Due to the covid-19 pandemic, companies and schools had to online go for meetings. With the opening of countries, people can now choose to attend meetings both physically and remotely which has led to the evolution of hybrid meetings. This thesis project focuses on how the perceived presence could be enhanced for remote participants. The purpose of the research is to explore the technology of dynamic binaural audio in the context of hybrid meetings and what the effects are on the remote participants.The paper presents the results through observations and interviews with the case study group, in combination with different literature studies. With the findings, a prototype for dynamic binaural audio has been developed and user-tested. As result, the remote participants reported a higher perceived presence with the implementation of dynamic binaural audio. Although, the implementation of dynamic binaural audio together with a static two dimensional video left some remote participants with a lower perceived presence due to asynchrony.

Recent advancements in audio technology for computer games has made possible for implementations with binaural audio. Compared to regular stereo sound, binaural audio offers possibilities for a player to experience spatial sound, including sounds along the vertical plane, using their own headphones. A computer game prototype called “Crystal Gatherer” was created for this study to explore the possibilities of binaural audio imple- mentation regarding localization and perception of objects that make sound in a 3D game. The game featured two similar game levels, with the difference that one used binaural sound, and the other stereo sound. The levels consisted of a dark space that the player could navigate freely with the objective to find objects that make sound, called “crystals”, as fast as they could. An experiment was conducted with 14 test sub- jects that played the game, qualitative and quantitative data was collected, including the time the players took to complete the game levels, respectively, and answers about how they experienced the levels. A majority of test subjects reported that they per- ceived a difference between the levels. No significant difference was found between the levels in terms of efficacy of finding the objects that made sound. Some test subjects stated that they found localization was better in the binaural level of the game, others found the stereo level to be better in this respect. The study shows that there can exist possibilities for binaural audio to change the perception of audio in computer games.

This paper explores how vision affects spatial audio perception in virtual reality. We created four virtual environments with different reverb and room sizes, and recorded binaural clicks in each one. We conducted two experiments: one where participants judged the audio-visual match, and another where they pointed to the click direction. We found that vision influences spatial audio perception and that congruent audio-visual cues improve accuracy. We suggest some implications for virtual reality design and evaluation.

This thesis analyses if the change of auditory feedback can improve the effectiveness of performance in the interaction with a non-visual system, or with a system used by individuals with visual impairment. Two prototypes were developed, one with binaural audio and the other with stereo audio. The interaction was evaluated in an experiment where 22 participants, divided into two groups, performed a number of interaction tasks. A post-interview were conducted together with the experiment. The result of the experiment displayed that there were no great difference between binaural audio and stereo regarding the speed and accuracy of the interaction. The post-interviews displayed interesting differences in the way participants visualized the virtual environment that affected the interaction. This opened up interesting questions for future studies.

De nombreuses études ont été menées lors des vingt dernières années dans le domaine de l’auralisation.Elles consistent à rendre audible les résultats d’une simulation acoustique. Ces études se sont majoritairementfocalisées sur les algorithmes de propagation et la restitution du champ acoustique dans desenvironnements complexes. Actuellement, de nombreux travaux portent sur le rendu sonore en tempsréel.Cette thèse aborde la problématique du rendu sonore dynamique d’environnements complexes selonquatre axes : la propagation des ondes sonores, le traitement du signal, la perception spatiale du son etl’optimisation informatique. Dans le domaine de la propagation, une méthode permettant d’analyser lavariété des algorithmes présents dans la bibliographie est proposée. A partir de cette méthode d’analyse,deux algorithmes dédiés à la restitution en temps réel des champs spéculaires et diffus ont été extraits.Dans le domaine du traitement du signal, la restitution est réalisée à l’aide d’un algorithme optimisé despatialisation binaurale pour les chemins spéculaires les plus significatifs et un algorithme de convolutionsur carte graphique pour la restitution du champ diffus. Les chemins les plus significatifs sont extraitsgrace à un modèle perceptif basé sur le masquage temporel et spatial des contributions spéculaires.Finalement, l’implémentation de ces algorithmes sur des architectures parallèles récentes en prenant encompte les nouvelles architectures multi-coeurs et les nouvelles cartes graphiques est présenté. / During the past twenty years many studies have been conducted in the field of auralization, which aimsat rendering audible the results of an acoustic simulation. These studies have mainly focused on thepropagation algorithms and the sound field audio rendering for complex environments. Currently, muchresearch concentrates on real-time audio rendering.This thesis addresses the problematic of real-time audio rendering of complex environments accordingto four axes: sound propagation, Digital Signal Processing (DSP), spatial perception of sound andcomputational optimizations. In the field of propagation, a method that aims at analyzing the varietyof existing algorithms is proposed. This method yields two algorithms dedicated to the real-time propagationof both specular and diffuse information. In the field of DSP, the auralization is performed withan efficient binaural spatialization module for the most significant specular information, and a GPUconvolution algorithm for the diffuse sound field auralization. The most significant paths are extractedthanks to a perceptive model based on temporal and spatial masking of the specular contributions.Finally, the implementation of these algorithms on recent computer architectures, taking advantage ofthe parallel processing of the new CPUs, and the benefits of GPUs for DSP calculations is presented.