Offline batch generation of synthesis sounds  
============================================================================================================================================


**06-batch-synthesis.py**

This program demonstrates how to use pyo to do offline synthesis batch
generation.

.. code-block:: python

    import os
    from pyo import *
    
    # Initialize the Server in offline mode.
    s = Server(duplex=0, audio="offline")
    
    # Path to the output sound folder (user's home directory/pyo_batch_synth/).
    output_folder = os.path.join(os.path.expanduser("~"), "pyo_batch_synth")
    
    # Create the folder if it does not exist.
    if not os.path.isdir(output_folder):
        os.mkdir(output_folder)
    
    # Output file duration.
    dur = 2
    
    # How many file to generate.
    NUM = 12
    
    # Enter the batch synthesis loop.
    for i in range(NUM):
        # Boot the Server.
        s.boot()
    
        # Define the pitch of the note.
        note = 60 + i
        noteFreq = midiToHz(note)
    
        # Set recording parameters.
        s.recordOptions(
            dur=dur + 0.1, filename=os.path.join(output_folder, "file_%02d.wav" % note), fileformat=0, sampletype=0,
        )
    
        # Synthesis, an exponential envelope modulating a slightly out-of-tune stereo oscillator.
        env = Adsr(attack=0.005, decay=0.15, sustain=0.7, release=1.7, dur=dur).play()
        qenv = Pow(env, 4, mul=0.8)
        osc1 = SineLoop(freq=noteFreq, feedback=0.075, mul=qenv).out()
        osc2 = SineLoop(freq=noteFreq * 1.01, feedback=0.075, mul=qenv).out(1)
    
        # Start thw rendering.
        s.start()
    
        # Cleanup for the next pass.
        s.shutdown()
    
    print("Batch processing done!")

