实现项目量产过程中,要测试一些外设,比如智能音箱的麦克风测试,测试麦克风的步骤比较复杂,比如验证麦克风的一致性,降噪算法等等,这里只是初步验证下麦克风的好坏,验证麦克风的好坏无非就是录音,然后查看录音文件数据。
录音采用ALSA提供的arecord进行录音,查看声卡外设
# arecord -l
**** List of CAPTURE Hardware Devices ****
card 0: AMLAUGESOUND [AML-AUGESOUND], device 0: TDM-A-dummy multicodec-0 []
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: AMLAUGESOUND [AML-AUGESOUND], device 1: TDM-B-dummy multicodec-1 []
Subdevices: 1/1
Subdevice #0: subdevice #0
card 0: AMLAUGESOUND [AML-AUGESOUND], device 3: PDM-dummy dummy-3 []
Subdevices: 1/1
Subdevice #0: subdevice #0
card 1: Loopback [Loopback], device 0: Loopback PCM [Loopback PCM]
Subdevices: 8/8
Subdevice #0: subdevice #0
Subdevice #1: subdevice #1
Subdevice #2: subdevice #2
Subdevice #3: subdevice #3
Subdevice #4: subdevice #4
Subdevice #5: subdevice #5
Subdevice #6: subdevice #6
Subdevice #7: subdevice #7
用arecord进行录音
arecord -Dhw:0,3 -c 8 -r 16000 -f S16_LE /tmp/xxx.wav
-D, --device=NAME select PCM by name 这里选择声卡0,设备3进行录音
-c, --channels=# channels 4个麦克风/8通道
-f, --format=FORMAT sample format (case insensitive)
-r, --rate=# sample rate
查看4个麦克风的录音数据
具体的录音数据分析待续