将usb摄像头插入开发板，输入命令：cat /proc/asound/cards
可以看到有一个usb音频设备。
下载alsa-lib-1.1.7和alsa-utils-1.2.3两个库交叉编译alsa-lib-1.1.7./configure --host=aarch64-himix100-linux --prefix=./alsa-lib-1.1.7/buildout --enable-shared --disable-python
Make
Make install
交叉编译alsa-utils-1.2.3./configure --prefix=/root/Desktop/hisi/hi3559/thirdlib/alsa-utils-1.2.3/buildout --host=aarch64-himix100-linux --disable-alsamixer --with-curses=ncurses --disable-xmlto --disable-nls CFLAGS="-I /root/Desktop/hisi/hi3559/thirdlib/alsa-lib-1.1.7/buildout/include" LDFLAGS="-L /root/Desktop/hisi/hi3559/thirdlib/alsa-lib-1.1.7/buildout/lib -lasound"
录音测试通过编译出的arecord 命令录音测试。
arecord -D hw:0,0 -f S16_LE -r 44100 -t wav -c 1 -d 10 test.wav
