我正在使用 python 音频 alsa 库与我的 M-Audio Delta 1010LT PCI 音频接口(interface)交互。此音频接口(interface)有 8 个模拟输入。我想分析一个特定单声道输入的信号。正在识别卡片:
cat /proc/asound/cards 0 [M1010LT ]: ICE1712 - M Audio Delta 1010LT
M Audio Delta 1010LT at 0xa000, irq 18
之后，我使用“amixer”命令列出了所有设备名称(此处显示输入 ADC)
...
Simple mixer control 'ADC',0
Capabilities: volume volume-joined penum
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 164
Mono: 142 [87%] [7.50dB]
Simple mixer control 'ADC',1
Capabilities: volume volume-joined penum
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 164
Mono: 164 [100%] [18.50dB]
Simple mixer control 'ADC',2
Capabilities: volume volume-joined penum
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 164
Mono: 164 [100%] [18.50dB]
Simple mixer control 'ADC',3
Capabilities: volume volume-joined penum
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 164
Mono: 164 [100%] [18.50dB]
Simple mixer control 'ADC',4
Capabilities: volume volume-joined penum
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 164
Mono: 164 [100%] [18.50dB]
Simple mixer control 'ADC',5
Capabilities: volume volume-joined penum
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 164
Mono: 164 [100%] [18.50dB]
Simple mixer control 'ADC',6
Capabilities: volume volume-joined penum
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 164
Mono: 164 [100%] [18.50dB]
Simple mixer control 'ADC',7
Capabilities: volume volume-joined penum
Playback channels: Mono
Capture channels: Mono
Limits: 0 - 164
Mono: 164 [100%] [18.50dB]
...
之后我使用命令“arecord -l”列出了录音硬件设备
arecord -l**** List of CAPTURE Hardware Devices ****
card 0: M1010LT [M Audio Delta 1010LT], device 0: ICE1712 multi [ICE1712 multi]
Subdevices: 1/1
Subdevice #0: subdevice #0
我说的对吗？这是否只显示 1 个录音子设备？不应该显示 8 吗？
我还安装了 Mudita24 - 一个 envy24 可视化混音器。有了这个，我可以完美地调整和监控所有输入 channel 的电平。
之后，我使用 GStreamer 进行了一些测试，效果也很好:
gst-launch-0.10 alsasrc card-name=0 device-name='ADC 0' ! queue ! alsasink card-name=0 device-name='DAC 0'
但是我在使用以下卡和设备描述符来处理 python 的 alsa 中的某个单声道时遇到了麻烦:
'default' // This one get's me channel 1 & 2 MIXED (I'd like to get them as seperated mono inputs)
'hw:0,0' // recognizes device but the input value is 0
'hw:0,0,0' // returns same as hw:0,0
'hw:0,0,1' // Device or resource busy (pretty much every other value than 0 returns this)
'hw:0,1' // No such file or directory
如何使用 ALSA 处理特定的单声道输入 channel ？这是我正在使用的 python 库:link
这就是我尝试为每个 channel 创 build 备的方式:
pcm.one_channel {
@args [ CHANNEL ]
@args.CHANNEL { type integer }
type dsnoop
ipc_key 20130206
slave {
pcm "hw:0"
channels 12
rate 44000
}
bindings [ $CHANNEL ]
}
pcm.two_channel {
@args [ CHANNEL ]
@args.CHANNEL { type integer }
type dsnoop
ipc_key 20130206
slave {
pcm "hw:0"
channels 12
rate 44000
}
bindings [ $CHANNEL ]
}
pcm.three_channel {
@args [ CHANNEL ]
@args.CHANNEL { type integer }
type dsnoop
ipc_key 20130206
slave {
pcm "hw:0"
channels 12
rate 44000
}
bindings [ $CHANNEL ]
}
pcm.four_channel {
@args [ CHANNEL ]
@args.CHANNEL { type integer }
type dsnoop
ipc_key 20130206
slave {
pcm "hw:0"
channels 12
rate 44000
}
bindings [ $CHANNEL ]
}
pcm.five_channel {
@args [ CHANNEL ]
@args.CHANNEL { type integer }
type dsnoop
ipc_key 20130206
slave {
pcm "hw:0"
channels 12
rate 44000
}
bindings [ $CHANNEL ]
}
我是否正确解读了您的建议？我也一直在网上寻找这个并找到了这张卡的另外两个 .asoundrc(遗憾的是也不起作用)。
#
# M-Audio Delta 1010
#
pcm.ice1712_capture {
type dsnoop
ipc_key 1024
slave {
pcm "hw:0"
period_size 0
buffer_size 65536
rate 44100
channels 10
format "S16_LE"
}
}
pcm.ice1712_playback {
type dsnoop
ipc_key 1024
slave {
pcm "hw:0"
period_size 0
buffer_size 65536
rate 44100
channels 10
format "S16_LE"
}
}
pcm.ice1712_duplex {
type asym
playback.pcm ice1712_playback
capture.pcm ice1712_capture
}
pcm.ch1 {
type plug
ttable.0.0 1
slave.pcm ice1712_duplex
}
pcm.ch2 {
type plug
ttable.1.1 1
slave.pcm ice1712_duplex
}
pcm.ch3 {
type plug
ttable.0.2 1
slave.pcm ice1712_duplex
}
pcm.ch4 {
type plug
ttable.1.3 1
slave.pcm ice1712_duplex
}
pcm.ice1712_ch5 {
type plug
ttable.0.4 1
slave.pcm ice1712_duplex
}
pcm.ice1712_ch6 {
type plug
ttable.1.5 1
slave.pcm ice1712_duplex
}
pcm.ice1712_ch7 {
type plug
ttable.0.6 1
slave.pcm ice1712_duplex
}
pcm.ice1712_ch8 {
type plug
ttable.1.7 1
slave.pcm ice1712_duplex
}
pcm.ice1712_ch9 {
type plug
ttable.0.8 1
slave.pcm ice1712_duplex
}
pcm.ice1712_ch10 {
type plug
ttable.1.9 1
slave.pcm ice1712_duplex
}
还有一个:
pcm.multi_capture {
type multi
slaves.a.pcm hw:0
slaves.a.channels 12
# First 8 channels of first soundcard (capture)
bindings.0.slave a
bindings.0.channel 0
bindings.1.slave a
bindings.1.channel 1
bindings.2.slave a
bindings.2.channel 2
bindings.3.slave a
bindings.3.channel 3
bindings.4.slave a
bindings.4.channel 4
bindings.5.slave a
bindings.5.channel 5
bindings.6.slave a
bindings.6.channel 6
bindings.7.slave a
bindings.7.channel 7
# S/PDIF section. Uncomment bindings if required.
# S/PDIF first soundcard (capture)
#bindings.16.slave a
#bindings.16.channel 8
#bindings.17.slave a
#bindings.17.channel 9
}
ctl.multi_capture {
type hw
card 0
}
pcm.multi_playback {
type multi
slaves.a.pcm hw:0
slaves.a.channels 10
# First 8 channels of first soundcard (playback)
bindings.0.slave a
bindings.0.channel 0
bindings.1.slave a
bindings.1.channel 1
bindings.2.slave a
bindings.2.channel 2
bindings.3.slave a
bindings.3.channel 3
bindings.4.slave a
bindings.4.channel 4
bindings.5.slave a
bindings.5.channel 5
bindings.6.slave a
bindings.6.channel 6
bindings.7.slave a
bindings.7.channel 7
# S/PDIF section. Uncomment bindings if required.
# S/PDIF first soundcard (playback)
#bindings.16.slave a
#bindings.16.channel 8
#bindings.17.slave a
#bindings.17.channel 9
}
ctl.multi_playback {
type hw
card 0
}
最佳答案
amixer 工具不显示设备名称，而是显示混音器控件。
ICE1712芯片确实只有一个采集设备(恰好有12个 channel )。
要为各个 channel 获取虚拟设备，请尝试将如下内容添加到您的 ~/.asoundrc 或 /etc/asound.conf:
pcm.one_channel {
@args [ CHANNEL ]
@args.CHANNEL { type integer }
type dsnoop
ipc_key 20130206
slave {
pcm "hw:0"
channels 12
rate 48000
}
bindings [ $CHANNEL ]
}
然后使用设备名称，如 one_channel:0、one_channel:1 等
关于python - ALSA & Python - 捕获多个单声道音频输入，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/14725257/