是否有一个命令行可以用来了解声卡是仅捕获、仅播放还是“捕获和播放”？
我已经通过以下 pulseaudio 命令行找到了 pacmd：
pacmd list-cards
但我有点困惑，因为我的“插孔单声道到 USB”卡有输入和输出......
以下是 pacmd 生成的该声卡的输出：
index: 1
name: <alsa_card.usb-0d8c_C-Media_USB_Audio_Device-00>
driver: <module-alsa-card.c>
owner module: 8
properties:
alsa.card = "0"
alsa.card_name = "C-Media USB Audio Device"
alsa.long_card_name = "C-Media USB Audio Device at usb-0000:00:14.0-8, full speed"
alsa.driver_name = "snd_usb_audio"
device.bus_path = "pci-0000:00:14.0-usb-0:8:1.0"
sysfs.path = "/devices/pci0000:00/0000:00:14.0/usb1/1-8/1-8:1.0/sound/card0"
udev.id = "usb-0d8c_C-Media_USB_Audio_Device-00"
device.bus = "usb"
device.vendor.id = "0d8c"
device.vendor.name = "C-Media Electronics, Inc."
device.product.id = "0008"
device.product.name = "C-Media USB Audio Device "
device.serial = "0d8c_C-Media_USB_Audio_Device"
device.string = "0"
device.description = "C-Media USB Audio Device "
module-udev-detect.discovered = "1"
device.icon_name = "audio-card-usb"
profiles:
input:mono-fallback: Entrée Mono (priority 1, available: unknown)
input:multichannel-input: Entrée Multicanal (priority 1, available: unknown)
output:analog-stereo: Sortie Stéréo analogique (priority 6500, available: unknown)
output:analog-stereo+input:mono-fallback: Sortie Stéréo analogique + Entrée Mono (priority 6501, available: unknown)
output:analog-stereo+input:multichannel-input: Sortie Stéréo analogique + Entrée Multicanal (priority 6501, available: unknown)
output:iec958-stereo: Sortie Stéréo numérique (IEC958) (priority 5500, available: unknown)
output:iec958-stereo+input:mono-fallback: Sortie Stéréo numérique (IEC958) + Entrée Mono (priority 5501, available: unknown)
output:iec958-stereo+input:multichannel-input: Sortie Stéréo numérique (IEC958) + Entrée Multicanal (priority 5501, available: unknown)
off: Éteint (priority 0, available: unknown)
active profile: <output:analog-stereo+input:mono-fallback>
sinks:
alsa_output.usb-0d8c_C-Media_USB_Audio_Device-00.analog-stereo/#1: C-Media USB Audio Device Stéréo analogique
sources:
alsa_output.usb-0d8c_C-Media_USB_Audio_Device-00.analog-stereo.monitor/#2: Monitor of C-Media USB Audio Device Stéréo analogique
alsa_input.usb-0d8c_C-Media_USB_Audio_Device-00.mono-fallback/#3: C-Media USB Audio Device Mono
ports:
analog-input-mic: Microphone (priority 8700, latency offset 0 usec, available: unknown)
properties:
device.icon_name = "audio-input-microphone"
multichannel-input: Entrée multicanal (priority 0, latency offset 0 usec, available: unknown)
properties:
analog-output: Sortie analogique (priority 9900, latency offset 0 usec, available: unknown)
properties:
iec958-stereo-output: Sortie numérique (S/PDIF) (priority 0, latency offset 0 usec, available: unknown)
properties:
pacmd list-cards | grep -v -i -E "unknown|available: no" \
| grep -i -E "alsa.card_name|alsa.card = |output|input"
alsa.card = "1"
alsa.card_name = "USB Audio CODEC"
active profile: <output:analog-stereo+input:analog-stereo>
alsa_output.usb-Burr-Brown_from_TI_USB_Audio_CODEC-00.analog-stereo/#0: PCM2902 Audio Codec Stéréo analogique
alsa_output.usb-Burr-Brown_from_TI_USB_Audio_CODEC-00.analog-stereo.monitor/#0: Monitor of PCM2902 Audio Codec Stéréo analogique
alsa_input.usb-Burr-Brown_from_TI_USB_Audio_CODEC-00.analog-stereo/#1: PCM2902 Audio Codec Stéréo analogique
alsa.card = "0"
alsa.card_name = "C-Media USB Audio Device"
active profile: <output:analog-stereo+input:mono-fallback>
alsa_output.usb-0d8c_C-Media_USB_Audio_Device-00.analog-stereo/#1: C-Media USB Audio Device Stéréo analogique
alsa_output.usb-0d8c_C-Media_USB_Audio_Device-00.analog-stereo.monitor/#2: Monitor of C-Media USB Audio Device Stéréo analogique
alsa_input.usb-0d8c_C-Media_USB_Audio_Device-00.mono-fallback/#3: C-Media USB Audio Device Mono
device.icon_name = "audio-input-microphone"
alsa.card = "2"
alsa.card_name = "HDA Intel PCH"
active profile: <output:analog-stereo+input:analog-stereo>
alsa_output.pci-0000_00_1f.3.analog-stereo/#2: Audio interne Stéréo analogique
alsa_output.pci-0000_00_1f.3.analog-stereo.monitor/#4: Monitor of Audio interne Stéréo analogique
alsa_input.pci-0000_00_1f.3.analog-stereo/#5: Audio interne Stéréo analogique
device.icon_name = "audio-input-microphone"
device.icon_name = "audio-input-microphone"
analog-output-headphones: Casque audio (priority 9900, latency offset 0 usec, available: yes)
alsa.card = "3"
alsa.card_name = "HX Stomp"
active profile: <output:analog-surround-71+input:multichannel-input>
alsa_output.usb-LINE_6_HX_Stomp_3013138-01.analog-surround-71/#3: HX Stomp Analog Surround 7.1
alsa_output.usb-LINE_6_HX_Stomp_3013138-01.analog-surround-71.monitor/#6: Monitor of HX Stomp Analog Surround 7.1
alsa_input.usb-LINE_6_HX_Stomp_3013138-01.multichannel-input/#7: HX Stomp Multicanal