Getting list of audio input devices in Python

Question

How do I get the list of audio input devices in Linux using Python in this format as hw:0,1?

I've tried the following using pyaudio:

def getaudiodevices():
        p = pyaudio.PyAudio()
        print p.get_default_input_device_info()
        for i in range(p.get_device_count()):
                print ''#p.get_device_info_by_index(i)

I'm also able to retrieve using "arecord -l" but I need to just get it like:

hw:0,1
hw:0,2

What can I try next?

Answer 1

If the name stored by the PaDeviceInfo structure is sufficient, then you could just access the 'name' from the dict returned by get_device_info_by_index(), and then perhaps slice the information off the end:

import pyaudio

def getaudiodevices():
    p = pyaudio.PyAudio()
    for i in range(p.get_device_count()):
        print p.get_device_info_by_index(i).get('name')

gives me

HDA Intel HDMI: 0 (hw:0,3)
HDA Intel HDMI: 1 (hw:0,7)
HDA Intel HDMI: 2 (hw:0,8)
HDA Intel PCH: CS4208 Analog (hw:1,0)
HDA Intel PCH: CS4208 Digital (hw:1,1)
hdmi
default

But this doesn't give you what you want with the default devices, the name seems to be stored as "default". In that case, executing "arecord -l" in Python can work, if that's what you're looking for. Of course, you can do the same thing for "aplay -l".

import os

def getaudiodevices():
    devices = os.popen("arecord -l")
    device_string = devices.read()
    device_string = device_string.split("\n")
    for line in device_string:
            if(line.find("card") != -1):
                print "hw:" + line[line.find("card")+5] + "," +\
 line[line.find("device")+7]

outputs

hw:1,0