record output sound in python

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.

ansaurus

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record output sound in python

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