It does both. Each image and then neighbors. Usually you scan photos that are printed in related-date order. So it does look at neighboring photos to date.

You can tag faces and add a birthdate; so sort of. Like it'll recognize a birthday party photo and then if it's tagged with that person in the picture, it will date it on their birthday.

I think this method could do well with handwritten journal entries and artists’ sketchbooks, that add another dimension of information.