Tutorial: How to Trim a Video without Transcoding using Avidemux

in #videography8 years ago (edited)

Video Demo


Overview

  • Download and install Avidemux
  • Open the video you want to trim in Avidemux
  • Select and delete parts that you want removed
  • Save as a new video
  • Review the trimmed video
  • Conclusion

Download and install Avidemux

Avidemux is a free, open source, and cross platform (Windows, Mac, Linux) video editing app. It is available to download here.

Open the video you want to trim in Avidemux

In the video demo above, I opened the short film Big Buck Bunny in Avidemux to trim off the beginning and end. I got the 1080p h.264/aac mp4 version of Big Buck Bunny from here.

Select and delete parts that you want removed

  • To trim the beginning, scrub the video near where you want to make the initial cut
  • Use the "Previous Intra Frame" button and "Next Intra Frame" button to find an I‑frame to cut on
  • Press the "Set Marker B" button and Avidemux will automatically "Set Marker A" to the beginning of the video
  • Press "Delete" and it will remove everything between Marker A and Marker B which would be the beginning of the video
  • To trim the end, scrub the video near where you want to make the next cut
  • Again, use the "Previous Intra Frame" button and "Next Intra Frame" button to find an I‑frame to cut on
  • This time, press the "Set Marker A" button and Avidemux will automatically "Set Marker B" to the end of the video
  • Press "Delete" and it will remove everything between Marker A and Marker B which would be the end of the video

Save as a new video

  • Make sure "Video Output" is set to "Copy"
  • Make sure "Audio Output" is set to "Copy"
  • Under "Output Format" choose "MP4v2 Muxer". I suppose you can choose a different "Output Format", but for compatibility's sake, I like MP4v2 which most modern devices can play.
  • Press "Save"
  • Give the new video a unique name, so you don't overwrite the original

Review the trimmed video

  • Open the newly trimmed video in your favorite media player. I prefer VLC.
  • Check to make sure it's the way you wanted it

Conclusion

I like using this method when I download music videos from YouTube. Sometimes, the videos have really long intros and outros that I want to trim off. Then, I randomly play the trimmed videos on my Kodi HTPC to create my own custom pseudo music video channel that is free from ads and overly long intros/outros.

Pros

  • Keeps the original quality. Doesn't suffer from generation loss
  • Since you're doing a lossless copy of just the parts you want, it's much faster creating the trimmed video without having to transcode

Cons

  • Since you have to cut on an I-frame, you can't select an exact timecode to cut on
  • It would be faster if you could just select the part of the video you want and invert the selection to delete, but Avidemux doesn't have that option

Source

This tutorial originally appears on my personal site here.