fluidControl — Sends MIDI note on, note off, and other messages to a SoundFont preset.


fluidControl ienginenum, kstatus, kchannel, kdata1, kdata2


The fluid opcodes provide a simple Csound opcode wrapper around Peter Hanappe's Fluidsynth SoundFont2 synthesizer. This implementation accepts any MIDI note on, note off, controller, pitch bend, or program change message at k-rate. Maximum polyphony is 4096 simultaneously sounding voices. Any number of SoundFonts may be loaded and played simultaneously.


ienginenum -- engine number assigned from fluidEngine


kstatus -- MIDI channel message status byte: 128 for note off, 144 for note on, 176 for control change, 192 for program change, or 224 for pitch bend.

kchannel -- MIDI channel number to which the Fluidsynth program is assigned: from 0 to 255. MIDI channels numbered 16 or higher are virtual channels.

kdata1 -- For note on, MIDI key number: from 0 (lowest) to 127 (highest), where 60 is middle C. For continuous controller messages, controller number.

kdata2 -- For note on, MIDI key velocity: from 0 (no sound) to 127 (loudest). For continous controller messages, controller value.

Invoke fluidControl in instrument definitions that actually play notes and send control messages. Each instrument definition must consistently use one MIDI channel that was assigned to a Fluidsynth program using fluidLoad.

In this implementation, SoundFont effects such as chorus or reverb are used if and only if they are defaults for the preset. There is no means of turning such effects on or off, or of changing their parameters, from Csound.


Here is a more complex example of the fluidsynth opcodes written by Istvan Varga. It uses the file fluidcomplex.csd.

; Select audio/midi flags here according to platform
;Anna.mid is a midi file, a song by The Beatles and can be found on the internet
-odac -T -F  Anna.mid;;;realtime audio I/O and midifile in
;-iadc    ;;;uncomment -iadc if realtime audio input is needed too
; For Non-realtime ouput leave only the line below:
; -o fluidcomplex.wav -W ;;; for file output any platform

sr = 44100
ksmps = 32
nchnls = 2
0dbfs  = 1

; Example by Istvan Varga

; disable triggering of instruments by MIDI events

ichn = 1
        massign   ichn, 0
        loop_le   ichn, 1, 16, lp1
        pgmassign 0, 0

; initialize FluidSynth

gifld   fluidEngine
gisf2   fluidLoad "sf_GMbank.sf2", gifld, 1

; k-rate version of fluidProgramSelect

opcode fluidProgramSelect_k, 0, kkkkk
  keng, kchn, ksf2, kbnk, kpre xin
        igoto     skipInit
        fluidProgramSelect i(keng), i(kchn), i(ksf2), i(kbnk), i(kpre)
        reinit    doInit

instr 1
  ; initialize channels
  kchn  init 1
  if (kchn == 1) then
        fluidControl gifld, 192, kchn - 1, 0, 0
        fluidControl gifld, 176, kchn - 1, 7, 100
        fluidControl gifld, 176, kchn - 1, 10, 64
        loop_le   kchn, 1, 16, lp2

  ; send any MIDI events received to FluidSynth
  kst, kch, kd1, kd2 midiin
  if (kst != 0) then
    if (kst != 192) then
        fluidControl gifld, kst, kch - 1, kd1, kd2
        fluidProgramSelect_k gifld, kch - 1, gisf2, 0, kd1
      kgoto nxt

; get audio output from FluidSynth
  ivol   init 3 ;a bit louder
  aL, aR fluidOut gifld
         outs     aL*ivol, aR*ivol


i 1 0 3600


See Also

fluidEngine, fluidNote, fluidLoad

More information on soundfonts in the Floss Manuals: http://en.flossmanuals.net/csound/ch048_d-reading-midi-files

Other information on soundfonts on Wikipedia: http://en.wikipedia.org/wiki/Soundfont


Opcodes by Michael Gogins (gogins at pipeline dot com). Thanks to Peter Hanappe for Fluidsynth, and to Steven Yi for seeing that it is necessary to break up the Fluidsynth into several different Csound opcodes.

New in Csound5.00