Présentation d'un système d'auralisation reproduisant de manière fidèle toutes les caractéristiques spatiales

M = 26 solid angles (directional microphones) 67 5 22 5 0 -67 5 -22 5.

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is the RIR associated to a very small solid angle dΩ

including the direction of interest and evaluated at the listener location

For headphones auralization the sound contribution coming from a given direction of incidence (first reflections) or from a given solid angle (other contributions) must be convolved with the corresponding HRTF

Ray tracing Software

Phase is recreated for every direction during the conversion Comparison between echogram and recontructed echogram for IR : Statistical errors :

Comparison for several Directional resolutions 0 1 2 3 4 5 6 −2 0 2 4 6 8 10 12 temps(sec.) Erreur(dB)

Erreurs satistiques: noir = sphere omni, bleu = 26 angles, vert = 6 angles

VBAP Panning law is used

One impulse response is obtained for each audio channel Directional Room Impulse Response Directional echogram

CINEMA research project is supported by the Walloon Regional Government of Belgium under contract n° RW-021/5392

It is interesting for some particular virtual spaces, to reproduce the effects of directional RIRs, not only for the first-orders mirror sources, but also for the whole echogram.

This technique is mostly useful in spaces where diffusion is not predominant, and particularly at low and medium frequencies.

−2−1.5 −1−0.50 0.51 1.5 00.5 11.5 2 2.53 3.54 4.5 0 0.5 1 1.5 2 2.5 Y Audiometrie X Z 5 10 15 30 210 60 240 90 270 120 300 150 330 180 0

RoomB , T30 directionnel (Plan Horiz.) pour la Sphere no : 1, Freq : 62.5Hz

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Instead of traditional spatial parameters (for example IACC or Lateral fraction), we suggest the use of directional parameters such as Tr30Dir, E80Dir or E160Dir.

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- Real-time partitioned convolution(low latency)

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- Output on soundcard (alsa driver)

- Interactivity (GUI, head-tracker, mouse, keyboard)

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For example, in case of headphones:

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