title: How to add an external audio track to a video file using VLC or FFMPEG command line
body: <p>I want to add an audio.mp3 soundtrack to a soundless video.mp4 file using a bash script, what is the correct syntax of the "cvlc" "ffmpeg" command line ?</p>
  
  <p>I've recorded the video with VLC and --no-audio option so there is no settings such as bit rate or encoding that can be copied from the original video.</p>