Article
Computationally Efficient and Spatially Smooth Edge Diffraction for Virtual Acoustics (en)
* Presenting author
Abstract:
Virtual acoustics can be used to create complex acoustic environments with applications in, e.g., hearing research, architectural planning and entertainment. Due to the high demands regarding computational efficiency, dynamic real-time renderings are usually based on geometrical acoustics (GA), assuming ray-like sound propagation. However, in real sound fields, diffraction leads to perceptually relevant effects, particularly when sound sources become occluded. To approximate diffraction in the framework of GA, additional diffraction paths are modeled and superimposed with the geometrical direct sound and specular reflections (image sources). In addition to establishing the diffracted paths, an accurate, fast, and spatially smooth modelling of the spectral and temporal effects of diffraction is still a challenge.Here, a computationally highly efficient, scalable infinite-impulse response (IIR) filter approach to account for spectral effects of diffraction is shown. Strategies are presented to achieve a smooth transition between a visible and occluded sound source by i) a room corner and ii) a flat plate. For the latter case, our diffraction simulations are compared to reference measurements in anechoic chamber with a source and receiver trajectory passing both the shadow and reflection boundaries.