iMovie can analyze your Events (source video) for people and then tag this video so that you can easily find it later. Video is tagged according to the distance of the people in the shot (whether they are close up, in the medium distance, or far away). Video is also tagged by the number of people it contains: one person, two people, or more than two people (a group). (iMovie doesn’t recognize the identity of people.)
The ability to quickly find video containing images of people can facilitate creating projects. It is especially useful for creating trailers, whose templates require specific types of shots that feature your “cast.”
To analyze video for people during import:
You can choose to analyze your source video for people when you import it into iMovie from your video camera. The topics about importing video in the Import section of iMovie Help explain how: Import video from a USB camcorder or camera and Import video from a tape-based (FireWire-equipped) camcorder.
To analyze video for people after importing:
You can choose to have iMovie analyze your Events (source video) for people at any time after you import the video.
In the Event Library, click to select the Event you want to analyze.
Choose File > Analyze Video > People.
The File menu appears in a light gray bar across the top of your computer screen.
Choose “Stabilization and People” if you also want to analyze the Event for stabilization.
If the Event you selected is long, analyzing it can be time consuming; you might want to do it while you’re going to be away from your computer.
When analysis is complete, a People button appears below the Event browser to indicate that the Event has been analyzed for people.
Click the People button to see just the frames in the Event that include images of people.
You can also perform a more fine-tuned search for footage containing people using the Keyword Filtering pane.