On the improvement of accommodation to non-individual HRTFs via VR active learning and inclusion of a 3D room response

Abstract

This study examines the efficiency of a training protocol using a virtual reality application designed to accelerate individual’s selection of, and accommodation to, non-individualized HRTF profiles. This training introduces three elements to hasten audio localization performance improvement: an interactive HRTF selection method, a parametric training program based on active learning, and a relatively dry room acoustic simulation designed to increase the quantity of spatial cues presented. Participants rapidly selected an HRTF (≈5 min) followed by training over three sessions of 12 min distributed over 5 days. To study the impact of the room acoustic component on localization performance evolution, participants were divided into two groups: one acting as control reference, training with only anechoic renderings, the other training in reverberant conditions. The efficiency of the training program was assessed across groups and the entire protocol was assessed through direct comparisons with results reported in previous studies. Results indicate that the proposed training program led to improved learning rates compared to that of previous studies, and that the included room response accelerated the learning process.

Perceptual Impact on Localization Quality Evaluations of Common Pre-Processing for Non-Individual Head-Related Transfer Functions

“…While the evaluation of similarity between HRTF assessments across the full rating scale is appropriate for investigating the effect of post-processing modifications on the perceived spatial quality of HRTFs, it is also informative to focus on specific ranges in the rating scale. Admittedly most evaluation/selection protocols focus on the identification of the "best-rated" HRTFs, disregarding "mediocre" or "unfit" data [46,47,36,11]. Additionally the use of a coarser rating scale has been shown to boost similarity in HRTF assessments [31].…”

“…Nevertheless, even for cases when personalized HRTFs are available, they are hardly ever used without any type of processing. Whether performed to ensure compatibility between datasets from different databases [8], reduce the complexity in high-resolution HRTF spectra to perceptually relevant information [9] and lower the high dimensionality of the data [10], or be used in VR applications [11] and/or over the Web [12], HRTF post-processing is a reality that alters some aspects of the original measured data. Most often, while such actions affect the frequency and phase spectra of the data in a destructive manner, they are designed to constrain such artifacts to be within levels that are considered "acceptable" based on past research.…”

System-to-User and User-to-System Adaptations in Binaural Audio

“…It has been established that one can adapt to modified HRTFs over time, with ear moulds inserted in the pinnae [19,38,94,95], or with non-individual HRTFs through binaural rendering [73,77,90,92,99,109]. Studies have shown that one can adapt to distorted HRTFs, e.g.…”

“…HRTF learning is not only possible, but lasting in time [62,92,109]: users have been shown to retain performance improvements up to 4 months after training [109]. Given enough time, participants using non-individual HRTFs may achieve localisation performance on par with participants using their own individual HRTFs [73,77,92].…”

Spatial Knowledge via Auditory Information for Blind Individuals: Spatial Cognition Studies and the Use of Audio-VR

“…Through such simulations, and subsequent "auralization" of the simulated room acoustic, it is then possible to render audible the acoustics of a computer simulated space [53,54]. While employed in the acoustic design of buildings [55,56], the auralization of simulated room acoustics is also at the centre of high quality virtual reality simulations which have been used, in, e.g., multimodal perception research [57,58] and historical reconstructions [59][60][61]. These techniques of binaural audio and room acoustic auralization are employed in several of the studies presented here.…”