AdvancedLinuxSoundArchitecture.md

Advanced Linux Sound Architecture

Package Requirement Installation

root@edison:~# opkg install alsa-utils libportaudio2 libasound2 bison alsa-lib-dev alsa-utils-dev alsa-dev

Play Devices Identification

List all soundcards and digital audio devices

root@edison:~# aplay -l

...
...
card 1: dummyaudio [dummy-audio], device 0: 14 []
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 2: Device [USB PnP Sound Device], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
root@edison:~# 

Record Devices Identification

List all soundcards and digital audio devices

root@edison:~# arecord -l

...
...
card 1: dummyaudio [dummy-audio], device 0: 14 []
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 2: Device [USB PnP Sound Device], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 3: C525 [HD Webcam C525], device 0: USB Audio [USB Audio]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
root@edison:~/CodeLabs# 

ALSA Configuration

.asoundrc ALSA Project Asoundrc

Play & Record, One Single Device

Device USB Audio Dongle

root@edison:~# nano ~/.asoundrc
pcm.!default sysdefault:Device

Play & Capture, Two Devices

Devices:

• USB Audio Dongle (Play)
• USB Camera with Microphone (Record)

root@edison:~# vi ~/.asoundrc

pcm.!default {
        type asym
        playback.pcm {
                type plug
                slave.pcm "hw:2,0"
        }
        capture.pcm {
                type plug
                slave.pcm "hw:3,0"
        }
}

Arecord, Aplay

arecord, aplay - command-line sound recorder and player for ALSA soundcard driver

root@edison:~# aplay /usr/share/sounds/alsa/Front_Center.wav

root@edison:~# arecord ~/test.wav

root@edison:~# aplay ~/test.wav