Trim videos without re-encoding

Today I learned that FFmpeg is the easiest (only?) way to trim/cut a video without re-encoding it.

You can specify a start and stop time like so:

ffmpeg -i input.mp4 -ss 00:01:30.000 -to 00:04:05.000 -c copy output.mp4

The key is the -c copy parameter which will just copy the data frames for operations where they don’t need to be modified. This is nice because it’s way faster than decoding and re-encoding and you don’t have any loss in quality if you’re not working with a raw format.

It also works for removing/replacing the audio of a video. This ultimate guide is really handy.