Binaural room scanning renderer

In the second example the BRS renderer will use BRIR recordings to simulate a source placed within a (reverberant) room. Again, the scene is defined via an XML-file, this time named brs_renderer.xml:

<?xml version="1.0" encoding="utf-8"?>
<scene
  Renderer="ssr_brs"
  BlockSize="4096"
  SampleRate="44100"
  LengthOfSimulation="5.0">
  <source Type="point"
          Name="SoundSource"
          IRs="impulse_responses/qu_kemar_rooms/auditorium3/QU_KEMAR_Auditorium3_src2_xs+4.30_ys+3.42.sofa">
    <buffer ChannelMapping="1"
        Type="noise"/>
  </source>
  <sink Name="Head"
        Position="0 0 0"
        UnitX="0 1 0"
        UnitZ="0 0 1"/>
</scene>

The renderer type is set to ssr_brs and the BRIR is specified within the <source> section. A source position is no longer required, as it is inherently given by the corresponding BRIR measurement. Note that the KEMAR dummy head was looking towards the y-axis during the BRIR measurement. In the scene description, the UnitX vector defines the looking direction of the virtual head; thus UnitX becomes [0 1 0]. The audio material used is synthesised by the simulator’s built-in white noise generator. That way, an infinitely long signal is generated, and the LengthOfSimulation property has to be specified. The following commands allow to listen to the final simulation; the perceptual impression should correspond to a noise source placed in a larger room to the front-right of the listener:

>> sim = simulator.SimulatorConvexRoom('brs_renderer.xml',1);
>> signal = sim.getSignal();
>> sound(signal, sim.SampleRate);

Here, the sim.set('Init', true) line has been omitted; the 1 used in simulator initialisation serves the same purpose.

If you are looking for complex acoustic scenes (e.g., moving around in a room or simulating moving sources), please have a look at the Examples section of the Binaural simulator.

[Horbach1999]Horbach, U., Karamustafaoglu, A., Pellegrini, R., Mackensen, P., Theile, G. (1999), “Design and Applications of a Data-based Auralization System for Surround Sound,” 106th AES Convention, Paper 4976
[Wierstorf2014]Wierstorf, H. (2014), “Perceptual Assessment of Sound Field Synthesis,” PhD-thesis, TU Berlin