#! /usr/bin/env python

import sys
from aubio import source, sink, pvoc

if __name__ == '__main__':
  if len(sys.argv) < 2:
    print 'usage: %s <inputfile> <outputfile>' % sys.argv[0]
    sys.exit(1)
  samplerate = 44100
  f = source(sys.argv[1], samplerate, 256)
  g = sink(sys.argv[2], samplerate)
  total_frames, read = 0, 256

  win_s = 512                 # fft size
  hop_s = win_s / 2           # hop size
  pv = pvoc(win_s, hop_s)                            # phase vocoder

  while read:
    samples, read = f()
    spectrum = pv(samples)            # compute spectrum
    #spectrum.norm *= .8               # reduce amplitude a bit
    spectrum.phas[:] = 0.             # zero phase
    new_samples = pv.rdo(spectrum)    # compute modified samples
    g(new_samples, read)              # write to output
    total_frames += read

  print "wrote", total_frames, "from", f.uri, "to", g.uri