Canon EOS 6D Instruction Manual page 256

X Editing a Movie's First and Last Scenes
Since the editing is performed in approx. 1-sec. increments (position
indicated by [
differ from the position you specified.
If the card does not have enough free space, [New file] will not be
available.
When the battery level is low, editing the movie is not possible. Use a
fully-charged battery.
256
Save the edited movie.
4
Select [W], then press <0>.
The save screen will appear.
To save it as a new movie, select
[New file]. To save it and overwrite
the original movie file, select
[Overwrite]. Then press <0>.
On the confirmation screen, select
[OK], then press <0> to save the
edited movie and return to the movie
playback screen.
]), the actual position where the movie is edited may