映像だけでなく、音声の入出力デバイスも確認したいのでその方法を調べた。
参考 :
aplayを利用するaplay --list-devicesで出力デバイスの一覧を取得できる。
Find the hardware address
Using aplay
The stock ALSA utility
aplaycan tell you the hardware addresses of the devices it is ready to use. Simply supply to aplay the--list-devicesargument.$ aplay --list-devices **** List of PLAYBACK Hardware Devices **** card 0: HDMI [HDA ATI HDMI], device 3: ATI HDMI [ATI HDMI] Subdevices: 1/1 Subdevice #0: subdevice #0Note, for this card the notation for the physical address would be
hw:0,3. While the device name, is HDMI
$ aplay --list-devices
**** List of PLAYBACK Hardware Devices ****
card 0: PCH [HDA Intel PCH], device 0: CS4206 Analog [CS4206 Analog]
Subdevices: 0/1
Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 1: CS4206 Digital [CS4206 Digital]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 3: HDMI 0 [HDMI 0]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 7: HDMI 1 [HDMI 1]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: PCH [HDA Intel PCH], device 8: HDMI 2 [HDMI 2]
Subdevices: 1/1
Subdevice #0: subdevice #0
arecordを利用するarecord -lで取得できる。もちろん、arecord --list-devicesでも可能。
Display all soundcards and digital audio devices
Type the following command:
$ arecord -lOutputs:
**** List of CAPTURE Hardware Devices **** card 0: Intel [HDA Intel], device 0: STAC92xx Analog [STAC92xx Analog] Subdevices: 2/2 Subdevice #0: subdevice #0 Subdevice #1: subdevice #1 card 1: SAA7134 [SAA7134], device 0: SAA7134 PCM [SAA7134 PCM] Subdevices: 1/1 Subdevice #0: subdevice #0You need to use card number and device number while playing various media. For example, to play a radiostation (FM freq # 98.3) from card #1 and device 0 (hw=.), enter:
$ mplayer radio://98.3 -radio driver=v4l2:device=/dev/radio0:adevice=hw=1.0
$ arecord -l
**** List of CAPTURE Hardware Devices ****
card 0: PCH [HDA Intel PCH], device 0: CS4206 Analog [CS4206 Analog]
Subdevices: 1/1
Subdevice #0: subdevice #0
card 1: U0x46d0x821 [USB Device 0x46d:0x821], device 0: USB Audio [USB Audio]
Subdevices: 1/1
Subdevice #0: subdevice #0