pyjack-0.5.2/demos/capture.py

   1 #!/usr/bin/python
   2 # -*- coding: utf-8 -*-
   3 # Capture 3 seconds of stereo audio from alsa_pcm:capture_1/2; then play it back.
   4 #
   5 # Copyright 2003, Andrew W. Schmeder
   6 # This source code is released under the terms of the GNU Public License.
   7 # See LICENSE for the full text of these terms.
   8
   9 import numpy
  10 import jack
  11 import time
  12
  13 jack.attach("captest")
  14
  15 print jack.get_ports()
  16
  17 jack.register_port("in_1", jack.IsInput)
  18 jack.register_port("in_2", jack.IsInput)
  19 jack.register_port("out_1", jack.IsOutput)
  20 jack.register_port("out_2", jack.IsOutput)
  21
  22 jack.activate()
  23
  24 print jack.get_ports()
  25
  26 jack.connect("system:capture_1", "captest:in_1")
  27 jack.connect("system:capture_2", "captest:in_2")
  28 jack.connect("captest:out_1", "system:playback_1")
  29 jack.connect("captest:out_2", "system:playback_2")
  30
  31 print jack.get_connections("captest:in_1")
  32
  33 N = jack.get_buffer_size()
  34 Sr = float(jack.get_sample_rate())
  35 print "Buffer Size:", N, "Sample Rate:", Sr
  36 sec = 3.0
  37
  38 capture = numpy.zeros((2,int(Sr*sec)), 'f')
  39 input = numpy.zeros((2,N), 'f')
  40 output = numpy.zeros((2,N), 'f')
  41
  42 #time.sleep(1)
  43
  44 print "Capturing audio..."
  45
  46 i = 0
  47 while i < capture.shape[1] - N:
  48     try:
  49         jack.process(output, capture[:,i:i+N])
  50         i += N
  51     except jack.InputSyncError:
  52         print "Input Sync"
  53         pass
  54     except jack.OutputSyncError:
  55         print "Output Sync"
  56         pass
  57     print ".",
  58
  59 print "\nPlaying back..."
  60
  61 i = 0
  62 iS = 0
  63 oS = 0
  64 while i < capture.shape[1] - N:
  65     try:
  66         jack.process(capture[:,i:i+N], input)
  67         i += N
  68     except jack.InputSyncError:
  69         iS += 1
  70         pass
  71     except jack.OutputSyncError:
  72         iO += 1
  73         pass
  74 print "Finished with", iS, "input-off-sync &", oS, "output-off-sync"
  75
  76 jack.deactivate()
  77 jack.detach()
  78
  79 import numpy, scipy.io.wavfile
  80 toSave = numpy.array((2**15-1)*capture.transpose(),dtype="int16")
  81 scipy.io.wavfile.write("output.wav", int(Sr), toSave)