Individual Binaural Synthesis of Virtual Acoustic Scenes

• Applicants: Professorin Dr.-Ing. Janina Fels; Professor Dr.-Ing. Sascha Spors
• Subject Area: Acoustics
• Term: from 2018 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 402811912

• Final Report Year: 2024

Final Report Abstract

In recent years, virtual reality has found its way into many areas. The focus of the major technical developments has traditionally been layed on the visual representation. However, a convincing auditory representation is also necessary for a high-quality virtual reality. Various methods are available for headphone-based generation of acoustic virtual reality. In model-based binaural synthesis, Head-Related Transfer Functions (HRTFs) are used to auralize individual virtual sources. Data-based binaural synthesis uses microphone arrays together with audio signal processing and HRTFs. Generic HRTFs from dummy heads can lead to problems with in-head localization, front-back confusion and sound coloration in both approaches. There are numerous methods for fast measurement of individual HRTFs, as well as algorithms for individualizing generic HRTFs. For the former, however, there was a lack of systematic validation of the measurement uncertainties due to the measuring apparatus and the influence of the subject's movement. The same applied to the validation of algorithms for the individualization of generic HRTFs. The effects of measurement uncertainties and approximations in the algorithms of model and data-based binaural synthesis on the authenticity and plausibility of acoustic scenes were the research subject of this project. A key question here was to what extent an improvement of a presented virtual acoustic scene can be achieved with the help of individualized or individually measured HRTFs compared to generic HRTFs. In addition to instrumental measures, empirical studies in the form of listening experiments were used for evaluation.

Publications

• “Investigating Uncertainties in Fast HRTF Measurements,” in Proceedings 23rd ICA, Aachen, Germany, 2019, p. 5211
  S. Doma, H. Braren & J. Fels
  
• “On the detection quality of early room reflection directions using compressive sensing on rigid spherical microphone array data”. In: Proc. 23rd Intl Congress of Acoustics, Aachen. 2019, S. 2676–2683.
  F. Schultz & S. Spors
  
• “Effect of subject misalignment during HRTF measurements on spatial acoustic resonances,” in Fortschritte der Akustik – 46. DAGA, Hannover, 2020
  S. Doma & J. Fels
  
• “Analysis of spatial cue distortion in HRTFs using a simplified head model,” in Fortschritte der Akustik – 47. DAGA, Wien, 2021
  S. Doma & J. Fels
  
• “Examining the influence of controlled HRTF-variation on various distance metrics,” in Fortschritte der Akustik – 47. DAGA, Wien, 2021
  C. A. Ermert, S. Doma & J. Fels
  
• Hybrid multi-harmonic model for the prediction of interaural time differences in individual behind-the-ear hearing-aid-related transfer functions. Acta Acustica, 6, 34.
  Pausch, Florian; Doma, Shaima’a. & Fels, Janina
  
• Interrelation Analysis of Distance Metrics for Head-Related Transfer Functions,” in Fortschritte der Akustik – 48. DAGA, Stuttgart, 2022 (Poster)
  S. Doma, N. Brozova & J. Fels
  
• “A Closer Look On Linearly and Quadratically Constrained Least-Squares Binaural Decoder Performance Using Individualised HRTFs”. In: Proc. 48th DAGA, Stuttgart, 2022, S. 1413–1415.
  F. Schultz, S. Doma, J. Fels & S. Spors
  
• A Magnitude-Based Parametric Model Predicting the Audibility of HRTF Variation. Journal of the Audio Engineering Society, 71(4), 155-172.
  Doma, Shaimaa; Ermert, Cosima A. & Fels, Janina
  
• Examining the interrelation behavior of distance metrics for head-related transfer function evaluation: a case study. Acta Acustica, 7, 34.
  Doma, Shaima’a.; Brožová, Natálie & Fels, Janina
  
• HRTF Individualised Mag-LS and COMPASS Ambisonics-To-Binaural Rendering: Overall Perceived Quality for Pre-Conditioned Listeners,” in Audio Eng. Soc. Convention 154, Espoo, Helsinki, Finnland, Mai 2023 (open-access)
  F. Schultz, S. Doma, S. Spors & J. Fels
  
• “Examining the minimum detectable bi-lateral variation of generic Head-Related Transfer Functions,” Audio Eng. Soc. Convention 154, Espoo, Helsinki, Finnland, Mai 2023 (open-access)
  S. Doma & J. Fels
  
• “HRTF Individualised Mag-LS and COMPASS Ambisonics-To-Binaural Rendering: Overall Perceived Quality for Pre-Conditioned Listeners”. In: Proc. of 154th Audio Eng. Soc. Conv., Espoo, 2023.
  F. Schultz, S. Doma, S. Spors & J. Fels
  
• “On the monaural contribution to HRTF discrimination,” in Fortschritte der Akustik – 49. DAGA, Hamburg, 2023.
  S. Doma, C. A. Ermert & J. Fels
  
• “Towards a data-driven plane wave decomposition from multichannel room impulse responses”. In: Proc. 49th DAGA, Hamburg, 2023, S. 1671–1674.
  D. Schindler, F. Schultz & S. Spors
  
• HRTF Individualised Ambisonics-To-Binaural Rendering Using Mag-LS and Compass: A Perceptual Evaluation of Overall Quality. Proceedings of the 10th Convention of the European Acoustics Association Forum Acusticum 2023, 2713-2716. European Acoustics Association.
  Schultz, F.; Doma, S.; Spors, S. & Fels, J.