Canon EOS-1D X Mark III DSLR Camera (Body Only) - Manual (Page 439)

3.
Specify the part to be edited out.
Select either [ ] (Cut beginning) or [ ] (Cut end).
Press < > left or right to go back or forward one frame. Keep
pressing the multi-controller to fast rewind or fast forward frames. Each
turn of the <
> dial goes back or forward one frame.
After deciding which part to edit out, press < >. The portion indicated
by a line at the bottom of the screen will remain.
4.
Check the edited movie.
Select [ ] to play back the edited movie.
To change the edited part, go back to step 3.
To cancel the editing, press the < > button.
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