erences as when ltered by the HRTF pair, however, with di erent signals in each channel. An introduction to the eld of virtual positioning and contemporary state-of-the-art presents the rst chapter. The theoretical concept of the DHRTF positioning method is presented and demonstrated with model examples in the second chapter. Speci c features, performance, and e ciency of the DHRTF algorithm are examined and compared to the attributes of other positioning methods (namely amplitude panning and HRTF ltering) in the last chapter. The highlights of the results delineate remarkably good spatial depth, reduction of processing requirements, and low a ection of natural sound timbre. Possible applications of the DHRTF method are in assistive systems for visually impaired, in computer games audio, and in enhancing spatialization of musical or lm mixing on digital audio workstations.