BigBlueButton Videos

How to mix BBB videos

This is the process allowing you to retrieve separate audio and video files, to build your own mix using FFMPEG.

BBB has a feature to record videoconferences but once the recording is complete, only a web interface to review the presentation, not a final video file.

Command Line process

1. Open your browser's Web Inspector / Developer Tools interface (F12) in a new tab

2. Load the video presentation page ex: https://<BBB DOMAIN>/playback/presentation/2.3/<SOME ID>

3. In the Developper Tools Network Panel, filter the Media assets, and find the WEBM resources, i.e. webcams.webm and deskshare.webm

4. Download the WEBM files

   $ wget https://<BBB DOMAIN>/<SOME ID>/deskshare/deskshare.webm
   $ wget https://<BBB DOMAIN>/<SOME ID>video/webcams.webm

5. Run FFMPEG to mix the files

   # Change the variable to cut some time at the beginning of the video
   # Default: None 
   # Format: hh:mm:ss.milli
   START_SEEK="0:0:00.000"
   ffmpeg -ss "$START_SEEK" -i deskshare.webm -ss  "$START_SEEK" -i webcams.webm  -c copy -map 0:v -map 1:a -y mixed-video-file.webm
   ls -lh mixed-video-file.webm