vbaplsinit
vbaplsinit — Configures VBAP output according to loudspeaker parameters.
Initialization
idim -- dimensionality of loudspeaker array. Either 2 or 3. If the dimension has a fractional part then that is used as the index of the layout created (used in vbap, vbapz and vbapg only). The factional part should be between .00 and .99.
ilsnum -- number of loudspeakers. In two dimensions, the number can vary from 2 to 64. In three dimensions, the number can vary from 3 and 64.
idir1, idir2, ..., idir32 -- directions of loudspeakers. Number of directions must be less than or equal to 16. In two-dimensional loudspeaker positioning, idirn is the azimuth angle respective to nth channel. In three-dimensional loudspeaker positioning, fields are the azimuth and elevation angles of each loudspeaker consequently (azi1, ele1, azi2, ele2, etc.).
![[Note]](images/note.png)
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Note |
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| In 2 dimensions the angle between two adjacent speakers must be less than 179 degrees (170 degrees in earlier versions). This is a restriction of the algorithm. |
Performance
VBAP distributes the signal using loudspeaker data configured with vbaplsinit. The signal is applied to, at most, two loudspeakers in 2-D loudspeaker configurations, and three loudspeakers in 3-D loudspeaker configurations. If the virtual source is panned outside the region spanned by loudspeakers, the nearest loudspeakers are used in panning.
Examples
Here is an example of the vbaplsinit opcode. It uses the file vbaplsinit.csd.
Example 980. Example of the vbaplsinit opcode.
See the sections Real-time Audio and Command Line Flags for more information on using command line flags.
<CsoundSynthesizer> <CsOptions> ; Select audio/midi flags here according to platform -odac ;;;realtime audio out ;-iadc ;;;uncomment -iadc if realtime audio input is needed too ; For Non-realtime ouput leave only the line below: ; -o vbaplsinit.wav -W ;;; for file output any platform </CsOptions> <CsInstruments> sr = 44100 ksmps = 32 nchnls = 8 0dbfs = 1 vbaplsinit 2, 8, 0, 45, 90, 180, 270, 0, 0, 0 ;5 speakers for 5.1 amps instr 1 asig diskin2 "beats.wav", 1, 0, 1 ;loop beats.wav kazim line 1, p3, 355 a1,a2,a3,a4,a5,a6,a7,a8 vbap8 asig, kazim, 0, 1 ;change azimuth of soundsource ; Speaker mapping aFL = a1 ; Front Left aMF = a5 ; Mid Front aFR = a2 ; Front Right aBL = a3 ; Back Left aBR = a4 ; Back Right outo aFL,aFR,aBL,aBR,aMF,a6,a7,a8 ;a6, a7 and a8 are dummies endin </CsInstruments> <CsScore> i 1 0 5 e </CsScore> </CsoundSynthesizer>
See the other entries of the vbap opcodes for different examples.