[FFmpeg-user] Using ffmpeg to remove commercials from video file

[Werner Robitza]

On Tue, Aug 20, 2013 at 12:13 PM, Jesper Lund Stocholm
<4a4553504552 at gmail.com> wrote:
> ffmpeg produces exactly identical files and console output (apart from the
> actual copying of stream that vary a little bit (I assume that is because
> of my machine doing other stuff as well)).
>
> Both files are 41:27 minutes in length.

I reproduced this now.

Here's the problem: When you use -ss before the input file, it skips
to the specified point, and then assumes this as being position
00:00:00 (i.e., the start of the file).
So, these are the same, because for ffmpeg the file starts at 0:

ffmpeg -ss 00:01:00 -i input -t 00:02:00 output
ffmpeg -ss 00:01:00 -i input -to 00:02:00 output

This however works and creates a file with 2 min length and 1 min
length, respectively:

ffmpeg -i input -ss 00:01:00 -t 00:02:00 output
ffmpeg -i input -ss 00:01:00 -to 00:02:00 output

Hope you understand what I mean.