Specifically, the video is one of the Apple TV's screensaver images, taken at LAX (this one in particular [WARNING: high-def video link, ~267MB] [alternate YouTube version, thanks to Mark]).
It's not CGI. Apple used a variety of drones and helicopters to shoot the footage.
While the airspace around the airport is generally controlled (not restricted), there are a number of VFR flight routes that cross the airport. These can be seen on the Los Angeles Terminal Area Chart. In the case of this specific video, permission was presumably coordinated with ATC. As the video was taken down the middle of the airport, between the sets of runways, it's likely that taking it didn't interfere with air traffic; traffic arriving/departing LAX won't be flying there.
This tweet (with photos) just crossed my feed. @ethanklapper: Today was special. Chartered a helicopter and flew above LAX at 2,500 feet. Took 500 pictures in an hour. Can’t wait to share more!
I imagine a similar process was used for this video.