Python Scripting

You can use CsoundAC as a Python extension module. You can do this in a standard Python interpreter, such as Python command line or the Idle Python GUI.

To use CsoundAC in a standard Python interpreter, import CsoundAC.

      import CsoundAC

The CsoundAC module automatically creates an instance of CppSound named csound, which provides an object-oriented interface to the Csound API. In a standard Python interpreter, you can load a Csound .csd file and perform it like this:

      C:\Documents and Settings\mkg>python
      Python 2.3.3 (#51, Dec 18 2003, 20:22:39) [MSC v.1200 32 bit (Intel)] on win32
      Type "help", "copyright", "credits" or "license" for more information.
      >>> import CsoundAC
      >>> csound.load("c:/projects/csound5/examples/trapped.csd")
      1
      >>> csound.exportForPerformance()
      1
      >>> csound.perform()
      BEGAN CppSound::perform(5, 988ee0)...
      BEGAN CppSound::compile(5, 988ee0)...
      Using default language
      0dBFS level = 32767.0
      Csound version 5.00 beta (float samples) Jun  7 2004
      libsndfile-1.0.10pre6
      orchname:  temp.orc
      scorename: temp.sco
      orch compiler:
      398 lines read
      instr   1
      instr   2
      instr   3
      instr   4
      instr   5
      instr   6
      instr   7
      instr   8
      instr   9
      instr   10
      instr   11
      instr   12
      instr   13
      instr   98
      instr   99
      sorting score ...
      ... done
      Csound version 5.00 beta (float samples) Jun  6 2004
      displays suppressed
      0dBFS level = 32767.0
      orch now loaded
      audio buffered in 16384 sample-frame blocks
      SFDIR undefined.  using current directory
      writing 131072-byte blks of shorts to test.wav
      WAV
      SECTION 1:
      ENDED CppSound::compile.
      ftable 1:
      ftable 2:
      ftable 3:
      ftable 4:
      ftable 5:
      ftable 6:
      ftable 7:
      ftable 8:
      ftable 9:
      ftable 10:
      ftable 11:
      ftable 12:
      ftable 13:
      ftable 14:
      ftable 15:
      ftable 16:
      ftable 17:
      ftable 18:
      ftable 19:
      ftable 20:
      ftable 21:
      ftable 22:
      new alloc for instr 1:
      B  0.000 ..  1.000 T  1.000 TT  1.000 M:     32.7      0.0
      new alloc for instr 1:
      B  1.000 ..  3.600 T  3.600 TT  3.600 M:    207.6      0.1
      
      ...
      
      B 93.940 .. 94.418 T 98.799 TT281.799 M:    477.6     85.0
      B 94.418 ..100.000 T107.172 TT290.172 M:    118.9     11.5
      end of section 4         sect peak amps:  25950.8  26877.4
      inactive allocs returned to freespace
      end of score.              overall amps:  32204.8  31469.6
      overall samples out of range:        0        0
      0 errors in performance
      782 131072-byte soundblks of shorts written to test.wav WAV
      Elapsed time = 13.469000 seconds.
      ENDED CppSound::perform.
      1
      >>>
    

The koch.py script shows how to use Python to do algorithmic composition for Csound. You can use Python triple-quoted string literals to hold your Csound files right in your script, and assign them to Csound:

      csound.setOrchestra('''sr = 44100
      kr = 441
      ksmps = 100
      nchnls = 2
      0dbfs = .1
      instr 1,2,3,4,5 ; FluidSynth General MID
      I; INITIALIZATION
      ; Channel, bank, and program determine the preset, that is, the actual sound.
      ichannel		=			p1
      iprogram		=			p6
      ikey	 		= 			p4
      ivelocity 		= 			p5 + 12
      ijunk6 			= 			p6
      ijunk7			=			p7
      ; AUDIO
      istatus			=			144;
      print			iprogram, istatus, ichannel, ikey, ivelocityaleft, aright
      fluid			"c:/projects/csound5/samples/VintageDreamsWaves-v2.sf2", \\
      iprogram, istatus, ichannel, ikey, ivelocity, 1
      outs 			aleft, arightendin''')
      csound.setCommand("csound --opcode-lib=c:/projects/csound5/fluid.dll \\
      -RWdfo ./koch.wav ./temp.orc ./temp.sco")
      csound.exportForPerformance()
      csound.perform()