[open] pyaudio error in inline script

Comments

• Edwin

  April 2014 edited 12:08AM

  According to the error message, you seem to be experiencing a problem in line 442 of an inline_script item called _inline_script. This problem originates from your use of the pyaudio module. It seems the device you are trying to use does not exist. These kind of things can happen e.g. when you use incorrect port numbers.

  Without further information we cannot provide any further help. Further information that would be useful is the specific inline_script (although with at least 442 lines, I hope a snippet of your code will suffice).

  Good luck!
• sholpan

  April 2014 edited April 2014

  Thank you for replying, Edwin
  This is the full inline_script that I used.

  """
  This example listens for a sound from the microphone.
  It has been adapted from:
  http://stackoverflow.com/questions/4160175/detect-tap-with-pyaudio-from-live-mic
  """
  
  # Measure the start of the response interval
  start_response_interval = self.time()
  
  import pyaudio
  
  TAP_THRESHOLD = 0.050
  FORMAT = pyaudio.paInt16 
  SHORT_NORMALIZE = (1.0/32768.0)
  CHANNELS = 2
  RATE = 44100  
  INPUT_BLOCK_TIME = 0.01
  INPUT_FRAMES_PER_BLOCK = int(RATE*INPUT_BLOCK_TIME)
  
  def get_rms( block ):
  
      """Get root mean square as a measure of loudness"""
  
      import struct
      import math 
  
      global SHORT_NORMALIZE
  
      count = len(block)/2
      format = "%dh" % (count)
      shorts = struct.unpack( format, block )
      sum_squares = 0.0
      for sample in shorts:
          n = sample * SHORT_NORMALIZE
          sum_squares += n*n
      return math.sqrt( sum_squares / count )
  
  # Open the mic
  stream = pyaudio.PyAudio().open(format = FORMAT,
      channels = CHANNELS,
      rate = RATE,
      input = True,
      input_device_index = 0,
      frames_per_buffer = INPUT_FRAMES_PER_BLOCK)
  
  # Listen until a sound has been detected
  while True:
      try:
          block = stream.read(INPUT_FRAMES_PER_BLOCK)
      except IOError, e:
          print e
      loudness = get_rms( block )
      if loudness > TAP_THRESHOLD:
          break
  
  self.experiment.set("response_time", self.time() - start_response_interval)
  self.experiment.set("loudness", loudness)
  
  # Close the mic
  stream.close()
  
  

  I'm still experiencing problems.
  Help please.
  Thanks guys!
• Edwin

  April 2014 edited April 2014

  Couple of questions:

  1) Is this the entire inline_script named "_inline_script"? Why did the previous error state an error in line 442? (clearly, this script is shorter: could it be that you have some leftover script in the unused items?)

  2) Are you sure there is a microphone attached? If yes: is the mic not accessed by any other piece of software? This seems to be a silly question, but your script looks fine, and your error indicates that there is no available device. So double-checking this is important!

  BTW: I just tested your code (using OpenSesame 2.8.0 on Ubuntu 12.04), and it runs fine. This means that it's likely not a problem with your script, but with your setup.