CODEWITHSUNDEEP
pythonmacosaudioaudio-streaming
aaronstacy
aaronstacy

Reputation: 6428

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.

Upvotes: 11

Views: 15686

Answers (1)

HaHeho
HaHeho

Reputation: 21

Doing this programmatically will be tricky. Basically, it is not possible to intercept the audio traffic in front of your "output". Therefore, what you would have to do is create your own virtual audio device and make whatever application you want to capture play to that device.

Different third-party applications also mentioned by other people seem to provide such capabilities on MacOS. I can add Loopback but I have no experience with either of the tools.

Programmatically, you would have to mimic something exactly like that.

Upvotes: 0

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