Trim objects in the Timeline in Motion
Trim an object’s timebar when you want to shorten or lengthen its duration in the Timeline. You can trim the beginning or end of the object by dragging from the left or right edge of the bar (the In and Out points). You can also trim an object by using menu commands and corresponding keyboard shortcuts. You can trim multiple objects simultaneously, and you can trim on the fly while your project is playing back.
Note: Video and audio objects cannot be trimmed to be longer than the duration of their source media. To extend a video or audio object beyond the duration of its source media, you must change the object’s End Condition to Loop, Ping Pong, or Hold in the object’s Properties Inspector. This limitation does not apply to other objects, such as still images, cameras, text, and shapes, all of which you can extend without restriction. You can also change the effective duration of a clip without adding or removing frames, by changing the clip’s playback speed. For more information on the Timing controls, see Intro to retiming media in the Motion Timeline.
When you trim a video object in the track area, Motion provides a visual representation of how much additional footage is available in the object’s source clip: a dimmed extension on either end of the bar indicating that unused frames exist in the source video clip. If you see no dimmed extensions when you trim a bar, there are no unused frames in the source clip. Consequently, you cannot lengthen the object (unless you change the object’s End Condition in the Properties Inspector for the clip).
Download this guide: PDF