title: ffmpeg - combine videos into one wide video
body: <p>I have 3 video of 1920x1080. They are all the same length/codec. I'd like to combine them (not concatenate), so that the result is one video of 5760x1080.</p>
  
  <p>Can someone explain to me how to do this in ffmpeg (or another free application)?</p>
  
  <p>Thanks!</p>