Simple script using ffmpeg and v4l2loopback to pipe a video stream to a dummy webcam signal.
First, make sure the desired output exists:
ls /dev/video*
video0 is usually your webcam.
If not, try this:
sudo modprobe v4l2loopback
This should create '/dev/video1' and '/dev/video2' output streams. Use the latter. You can simply use the command as such:
. /path/to/repository/vtw file.mp4 /dev/video2
The -h flag is available as a quick reminder on the arguments' order. You can also create a soft link to invoke the script as a command:
ln -s ~/path/to/repo/vtw $PATH/vtw