DroidCamX on Linux

I’ve been using DroidCamX to stream video from my phone onto my desktop. I can screenrecord my desktop and I don’t have to muck around with video editing; it’s all composed and done in one take.

I was recording my keyboard so I needed the lowest latency possible and using USB does much better than over WiFi. There are official native apps or you can (apparently) use other tools like VLC or ffmpeg. Here’s what I found to work for me:

• make sure USB debugging is enabled on your phone
• plug your phone in via USB
• start DroidCamX app on phone

• adb forward tcp:4747 tcp:4747
  

• make sure your phone screen is on. If it’s gone to sleep, you might not be able to connect

• curl 'http://127.0.0.1:4747/mjpegfeed?1920x1080' \
    | tee somefile.mp4 \
    | mpv - --no-cache --untimed --no-demuxer-thread
  

That last command deserves some explanation. We curl the 4747 port on our local machine, which is forwarded to the DroidCamX app via ADB. We use a query string to control the size of the video. You can find the available values for this by:

• opening the web interface for DroidCam
• picking from the available resolutions
• clicking the info button to see the URL to use (or you can guess what the URL would look like)

We pipe that into tee so we write the video to a file. It’s good to be able to see what you’re recording too so we pipe into mpv, which will show the video. The params we pass to mpv make it low latency (no caching/buffering) and tell it that it’s a stream so don’t confuse it with a standalone video file.

To stop recording, either ctrl+c the command or close mpv.