Forschungtiny-AVE
The virtual environments which are created, e.g., in current computer games, focus to a large extend on the visual modality. A great effort is made to achieve plausible and yet impressive visual effects. The generation of plausible and yet impressive aural effects can further enhance the user's quality of experience. Just as graphic artists design a visual environment to stimulate certain emotions, a sound designer or "aural architect" can do the same acoustically. Deriving an acoustical model only from the geometry data which was used to create the visual environment limits the aural architect's scope for design. For entertainment purposes, an auralization software which offers more freedom for the design is more appropriate than a physically accurate acoustical simulation. Our latest auralization software, "tinyAVE", focuses on the generation of artistic and yet natural sounding reverberation (Borß and Martin, 2009; Borß, 2009).
"tinyAVE" uses the room geometry, the frequency dependent reverberation time, and the echo density profile as design parameters and is constructed from three signal processing blocks. The first block renders the direct sound and the early reflections and takes the most prominent geometry and position dependent cues into account using an efficient resampling approach for simulating Doppler effects with low signal distortion (Borß, 2008). The second block simulates higher-order specular reflections without taking the actual positions of the listener and the sound sources into account. The third block adds diffuse late reverberation.
The following examples were rendered with "tinyAVE" using anechoic classical music recorded by Tapio Lokki, Jukka Pätynen, and Ville Pulkki at the Helsinki University of Technology in Finnland (Pätynen, Pulkki, and Lokki, 2008). Two synthetic rooms of different size (912 m³ and 7299 m³) and reverberation times (T60 = 1.4 sec and T60 = 1.8 sec) were used as virtual concert halls. For both rooms, we have auralized the concert for three listening positions (conductor, loge, and backseat of the auditorium). The examples are available as "AC-3" files for a 5.1 surround system and as "MP3" files for headphones.
Small concert hall (T60 = 1.4 sec):
| Format | Position: Conductor |
Position: Loge |
Position: Backseat |
|---|---|---|---|
| MP3 (Headphones) |
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| AC-3 (Multi-Speaker) |
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Large concert hall (T60 = 1.8 sec):
| Format | Position: Conductor |
Position: Loge |
Position: Backseat |
|---|---|---|---|
| MP3 (Headphones) |
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| AC-3 (Multi-Speaker) |
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Further audio examples rendered with "tinyAVE" can be found on the homepage of the HearCom and the HybridReverb project.
References
Borß, C., Martin, R. (2009). "An Improved Parametric Model for Perception-Based Design of Virtual Acoustics", in AES 35th Int. Conference, London, UK, Feb. 2009.
Borß, C. (2009). " A Novel Approach for Optimally Matching a Late Reverberation Model to an Image Source Model - Or: What Does a Football Have to Do With Shoebox Shaped Rooms?", in Proc. Auralization Symposium of the European Acoustics Association, Espoo, Finland, Jun. 2009.
Borß, C. (2008). "Effcient Asynchronous Resampling of Audio Signals for Spatial Rendering of Mirror Image Sources", Proc. Annual Meeting of the German Acoust. Society , DAGA, Dresden (Germany), Mar. 2008.
Pätynen, J., Pulkki, V., and Lokki, T. (2008). "Anechoic Recording System for Symphony Orchestra", Acta Acustica united with Acustica, vol. 94, nr. 6, pp. 856-865, Nov./Dec. 2008.