Quickly Cut and Trim Any Video File

So you've got this video file that's taking up a lot of space. You've noticed it's 2-3 hours long but really you only need 20-30 minutes of it. This is going to show you how to chop it up.

Open the terminal and enter this command, changing (00:15:00 -t 00:45:23) to whatever length you're looking for and original.mp4 & output.mp4 as appropriate.

ffmpeg -acodec copy -vcodec copy -ss 00:15:00 -t 00:45:23 -i original.mp4 output.mp4

So that command above would take the original.mp4 file and create a smaller output.mp4 file consisting of original.mp4's 15 minute mark to 45 minute 23 mark.

If you prefer a GUI can also do this using AviDemux available from the software centre but from my experience this takes a longgg time (it needs to build the file - or something) whereas in the terminal it takes a matter of seconds.