Les réponses impulsionnelles directionnelles: évaluation et application dans le cadre de l'acoustique des salles

Conference (2007)

Computation and applications of directional echograms in room and concert hall acoustics

Conference (2007)

A video-based human-computer interaction system for audio-visual immersion

in Proceedings of SPS-DARTS (2006, March)

This paper describes the video and audio tools that have been implemented in a real-type system to immerse a user into a virtual scene. The video tools include motion detection, skin detection by ... [more ▼]

This paper describes the video and audio tools that have been implemented in a real-type system to immerse a user into a virtual scene. The video tools include motion detection, skin detection by thresholding, shadow detection and extraction, and finally the user’s head and hands detection. Once this is done, the user (who is surrounded by a matrix of loudspeakers) is able to move a sound source in the horizontal plane around him. Moreover, the sound is auralized by convolution with (directional) room impulse responses, which have been pre-computed by a ray tracing method. The different sound contributions are distributed to the individual loudspeakers by applying the VBAP technique. [less ▲]

A tutorial on scattering and diffusion coefficients for room acoustic surfaces

in Acta Acustica United with Acustica (2006), 92(1, JAN-FEB), 1-15

There is a need to be able to quantify how sound is reflected from a surface, in terms of how it is spatially dispersed. In recent years, diffusion and scattering coefficients have been developed to ... [more ▼]

There is a need to be able to quantify how sound is reflected from a surface, in terms of how it is spatially dispersed. In recent years, diffusion and scattering coefficients have been developed to enable room acoustic prediction models to be more accurate, and designers to evaluate the worth of diffusing surfaces. Two coefficients have been, or are about to be, enshrined in standards. With two coefficients being standardised, there is great potential for confusion. This paper is intended to bring together authors from different areas to explain where the coefficients should and should not be applied. In addition, this tutorial paper will revisit the rationale behind the coefficients and contrast the coefficient definitions and performance. [less ▲]

3D real-time auralization with separate rendering of direct sound, reflections and directional late reverberation

in Proceedings of the 2006 international Conference on Auditory Display (2006)

Calculation of the random-incidence scattering coefficients of a sine-shaped surface

in Acta Acustica United with Acustica (2006), 92(4, JUL-AUG), 593-603

Random-incidence scattering coefficients obtained by measurement in reverberation chambers (ISO 17497-1) for a particular sine-shaped surface are compared with theoretical results. Holford-Urusovskii's ... [more ▼]

Random-incidence scattering coefficients obtained by measurement in reverberation chambers (ISO 17497-1) for a particular sine-shaped surface are compared with theoretical results. Holford-Urusovskii's method and a hybrid plane wave decomposition - FEM method are applied to an infinite sine-shaped surface having the same profile, while the 3D BEM gives numerical results for the finite-size surface. Perfect rigidity (Neumann boundary condition) is assumed in all computations. The validity of the computations is compared and discussed with regard to the approximations involved. Finally, the measured and calculated values of the scattering coefficients are compared. A good correspondence is found, in particular concerning the overall dependence on frequency. Small deviations have however been observed, at low as well as at high frequencies. They will be explained by uncertainties in the measurements and discretisation errors in the calculations. [less ▲]

Expériences de contrôle actif du bruit dans le bâtiment. Approches globales et locales.

Conference (2005)

Auralization in Room Acoustics using Directional Impulse Responses Computed by Sound Ray Techniques

in Proceedings of the 4th Forum Acusticum Congress (2005)

Active noise control in frontages of buildings

in Proceedings of SPS-DARTS 2005 (2005)

Signal and Image Exploitation at the University of Liège: Strategic Plan and Some Applications

Conference (2004)