VSpace

Summary

  • Description: Auralization Software. The acoustic space is miked up with any number of virtual microphones of various types. With a scripting language space, microphones and moving sounds can be described. Off-line rendering only.
  • Manufacturer / Developer: Richard Furse
  • Version: described version
  • Platform: stand-alone application, forming part of MNLib, a set of C++ libraries and programs for audio processing
  • OS: Linux, MacOS, Windows
  • License: Copyright 1999-2000 Richard W.E. Furse (all rights reserved)
  • etc....
  • Status of this entry: in progress

Parameter definition

VSpace has its own script language

Coordinate system convention

  • Three-dimensional right-handed cartesian coordinate system
    o positive X is forwards, negative X is backwards
    o positive Y is to the left, negative Y is to the right
    o positive Z is upwards, negative Z is downward
  • By default the distance unit is meters, can be changed

Parameter describing a sound source

  • Sound sources that may move in linear and circular motion. Sound sources may be directional.
parameter description data format range initial state unit example misc
distance unit set distance unit, used for all distances in the program string metre / foot / yard metre - distance unit metre;
sourceParameter4 .. .. .. .. unit .. ..
sourceParameter5 .. .. .. .. unit .. ..
sourceParameter6 .. .. .. .. unit .. ..

Parameter describing a virtual space

  • The space is assumed to be a box shape with the origin within the box and with the walls of the box parallel to the three axes.
  • Doppler shift induced using accurate model (moving write head delay lines and careful volume shading).
parameter description data format range initial state unit example misc
early reflection time .. float ? 0.25 seconds early reflection time 0.6; After the early reflection time the late reflection engine takes over. (can be disabled)
early reflection minimum gain cuts out faint early reflections to save CPU. float 0 .. 1 0.001 linear gain early reflection minimum gain 0.005; Higher values cut out more early reflections
disable early reflections disables the early reflection engine none none ? none disable early reflections; ..
late reflection cutoff sets the cuttoff frequency of a lowpass filter used for the late reverb .. .. .. Hz (?) late reflection cutoff 1500;
late reflection gain late reflection reverb level float 0 .. ∞ ? linear gain late reflection gain 0.7; a value above 1 increases the level
late reflection time 60 dB decay time for the late reflection level float ? autmoatic seconds late reflection time 1.2; this time is automatically calculated based on room model, but can be overwritten by this command
late reflection echo density determines the number of late reflections that occur per second. float 0 .. ∞ .. scalar late reflection echo density 0.8y; Values above 1 increase the echo density and values below 1 reduce it.
late reflection frequency density controls the spacing of late reflections in frequency terms. float 0 .. ∞ .. scalar late reflection frequency density 1; Values above 1 increase the echo density and values below 1 reduce it.
disable late reflections disables the late reflection none none ? none disable late reflections; ..
Room Dimensions defines the size of the shoe box shaped virtual room back_x, front_x, right_y, left_y, floor_z, ceiling_z .. -10, 20, -9, 11, -1, 8 meter (default) room{dimensions -26, 57, -35, 48, -1, 23;} front_x, left_y and ceiling_z are expected to be positive; back_x, right_y and floor_z are expected to be negative.
Room Reflections how much sound is reflected by the walls back, front, right, left, floor, ceiling 0..1 0.5, 0.5, 0.5, 0.5, 0.2, 0.6 coefficient room{reflections 0.7, 0.7, 0.7, 0.7, 0.3, 0.9;} 0: no reflection; 1: complete reflection

Parameter describing the position of loudspeakers

  • in VSpace, instead of loudspeakers, a recording situation with a set of virtual microphones is defined
    o Cardioid, Cardioid pairs, Figure-of-eight, Omnidirectional and Ambisonics (1st and 2nd order).

Example: a typical coincident X-Y `stereo pair' recording (facing forward with 90 degree separation)

recording stereo.wav {
device cardioid pair;
location <0,0,0>, <0,0,0>;
direction <1,1,0>, <1,-1,0>;
} 

parameter description data format range initial state unit example misc
device defines the simulated recording setup string cardioid / cardioid pair / omnidirectional / simple omnidirectional / figure-of-eight / ambisonic / second order ambisonic / simple ambisonic / simple second order ambisonic ? N/A device cardioid; "simple" means no early reflections or Doppler shift
location position of the device in the room 3 floats per microphone depends on room size .. unit location <0,0,0>, <0,0,0>; ..
direction direction of the device .. .. .. unit direction <1,1,0>, <1,-1,0>; Ambisonics mics are not directional.
core radius core sphere is the volume in which the inverse square law for gain due to distance is disabled. float ? 1 meter for ambisonics mics; 1 cm for all other mics meter (default) core radius radius;
recording gain gain stage for recoding float 0 .. ∞ 1.0 linear gain gain 0.7; ..

Other parameter

  • TODO: parameter describing a motion
parameter description data format range initial state unit example misc
tempo sets the tempo for the script ? ? 60 BPM tempo 90; All times in the script are interpreted as beats relative to this tempo.
miscParameter2 .. .. .. .. unit .. ..
miscParameter3 .. .. .. .. unit .. ..
miscParameter4 .. .. .. .. unit .. ..
miscParameter5 .. .. .. .. unit .. ..
miscParameter6 .. .. .. .. unit .. ..

Projects, sound, and music

  • art or research projects utilizing this spatial renderer

References

  • Bibliography

External Links

Media