record output sound in python
- by aaronstacy
i want to programatically record sound coming out of my laptop in python. i found PyAudio and came up with the following program that accomplishes the task:
import pyaudio, wave, sys
chunk = 1024
FORMAT = pyaudio.paInt16
CHANNELS = 1
RATE = 44100
RECORD_SECONDS = 5
WAVE_OUTPUT_FILENAME = sys.argv[1]
p = pyaudio.PyAudio()
channel_map = (0, 1)
stream_info = pyaudio.PaMacCoreStreamInfo(
flags = pyaudio.PaMacCoreStreamInfo.paMacCorePlayNice,
channel_map = channel_map)
stream = p.open(format = FORMAT,
rate = RATE,
input = True,
input_host_api_specific_stream_info = stream_info,
channels = CHANNELS)
all = []
for i in range(0, RATE / chunk * RECORD_SECONDS):
data = stream.read(chunk)
all.append(data)
stream.close()
p.terminate()
data = ''.join(all)
wf = wave.open(WAVE_OUTPUT_FILENAME, 'wb')
wf.setnchannels(CHANNELS)
wf.setsampwidth(p.get_sample_size(FORMAT))
wf.setframerate(RATE)
wf.writeframes(data)
wf.close()
the problem is i have to connect the headphone jack to the microphone jack. i tried replacing these lines:
input = True,
input_host_api_specific_stream_info = stream_info,
with these:
output = True,
output_host_api_specific_stream_info = stream_info,
but then i get this error:
Traceback (most recent call last):
File "./test.py", line 25, in
data = stream.read(chunk)
File "/Library/Python/2.5/site-packages/pyaudio.py", line 562, in read
paCanNotReadFromAnOutputOnlyStream)
IOError: [Errno Not input stream] -9975
is there a way to instantiate the PyAudio stream so that it inputs from the computer's output and i don't have to connect the headphone jack to the microphone? is there a better way to go about this? i'd prefer to stick w/ a python app and avoid cocoa.
