简单记录一下 ffmpeg 获取 DirectShow 设备数据的方法。本文所述的方法主要是对应Windows平台的。（由于 ffmpeg 输出编码为 UTF-8, 所以这里使用 Git Bash ）
列出设备
$ ./ffmpeg -list_devices true -f dshow -i dummy
ffmpeg version 3.2.4 Copyright (c) 2000-2017 the FFmpeg developers
built with gcc 6.3.0 (GCC)
[dshow @ 00000000001c23c0] DirectShow video devices (some may be both video and audio devices)
[dshow @ 00000000001c23c0] "Integrated Webcam"
[dshow @ 00000000001c23c0] Alternative name "@device_pnp_\\?\usb#vid_0c45&pid_6448&mi_00#7&2645f9e4&0&0000#{65e8773d-8f56-11d0-a3b9-00a0c9223196}\global"
[dshow @ 00000000001c23c0] "screen-capture-recorder"
[dshow @ 00000000001c23c0] Alternative name "@device_sw_{860BB310-5D01-11D0-BD3B-00A0C911CE86}\{4EA69364-2C8A-4AE6-A561-56E4B5044439}"
[dshow @ 00000000001c23c0] DirectShow audio devices
[dshow @ 00000000001c23c0] "麦克风 (High Definition Audio 设备)"
[dshow @ 00000000001c23c0] Alternative name "@device_cm_{33D9A762-90C8-11D0-BD43-00A0C911CE86}\wave_{E26AD2BE-B335-41EC-BED5-40F982F21FF7}"
[dshow @ 00000000001c23c0] "virtual-audio-capturer"
[dshow @ 00000000001c23c0] Alternative name "@device_sw_{33D9A762-90C8-11D0-BD43-00A0C911CE86}\{8E146464-DB61-4309-AFA1-3578E927E935}"
dummy: Immediate exit requested
查看设备选项
video
$ ./ffmpeg -list_options true -f dshow -i video="Integrated Webcam"
ffmpeg version 3.2.4 Copyright (c) 2000-2017 the FFmpeg developers
built with gcc 6.3.0 (GCC)
[dshow @ 0000000000ea23e0] DirectShow video device options (from video devices)
[dshow @ 0000000000ea23e0] Pin "捕获" (alternative pin name "0")
[dshow @ 0000000000ea23e0] pixel_format=yuyv422 min s=640x480 fps=10 max s=640x480 fps=30
[dshow @ 0000000000ea23e0] pixel_format=yuyv422 min s=640x480 fps=10 max s=640x480 fps=30
[dshow @ 0000000000ea23e0] pixel_format=yuyv422 min s=352x288 fps=10 max s=352x288 fps=30
[dshow @ 0000000000ea23e0] pixel_format=yuyv422 min s=352x288 fps=10 max s=352x288 fps=30
[dshow @ 0000000000ea23e0] pixel_format=yuyv422 min s=320x240 fps=10 max s=320x240 fps=30
[dshow @ 0000000000ea23e0] pixel_format=yuyv422 min s=320x240 fps=10 max s=320x240 fps=30
[dshow @ 0000000000ea23e0] pixel_format=yuyv422 min s=176x144 fps=10 max s=176x144 fps=30
[dshow @ 0000000000ea23e0] pixel_format=yuyv422 min s=176x144 fps=10 max s=176x144 fps=30
[dshow @ 0000000000ea23e0] pixel_format=yuyv422 min s=160x120 fps=10 max s=160x120 fps=30
[dshow @ 0000000000ea23e0] pixel_format=yuyv422 min s=160x120 fps=10 max s=160x120 fps=30
[dshow @ 0000000000ea23e0] pixel_format=yuyv422 min s=1280x720 fps=11 max s=1280x720 fps=11
[dshow @ 0000000000ea23e0] pixel_format=yuyv422 min s=1280x720 fps=11 max s=1280x720 fps=11
[dshow @ 0000000000ea23e0] vcodec=mjpeg min s=1280x720 fps=10 max s=1280x720 fps=30
[dshow @ 0000000000ea23e0] vcodec=mjpeg min s=1280x720 fps=10 max s=1280x720 fps=30
video=Integrated Webcam: Immediate exit requested
audio
$ ./ffmpeg -list_options true -f dshow -i audio="麦克风 (High Definition Audio 设备)"
ffmpeg version 3.2.4 Copyright (c) 2000-2017 the FFmpeg developers
built with gcc 6.3.0 (GCC)
[dshow @ 00000000024d24a0] DirectShow audio only device options (from audio devices)
[dshow @ 00000000024d24a0] Pin "Capture" (alternative pin name "Capture")
[dshow @ 00000000024d24a0] min ch=1 bits=8 rate= 11025 max ch=2 bits=16 rate= 44100
Last message repeated 22 times
audio=麦克风 (High Definition Audio 设备): Immediate exit requested