[open] Audio threshold

Comments

• sebastiaan

  March 2014 edited 8:37AM

  Hi,

  In principle, creating and closing a stream for every trial should be fine. From you code snippet it's not clear how you are trying to do this exactly. Are you sure that you are closing the stream? Working examples can be found in this discussion:

  • http://forum.cogsci.nl/index.php?p=/discussion/6/solved-voicekey-input-triggering-responses-through-sound-input

  If the issue persists, could you remove the try ... except ... from your code and post the stacktrace from the debug window? The error message should give some insight into what goes wrong.

  Alternatively, I suppose you could create a stream object at the start of the experiment (in the same way as you're doing now), and call stream.start_stream() at the start of the trial, and stream.stop_stream() at the end. For documentation, see:

  • http://people.csail.mit.edu/hubert/pyaudio/docs/#pyaudio.Stream.start_stream

  But I would think that simply creating a new stream on every trial should work just as well.

  Cheers!
  Sebastiaan

  
  
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• snufkin

  March 2014 edited 8:37AM

  hi sebastiaan
  Thanks for the quik answer

  It seems that sometimes the pyaudio gets an garbage as an input, very high values from the mic.

  Here is the complete code

  import pyaudio 
  import serial
  import time
  from time import sleep 
  from openexp.keyboard import keyboard
  time1=self.time()
  
  flagn=0 # this flag is the 'r' option flag that will stop the rotation 
  my_keyboard = keyboard(exp, keylist=['escape'], timeout=1)
  my_keyboard2 = keyboard(exp, keylist=['1','2','3','4','5','6','7','8','9','0',None], timeout=1600) #1/3this should be changed according to how much time we need after each vibration in miliseconds
  
  # fixation point
  from openexp.canvas import canvas
  my_canvas = canvas(exp)
  my_canvas.set_penwidth(8) #penwidth
  my_canvas.line(410, 390, 610, 390)  #here you can change the fixation
  my_canvas.line(510, 290, 510, 490)
  my_canvas.show()
  #self.sleep(1000)
  #end fixation point
  
  
  
  #ser = serial.Serial("com30", 9600)
  time.sleep(2)
  exp.ser.bytesize = serial.EIGHTBITS
  
  
  
  
  
  in1 = self.experiment.get("f1")
  in2 = self.experiment.get("f2")
  in3 = self.experiment.get("f3")
  in4 = self.experiment.get("f4")
  in5 = self.experiment.get("f5")
  in6 = self.experiment.get("f6")
  in7 = self.experiment.get("f7")
  in8 = self.experiment.get("f8")
  in9 = self.experiment.get("f9")
  in10 = self.experiment.get("f10")
  
  
  vol = self.experiment.get("volume")
  
  modevt = self.experiment.get("mode")
  
  timeop = int(self.experiment.get("timemili")/10)
  
  
  regb = 0
  regd = 0
  regb = in6 + in7*2 + in8*4 + in9*8 + in10*16 + 32
  
  regd = in1*1 + in2*4 + in3*8 + in4*16 + in5*32
  
  
  
  if modevt == 'a':
      exp.ser.write('a')
      time.sleep(0.025)
      #exp.ser.close()
  
  
  #the beep code
  from openexp.sampler import sampler
  #src = exp.get_file('C:\Program Files (x86)\OpenSesame\sounds\pi.wav')
  src = exp.get_file('pi.wav')
  my_sampler = sampler(exp, src)
  my_sampler.play()
  #bip = self.experiment.get("beeptime")
  bip = 200
  self.sleep(bip)
  #end of beep code
  
  
  #microphone def
  
  if modevt == 't':
      exp.ser.write('t')
      exp.ser.write(chr(regb))
      exp.ser.write(chr(regd))
      exp.ser.write(chr(timeop))
      exp.ser.write(chr(vol))
  
      time.sleep(0.01)
      #exp.ser.close()
  
  
  if modevt == 'r':
      flagn=1
      exp.ser.write('r')
      exp.ser.write(chr(regb))
      exp.ser.write(chr(regd))
      exp.ser.write(chr(vol))
  
      start_response_interval = self.time()
  
      # Listen until a sound has been detected
  
  #TAP_THRESHOLD = 0.1
  TAP_THRESHOLD = self.experiment.get("mic")
  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
  try:
      stream = pyaudio.PyAudio().open(format = FORMAT,
      channels = CHANNELS,
      rate = RATE,
      input = True,
      input_device_index = 0,
      frames_per_buffer = INPUT_FRAMES_PER_BLOCK)
  except IOError, e:
      print e
      print "mic stream error1"
  
  normal_exit = 0
  esc_exit = 0
  
  start_response_interval = self.time()
  # Listen until a sound has been detected
  maxtime=self.time()
  while True:
          try:        
              my_keyboard.get_key()
              #if response == None:           
              block = stream.read(INPUT_FRAMES_PER_BLOCK)
              loudness = get_rms( block )
              if loudness > TAP_THRESHOLD:
                  print "mic exit"
                  normal_exit = 1             
                  self.experiment.set("response_time", self.time() - start_response_interval)
                  if flagn == 1 :
                      exp.ser.write('n')
                  # Close the mic
                  stream.stop_stream()
                  stream.close()
                  break   
              if self.time()-maxtime > 3000:
                  normal_exit = 1             
                  self.experiment.set("response_time", self.time() - start_response_interval)
                  if flagn == 1 :
                      exp.ser.write('n')
                  print "max time"
                  stream.stop_stream()
                  stream.close()
                  break
          except IOError, e:
              print e
              print "mic stream error"
              if flagn == 1 :
                      exp.ser.write('n')
              self.experiment.set("response_time", "check if mic is connected")
              # Close the mic
              stream.stop_stream()
              stream.close()
              break
          except Exception:
              print "esc exit"
              if flagn == 1 :
                      exp.ser.write('n')
              self.experiment.set("response_time", "problem, escape was pressed during test")
              # Close the mic
              stream.stop_stream()
              stream.close()
              esc_exit = 1
              raise
              break
  
  
  
  
  if normal_exit == 1: #normal exit and not exception
      end_time2 = self.time()
      my_keyboard2.flush()
      responsek, timeout2 = my_keyboard2.get_key()
      self.experiment.set("responsek", responsek)
      #print timeout2
      #print end_time2
      end_time22= self.time()
      if end_time22- end_time2 < 1599:
          #print timeout2
          print "working"
          eittime = float(float(0) - float(end_time2 - end_time22)/1000) #3/3this should be changed according to how much time we need after each vibration in seconds
          print "eittime = %.4f" %(eittime)
          time.sleep(1.6-eittime)
  
• sebastiaan

  March 2014 edited 8:37AM

  Hmm, ok, but what exactly is the problem here? I took your previous post to mean that you occasionally get an error when you open a new stream. But now it sounds like the stream is opening fine, but you're getting funny-sounding input from the mic.

  Could you be a bit more specific about what the problem is exactly? Please also include full error messages (from the debug window) if there are any.

  
  
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• snufkin

  March 2014 edited 8:37AM

  Hi
  Thanks for the help, I really need it…
  the problem is that some times when i open the stream it gets a value of 8000 from the stream,
  and some times it is ok and stops just when I talk.

  This code runs in a loop many times.
  the problem shows up just on an opening of the stream, and never appeared on the first time that I open the stream.

  this led me to the conclusion that if I'll open the stream just once outside of the loop it will be ok…
• sebastiaan

  April 2014 edited April 2014

  the problem is that some times when i open the stream it gets a value of 8000 from the stream,

  I'm afraid that you're still not being specific enough!

  What exactly has a value of 8000, and where did you get this value from? Is 8000 the loudness returned by get_rms() that you printed to the debug window or something like that? If so, is 8000 even an unusual value, and, if it is, what are usual values? Also, if error messages are not the problem, why do you have so many try ... except ... statements in your code? These generally just hide problems and make scripts more difficult to debug, so unless there is a good reason I would remove them.

  You really need to provide a detailed explanation of the problem for anyone to shed some light on it.

  As an aside, if you haven't already done so, I would also record some microphone input with a tool like Audacity. If this looks normal, then you know at least that the microphone input itself is fine.

  Cheers,
  Sebastiaan

  
  
  Check out SigmundAI.eu for our OpenSesame AI assistant!