How do I get the system output volume in python?

Question

I'm working on a project where I need to get the current system audio output level within Python. Basically, I want to know how loud the current sound coming out of the speakers are using Python on a Linux system. I don't need to know the exact volume level of the speakers, the relative volume is what I'm looking for. I haven't found any good resources online for this.

Answer 1

tl;dr - An alternative answer for getting the discrete system output volume on macOS.

After seeing your question and learning that I can't build pyalsaaudio on macOS, I wanted to provide an additional answer for how this could be done on macOS specifically since it's not abstracted in a cross-platform way.

(I know this won't be helpful to your immediate use case, but I have a hunch I'm not the only Mac user that will stumble by this question interested in a solution that we can run too.)

On macOS, you can get the output volume by running a little AppleScript:

$ osascript -e 'get volume settings'
output volume:13, input volume:50, alert volume:17, output muted:false

I wrapped that call in a Python function to parse volume + mute state into a simple 0–100 range:

import re
import subprocess


def get_speaker_output_volume():
    """
    Get the current speaker output volume from 0 to 100.

    Note that the speakers can have a non-zero volume but be muted, in which
    case we return 0 for simplicity.

    Note: Only runs on macOS.
    """
    cmd = "osascript -e 'get volume settings'"
    process = subprocess.run(cmd, stdout=subprocess.PIPE, shell=True)
    output = process.stdout.strip().decode('ascii')

    pattern = re.compile(r"output volume:(\d+), input volume:(\d+), "
                         r"alert volume:(\d+), output muted:(true|false)")
    volume, _, _, muted = pattern.match(output).groups()

    volume = int(volume)
    muted = (muted == 'true')

    return 0 if muted else volume

For example, on a MacBook Pro at various volume bar settings:

>>> # 2/16 clicks
>>> vol = get_speaker_output_volume()
>>> print(f'Volume: {vol}%')
Volume: 13%
>>> # 2/16 clicks + muted
>>> get_speaker_output_volume()
0
>>> # 16/16 clicks
>>> get_speaker_output_volume()
100