When I add a movie or other video to iTunes, it appears that iTunes selects a video frame from somewhere near the beginning of the video file as the default cover art — and most of the time this is a terrible choice.
Many of the shows and movies in my collection have an opening sequence containing frames where a title is plainly shown (e.g. "Dr. Seuss' How the Grinch Stole Christmas!"), or at least there's some scene in the video which is distinct & identifiable, a scene I would clearly recognize when scrolling through my collection with the Cover Flow view.
I'd like to specify such a distinct frame, from an arbitrary point in a video, as a video's cover art. I expected a slider somewhere to seek through a video and find just the right spot to use as cover, but I didn't find such functionality.
How does iTunes determine which frame to select for the cover art from a video?
Is there a way to tell iTunes to use a different video frame as the cover art?
Failing that, what is a good alternative?