| |
""" Record a few seconds of audio and save to a WAVE file. |
| |
Based on http://stackoverflow.com/questions/892199/detect-record-audio-in-python/6743593#6743593 |
| |
""" |
| |
|
| |
import pyaudio |
| |
import wave |
| |
import sys |
| |
import audioop # http://docs.python.org/library/audioop |
| |
from os.path import exists |
| |
from array import array |
| |
from struct import unpack, pack |
| |
import threading |
| |
|
| |
CHANNELS = 1 |
| |
THRESHOLD = 500 |
| |
CHUNK_SIZE = 1024 |
| |
FORMAT = pyaudio.paInt16 |
| |
RATE = 44100 |
| |
|
| |
def is_silent(L): |
| |
"Returns `True` if below the 'silent' threshold" |
| |
"print max(L)" |
| |
"print max(L) < THRESHOLD" |
| |
return max(L) < THRESHOLD |
| |
|
| |
def normalize(L): |
| |
"Average the volume out" |
| |
MAXIMUM = 16384 |
| |
times = float(MAXIMUM)/max(abs(i) for i in L) |
| |
|
| |
LRtn = array('h') |
| |
for i in L: |
| |
LRtn.append(int(i*times)) |
| |
return LRtn |
| |
|
| |
def trim(L): |
| |
"Trim the blank spots at the start and end" |
| |
def _trim(L): |
| |
snd_started = False |
| |
LRtn = array('h') |
| |
|
| |
for i in L: |
| |
if not snd_started and abs(i)>THRESHOLD: |
| |
snd_started = True |
| |
LRtn.append(i) |
| |
|
| |
elif snd_started: |
| |
LRtn.append(i) |
| |
return LRtn |
| |
|
| |
# Trim to the left |
| |
L = _trim(L) |
| |
|
| |
# Trim to the right |
| |
L.reverse() |
| |
L = _trim(L) |
| |
L.reverse() |
| |
return L |
| |
|
| |
def add_silence(L, seconds): |
| |
"Add silence to the start and end of `L` of length `seconds` (float)" |
| |
LRtn = array('h', [0 for i in xrange(int(seconds*RATE))]) |
| |
LRtn.extend(L) |
| |
LRtn.extend([0 for i in xrange(int(seconds*RATE))]) |
| |
return LRtn |
| |
|
| |
def record(): |
| |
""" |
| |
Record a word or words from the microphone and |
| |
return the data as an array of signed shorts. |
| |
|
| |
Normalizes the audio, trims silence from the |
| |
start and end, and pads with 0.5 seconds of |
| |
blank sound to make sure VLC et al can play |
| |
it without getting chopped off. |
| |
""" |
| |
p = pyaudio.PyAudio() |
| |
stream = p.open(format=FORMAT, channels=1, rate=RATE, |
| |
input=True, output=True, |
| |
frames_per_buffer=CHUNK_SIZE) |
| |
|
| |
num_silent = 0 |
| |
snd_started = False |
| |
|
| |
LRtn = array('h') |
| |
|
| |
while 1: |
| |
data = stream.read(CHUNK_SIZE) |
| |
L = unpack('<' + ('h'*(len(data)/2)), data) # little endian, signed short |
| |
L = array('h', L) |
| |
LRtn.extend(L) |
| |
|
| |
silent = is_silent(L) |
| |
#print silent, num_silent, L[:10] |
| |
|
| |
if silent and snd_started: |
| |
num_silent += 1 |
| |
print num_silent |
| |
elif not silent and not snd_started: |
| |
snd_started = True |
| |
print snd_started |
| |
if snd_started and num_silent > 30: |
| |
break |
| |
|
| |
sample_width = p.get_sample_size(FORMAT) |
| |
stream.stop_stream() |
| |
stream.close() |
| |
p.terminate() |
| |
|
| |
LRtn = normalize(LRtn) |
| |
LRtn = trim(LRtn) |
| |
LRtn = add_silence(LRtn, 0.5) |
| |
return sample_width, LRtn |
| |
|
| |
def record_to_file(path): |
| |
"Records from the microphone and outputs the resulting data to `path`" |
| |
sample_width, data = record() |
| |
data = pack('<' + ('h'*len(data)), *data) |
| |
|
| |
wf = wave.open(path, 'wb') |
| |
wf.setnchannels(1) |
| |
wf.setsampwidth(sample_width) |
| |
wf.setframerate(RATE) |
| |
wf.writeframes(data) |
| |
wf.close() |
| |
print("done - result written to "+path) |
| |
|
| |
|
| |
|
| |
|
| |
if __name__ == '__main__': |
| |
filename = 'demo.wav' |
| |
record_to_file(filename) |
| |
print("done - result written to "+filename) |
| |
|