"OSError: No Default Input Device Available" on Google Colab

Question

I installed pyaudio using "pip3 install pyaudio" on Google Colab based on this answer from angelokh's.

Then, I got this error,

OSError: No Default Input Device Available

on Google Colab.

The code is shown below.

import speech_recognition as sr
r = sr.Recognizer()
with sr.Microphone() as source:
    r.adjust_for_ambient_noise(source)
    audio = r.listen(source)

Answer 1

You can't use the mic from Google Colab directly as you do with your own machine. You have to use JavaScript to let the browser enable the mic. This can be done using the following code found here:

# all imports
from io import BytesIO
from base64 import b64decode
from google.colab import output
from IPython.display import Javascript

RECORD = """
const sleep  = time => new Promise(resolve => setTimeout(resolve, time))
const b2text = blob => new Promise(resolve => {
  const reader = new FileReader()
  reader.onloadend = e => resolve(e.srcElement.result)
  reader.readAsDataURL(blob)
})
var record = time => new Promise(async resolve => {
  stream = await navigator.mediaDevices.getUserMedia({ audio: true })
  recorder = new MediaRecorder(stream)
  chunks = []
  recorder.ondataavailable = e => chunks.push(e.data)
  recorder.start()
  await sleep(time)
  recorder.onstop = async ()=>{
    blob = new Blob(chunks)
    text = await b2text(blob)
    resolve(text)
  }
  recorder.stop()
})
"""

def record(sec=3):
  print("Speak Now...")
  display(Javascript(RECORD))
  sec += 1
  s = output.eval_js('record(%d)' % (sec*1000))
  print("Done Recording !")
  b = b64decode(s.split(',')[1])
  return b #byte stream

Now you can use the record() function to record the audio. This function returns the audio as byte-stream. You can try it yourself on colab following this link: