Trimming Clips
Trim in the Preview window
You can preview any clip and set new In and Out points for it before adding it to the Timeline or Sceneline. You might, for example, preview your clips to determine their quality and trim unusable parts before arranging them. You can preview and trim clips in the Preview window.
- A. Zoom control B. Clip in point C. Current time D. Current-time indicator
- E. Playback controls F. Clip out point G. Clip duration
Trim in the Timeline
You can remove or regain trimmed frames from either end of a clip by dragging the clip’s edge in the Timeline. To help you locate the precise frame you want, the Monitor panel displays the frame at the changing In or Out point of the clip as you drag. If another clip is adjacent to the edge you’re trimming, the Monitor panel displays the frames of both clips side by side. The frame on the left (the Out point) is earlier in time, and the frame on the right (the In point) is later in time. Subsequent clips, as well as blocks of empty space, in the Timeline shift as you drag the clip’s edge.
A tool tip displays the number of frames you are trimming as you trim them. This window displays a negative value if you drag the clip’s edge toward the beginning of the movie, and a positive number if you drag toward the end of the movie. You can tell whether you have trimmed a clip by looking for a small gray triangle in the top corner at either end of the clip in the Timeline. The triangle indicates you have not trimmed that edge.
For linked clips (video that includes a soundtrack), dragging the edge of one clip changes the In or Out points of both clips. Sometimes you want to trim linked clips independently to create split edits (also known as L‑cuts and J‑cuts). Pressing Alt when you trim allows you to set the In and Out points of the video and audio separately.
Split clips
You might want to apply different effects to different parts of a clip; for example, to speed up the first part but leave the second part at normal speed. To do this, you cut a clip into separate pieces, and then apply effects and transitions to those pieces. You can split a clip in a movie by using the Split Clip tool 
in the Monitor panel. It cuts one or more selected clips at the current‑time indicator.
Splitting a clip divides it into two parts, creating a new and separate instance of the original clip. If the clip is linked to another clip, a new instance of the linked clip is created as well. The two resulting clips, when combined, represent the original clip. The resulting clips are full versions of the original clip, but with the In or Out points changed to match the location marked by the tool. You can select and delete these clips.
