You can trim frames interactively. When you trim interactively, you scrub the Player to add frames to, or remove frames from, the in or out point.
To trim interactively:
In the Storyboard, select the shot you want to trim.
Click Editing in the main menu, and then click Edit to display the Edit menu.
Enable Trim.
In Trim mode, you see the first frame of the shot in the left viewer, and the last frame in the right viewer.
Do one of the following:
For greater control of the trim operation, middle-click as you drag to decrease the start frame by one frame or right-click to increase the offset by one frame.
To exit the Interactive Trim mode, do one of the following: