Video files take up a lot of space on hard disks, so it can be helpful to get rid of video footage you don’t use.
You can quickly delete all the video in an Event that you haven’t used in a project, haven’t marked as “favorite,” or haven’t marked with a keyword. Before you begin, make sure you’ve marked as “favorite” or marked with a keyword any video that you want to keep but haven’t used in any of your video projects.
To delete all the excess video in an Event:
In the Event Library, select one or more Events.
To select more than one Event at a time, press Command as you click Event names.
Choose File > Space Saver.
The File menu appears in a light gray bar across the top of your computer screen.
Select any of the following:
To reject all of the video that hasn’t been added to an iMovie project, select “Not added to any project.”
To reject all of the video that you haven’t marked as “favorite,” select “Not marked as Favorite.”
To reject all of the video that you haven’t marked with a keyword, select “Not marked with a keyword.”
Click “Reject and Review.”
The view changes to show only the rejected clips in the selected Events.
Review the clips in the Event browser to make sure that you haven’t accidentally rejected some clips that you want to keep.
If you want to keep some of the clips that have been rejected, select them, and then click the Unmark button (shown below) to remove the rejected status. When you do this, they disappear from the view.
When the clips left in the view are just those you want to delete, click “Move Rejected to Trash” (A, below) in the upper-right corner of the Rejected Clips window.
Click the “Move to Trash” button in the dialog that appears.
To delete the clips permanently from your hard disk and free up space, click the desktop outside of the iMovie window to see the Finder menus at the top of your computer screen, and then choose Finder > Empty Trash.
The clips are permanently deleted.
To bring the remaining clips back into view, click Hide Rejected (B, above) in the upper-right corner of the Rejected Clips window, or choose Favorites Only, “Favorites and Unmarked,” or All Clips from the Show pop-up menu below the Event Library.