Prediction and measurement of the random incidence scattering coefficient of periodic reflective rectangular diffuser profiles

in Proceedings of the 2013 ICA Congress (2013, June)

Efficient database pruning for large-scale cover song recognition

in International Conference on Acoustics, Speech, and Signal Processing (ICASSP) (2013, May)

This paper focuses on cover song recognition over a large dataset, potentially containing millions of songs. At this time, the problem of cover song recognition is still challenging and only few methods ... [more ▼]

This paper focuses on cover song recognition over a large dataset, potentially containing millions of songs. At this time, the problem of cover song recognition is still challenging and only few methods have been proposed on large scale databases. We present an efficient method for quickly extracting a small subset from a large database in which a correspondence to an audio query should be found. We make use of fast rejectors based on independent audio features. Our method mixes independent rejectors together to build composite ones. We evaluate our system with the Million Song Dataset and we present composite rejectors offering a good trade-off between the percentage of pruning and the percentage of loss. [less ▲]

Sound for 3D Cinema and the Sense of Presence

in Nees, Michael A.; Walker, Bruce N.; Freeman, Jason (Eds.) Proceedings of the 18th International Conference on Auditory Display (2012, June 18)

While 3D cinema is becoming more and more established, little effort has focused on the general problem of producing a 3D sound scene spatially coherent with the visual content of a stereoscopic-3D (s-3D ... [more ▼]

While 3D cinema is becoming more and more established, little effort has focused on the general problem of producing a 3D sound scene spatially coherent with the visual content of a stereoscopic-3D (s-3D) movie. As 3D cinema aims at providing the spectator with a strong im- pression of being part of the movie (sense of presence), the perceptual relevance of such spatial audiovisual coherence is of significant interest. Previous research has shown that the addition of stereoscopic informa- tion to a movie increases the sense of presence reported by the spectator. In this paper, a coherent spatial sound rendering is added to an s-3D movie and its impact on the reported sense of presence is investigated. A short clip of an existing movie is presented with three different sound- tracks. These soundtracks differ by their spatial rendering quality, from stereo (low spatial coherence) to Wave Field Synthesis (WFS, high spatial coherence). The original stereo version serves as a reference. Results show that the sound condition does not impact on the sense of presence of all participants. However, participants can be classified according to three different levels of presence sensitivity with the sound condition impacting only on the highest level (12 out of 33 participants). Within this group, the spatially coherent soundtrack provides a lower reported sense of presence than the other custom soundtrack. The analysis of the participants’ heart rate variability (HRV) shows that the frequency-domain parameters correlate to the reported presence scores. [less ▲]

Evaluation of the acoustic comfort of air-treatment systems with a multi-task procedure

in E.A.A. (Ed.) Proceedings of the 2012 Euronoise Congress (2012, June)

Timbre description of the sound of air-treatment systems for predicting acoustic confort

Poster (2012, April)

Ray-tracing modelling of the diffraction by half-planes and slits based on the energy flow lines concept

in Proceedings of the Acoustics 2012 Nantes conference (2012, April)

Searching for a theoretical relation between reverberation and the scattering coefficients of surface in a room

in Proceedings of the Acoustics 2012 Nantes conference (2012, April)

Microphone arrays fundamentals

Conference (2011, November 23)

Microphone arrays are essentially directional sensors. They are therefore mainly used for locating, identifying, isolating, measuring and recording individual sound sources. The main principles governing ... [more ▼]

Microphone arrays are essentially directional sensors. They are therefore mainly used for locating, identifying, isolating, measuring and recording individual sound sources. The main principles governing the directivity of microphone arrays are reviewed: phase differences between signals create constructive and destructive interferences, depending on the direction of the sound source. Moreover, signal processing is applied to provide “beamforming”, i.e. beam shaping and steering. Contrary to continuous antenna, discrete arrays can create aliasing, which can result in false detections of sound sources. The delay-and-sum and filter-and-sum beamformers are described. Finally, as simple beamformers are often frequency dependent, some solutions to obtain constant (broad-band) directivity are presented. [less ▲]

Numerical evidence of mixing in rooms using the free path temporal distribution

in Journal of the Acoustical Society of America (2011), 130(3), 13811389

The ergodic propriety of a room has strong effects on its reverberation. If the room is ergodic, the reverberation can be broken up in two steps: a deterministic process followed by a stochastic one. The ... [more ▼]

The ergodic propriety of a room has strong effects on its reverberation. If the room is ergodic, the reverberation can be broken up in two steps: a deterministic process followed by a stochastic one. The late reverberation can be then modeled by a reverberation algorithm instead of more computationally consuming methods. In this study, the free path temporal distribution obtained by ray-tracing is used as an indicator of the room’s mixing: the energetic average of the path lengths is computed at each time step. Ergodic rooms are thus characterized by rapidly convergent distributions. The free path value becomes independent of time. On the other hand, path selection mechanism and orbits are observed in non-ergodic rooms. The transition time from the deterministic process to the stochastic one is also studied through the evaluation of the room’s time constant. It is shown that its value depends only on the mean free path and the boundaries scattering value. An empirical expression is obtained which agrees well with simulations carried out in a concert hall. This transition time from a deterministic model to a stochastic one can be used to speed up the acoustical predictions and auralizations in ergodic rooms. [less ▲]

Acoustic comfort of air-treatment systems: influence of factors related to room acoustics

Conference (2011, June 30)