# Program pa_record.py to record with a microphone
import os, pyaudio, re, wave
from sys import exit
#
# Start PyAudio
pa = pyaudio.PyAudio() # PyAudio instance
os.system('clear')     # clean the screen
try:
    did = pa.get_default_input_device_info()
except:
    print("Sorry, I cannot find any microphone!\n")
    pa.terminate()     # stop PyAudio
    raise
dha = pa.get_default_host_api_info()
#
# Set parameters
spr = int(did['defaultSampleRate']) # may try spr=16000
chs = 2 ; mod = "stereo"
if did['maxInputChannels']==1:
    chs = 1 ; mod = "mono"
fmt = pyaudio.paInt16  # 16 bit resolution
#
# Definition of variables
chk = 4096              # 2^12 samples for buffer
sec = 5.0               # desired recording time in s
n = int( (spr/chk) * sec ) + 1 # round up the duration
dur = (n * chk) / spr
fil = "voice.wav"       # path to output audio file
frames = []
#
# Print info
print(__file__)
print("audio recording with a microphone")
print("input device:", did['name']+",",mod)
print("host api (sound server):",dha['name'])
print("sample format: paInt16 (16 bit)")
print("duration of audio recording:",round(dur,1),"s")
#
# Recording
input("\nPress ENTER to start recording!")
stream = pa.open(
                 rate = spr,  # sampling rate
             channels = chs,  # number of channels
               format = fmt,  # sampling size and format
                input = True, # this is an input stream
   input_device_index = None, # uses default device
    frames_per_buffer = chk,  # frame number per buffer
)
for i in range(0, n):
     data = stream.read(chk,exception_on_overflow=False)
     frames.append(data)
stream.stop_stream()
stream.close()
#
# Stop PyAudio
pa.terminate()
#
# Save recorded data in WAV file
wf = wave.open(fil,"wb")
wf.setnchannels(chs)
wf.setsampwidth(pa.get_sample_size(fmt))
wf.setframerate(spr)
wf.writeframes(b''.join(frames))
wf.close()
print("\nthe audio file",fil,"was written,")
print("you may play it with: aplay",fil,"\n")