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bformenc

Codes a signal into the ambisonic B format.

Note that this opcode is deprecated as it is inaccurate, and is replaced by the much better opcode bformenc1 which replicates all the important features; also note that the gain arguments are not available in bformenc1.

Syntax

aw, ax, ay, az bformenc asig, kalpha, kbeta, kord0, kord1
aw, ax, ay, az, ar, as, at, au, av bformenc asig, kalpha, kbeta, \
                                            kord0, kord1 , kord2
aw, ax, ay, az, ar, as, at, au, av, ak, al, am, an, ao, ap, aq bformenc \
    asig, kalpha, kbeta, kord0, kord1, kord2, kord3

Performance

aw, ax, ay, ... -- output cells of the B format.

asig -- input signal.

kalpha -- azimuth angle in degrees (clockwise).

kbeta -- altitude angle in degrees.

kord0 -- linear gain of the zero order B format.

kord1 -- linear gain of the first order B format.

kord2 -- linear gain of the second order B format.

kord3 -- linear gain of the third order B format.

Example

Here is an example of the bformenc opcode. It uses the file bformenc.csd.

Example of the bformenc opcode.
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<CsoundSynthesizer>
<CsOptions>
; Select audio/midi flags here according to platform
; Audio out   Audio in    No messages
;-odac           -iadc     -d     ;;;RT audio I/O
; For Non-realtime ouput leave only the line below:
 -o bformenc.wav -W ;;; for file output any platform
</CsOptions>
<CsInstruments>
sr = 44100
kr = 4410
ksmps = 10
nchnls = 8

;bformenc is deprecated, please use bformenc1

instr 1
  ; generate pink noise
  anoise pinkish 1000

  ; two full turns
  kalpha line 0, p3, 720
  kbeta = 0

  ; fade ambisonic order from 2nd to 0th during second turn
  kord0 = 1
  kord1 linseg 1, p3 / 2, 1, p3 / 2, 0
  kord2 linseg 1, p3 / 2, 1, p3 / 2, 0

  ; generate B format
  aw, ax, ay, az, ar, as, at, au, av bformenc anoise, kalpha, kbeta, kord0, kord1, kord2

  ; decode B format for 8 channel circle loudspeaker setup
  a1, a2, a3, a4, a5, a6, a7, a8 bformdec 4, aw, ax, ay, az, ar, as, at, au, av

  ; write audio out
  outo a1, a2, a3, a4, a5, a6, a7, a8

</CsInstruments>
<CsScore>

; Play Instrument #1 for 20 seconds.
i 1 0 20
e


</CsScore>
</CsoundSynthesizer>

Credits

Author: Samuel Groner
2005

New in version 5.07. Deprecated in 5.09.