Hybrid Models for Acoustic Reverberation Hequn Bai

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Hybrid Models for Acoustic Reverberation Hequn Bai Hybrid models for acoustic reverberation Hequn Bai To cite this version: Hequn Bai. Hybrid models for acoustic reverberation. Sound [cs.SD]. Télécom ParisTech, 2016. English. NNT : 2016ENST0009. tel-01677265 HAL Id: tel-01677265 https://pastel.archives-ouvertes.fr/tel-01677265 Submitted on 8 Jan 2018 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. 2016-ENST-0009 EDITE - ED 130 Doctorat ParisTech THÈSE pour obtenir le grade de docteur délivré par TELECOM ParisTech Spécialité « Signal et Images » présentée et soutenue publiquement par Hequn BAI le 8 février, 2016 Modèles Hybrides pour la Réverbération Sonore Directeur de thèse : Gaël RICHARD Co-encadrement de la thèse : Laurent DAUDET Jury T M. Sylvain MARCHAND, Professeur, Université de La Rochelle Rapporteur Mme. Rozenn NICOL, Chargé de Recherche, Orange Labs Rapporteur H M. Julien DE ROSNY, Professeur, Institut Langevin Président du jury È M. Lauri SAVIOJA, Professeur, Aalto University Examinateur M. Olivier WARUSFEL, Chargé de Recherche, IRCAM Examinateur S M. Nicolas TSINGOS, Directeur de Recherche, Dolby Laboratories Examinateur M. Gaël RICHARD, Professeur, Télécom ParisTech Directeur de thèse E M. Laurent DAUDET, Professeur, Université Paris Diderot Directeur de thèse TELECOM ParisTech école de l’Institut Mines-Télécom - membre de ParisTech 46 rue Barrault 75013 Paris - (+33) 1 45 81 77 77 - www.telecom-paristech.fr Modèles Hybrides pour la Réverbération Sonore Hequn BAI RESUME : Grâce au diverse applications prévues dans le divertissement, l’éducation et les domaines professionnels, la création d’un monde virtuel interactif a intéressé beaucoup de chercheurs dans l’académie et l’industrie. L’espace acoustique trois-dimensionnelle peut être synthétisé à partir de deux perspectives : les approches physiques et les approches perceptives. Méthode de transfert de rayonnement acoustique est une méthode efficace pour modéliser les réflexions diffuses et la réverbération tardive. Une extension de la méthode de transfert de rayonnement est proposée dans cette thèse, qui permet de modéliser les réflexions précoces et spéculaires, en conservant son avantage pour la simulation de réverbération tardive. Les approches perceptives utilisent des paramètres acoustiques pour modéliser la perception acoustique principale de l’environnement modélisé. Des réseaux récursifs de lignes à retard sont beaucoup utilisés pour générer de la réverbération tardive. Dans cette thèse, une nouvelle méthode est présentée, qui hérite l’effi- cacité de la structure des réseaux récursifs de lignes à retard, mais en le même temps, relie les paramètres des réseaux directement à la géométrie de l’environnement modélisé. Puis, l’approche physique et l’approche perceptive ont été combinées. La méthode de transfert de rayonnement acoustique simplifiée, avec extension à modéliser les réflexions spéculaires et diffuses, est incorporée à la structure des réseaux récursifs de lignes à retard. Le nouveau filtre réverbérant, en dépit de la modélisation des réfections diffuses et la réverbération tardive, est également capable de simuler les réflexions précoces et spéculaires avec précision. MOTS-CLEFS : acoustique des salle, reverberation, audio 3D, realité virtuelle ABSTRACT : There is an increasing interest in creating interactive virtual worlds due to the wide variety of potential applications in entertainment and education. The 3D acoustic scene can be synthesized from two perspectives : the physical approaches and the perceptual ap- proaches. Acoustic radiance transfer method is an efficient ray-based method to model the diffusereflections and the late reverberation. An extension of the Radiance Transfer Method (RTM) is proposed in this thesis, which allows modeling the early part of specular reflections while keeping the advantage of the original model for the late reverberation simulation. Feedback delay networks are widely used structures to generate the late reverberation. A new method is presented in this thesis, which inherits the efficiency of the Feedback Delay Net- work (FDN) structure, but aims at linking the parameters of the FDN directly to the geometries of the modeled environment. The relation is achieved by assigning a physical meaning to each delay line and studying the sound energy exchange between them. Then the physical approach and the perceptual approach are combined. The simplified acoustic Radiance Transfer Method, with extension for both specular and diffuse reflections, is incorporated with the Feedback Delay Networks. The new reverberator, despite of modeling the diffuse and late reverberation, is also capable of simulating the early and specular reflections with accuracy. KEY-WORDS : room acoustics, reverberation, 3D audio, virtual reality. RÉSUMÉ iii Résumé Grâce au diverse applications prévues dans le divertissement, l’éducation et les domaines pro- fessionnels, la création d’un monde virtuel interactif a intéressé beaucoup de chercheurs dans l’académie et l’industrie. Dans ces scenarios d’applications, il est particulièrement important d’avoir des outils puissants et ecaces pour la synthèse de l’audio trois-dimensionnel pour créer des espaces acoustiques dynamiquement à partir de la géométrie virtuelle de l’espace. Un tel système qui synthèse la propagation du son dépend de la géométrie de l’espace simulée, de la présence d’obstacles dans l’espace et de la position des sources sonores et des récepteurs. Pen- dent des dernières vingt années, de nombreuses études ont été menées dans le domaine de la simulation de la propagation du son dans les environnements complexes. L’espace acoustique trois-dimensionnelle peut être synthétisé à partir de deux perspectives : les approches physiques et les approches perceptives. Les approches physiques considèrent le problème de la modélisation de la propagation du son précis dans l’environnement pour toutes les fréquences audibles par l’oreille d’humaine. Méthode de transfert de rayonnement acoustique est une méthode ecace pour modéliser les réexions diuses et la réverbération tardive. Une extension de la méthodede transfert derayonnement est proposéedans cettethèse, quipermetde modéliser les réexions précoces et spéculaires, en conservant son avantage pour la simulation de réverbération tardive. Les réexions entre les murs sont pré-calculées et découplés de la course de calcul. Lorsque le caractéristiques et les locations de la source et le récepteur changent, que l’état initial et nal doivent être ré-calculés et mis à jour. Cela réduit le calcul pour les scènes dynamiques. Les approchesperceptives, par contre, utilisent des paramètresacoustiques, comme le tempsde réverbération, pour modéliser la perception acoustique principale de l’environnement modélisé. A cause de l’ecacité de calcul, des réseaux récursifs de lignes à retard sont beaucoup utilisés pour générer de la réverbération tardive. Dans cette thèse, une nouvelle méthode est présentée, qui hérite l’ecacité de la structure des réseaux récursifs de lignes à retard, mais en le même temps, relie les paramètres des réseaux directement à la géométrie de l’environnement modélisé. La relation est obtenue par étudier la signication physique de chaque ligne à retard et attribuer de l’échange de l’énergie acoustique entre les murs à chaque ligne. Puis, dans la dernière partie de cette thèse, l’approche physique et l’approche perceptive ont été combinées. La méthode de transfert de rayonnement acoustique simpliée, avec extension à iv RÉSUMÉ modéliser les réexions spéculaires et diuses, est incorporée à la structure des réseaux récur- sifs de lignes à retard. Le nouveau ltre réverbérant, en dépit de la modélisation des réfections diuses et la réverbération tardive, est également capable de simuler les réexions précoces et spéculaires avec précision. La matrice récursive dénit les réexions spéculaires entre com- posants de la géométrie. Car les réexions entre les composants de la géométrie ont été décou- plées de la course de calcul, seulement l’état initial et nal doivent à être mis à jour lorsque la source / récepteur se déplace. Ainsi, ce ltre réverbérant est approprié pour des applications dans les scènes dynamiques. Mots-clé: L’Eet acoustique de salle réverbération, le temps de réverbération, transfert de rayonnement acoustique, réseau récursif de lignes à retard, réalité virtuelle, audio trois-dimensionnel, ltre réverbérant. ABSTRACT v Abstract There is an increasing interest in creating interactive virtual worlds due to the wide variety of potential applications in entertainment and education. In these applications, creating dynamic 3D acoustic scenes from a given 3D graphical set up is of particular importance. The 3D acoustic scene can be synthesized from two perspectives: the physical approaches and the perceptual approaches. The physical approaches model the accurate sound propagation in the acoustic environment using the wave-based methods or the ray-based methods. Acoustic radiance transfer method is an ecient ray-based method to model the diuse reections and the late reverberation. An extension of the Radiance
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