If we're just going to use the metadata about the movie, and not actual content data (nor even metadata about a specific media file, but rather only about the abstract "movie" itself, eg. as it ran in theaters or on TV independent of any content in someone's LMCE), then we could use the popular and complete Internet Movie Database (IMDb)
IMDb prohibits "framing"
any of their pages inside another page with someone else's logo (eg. "LMCE"), bu IMDb does allow linking
to any of its pages, even embedding its search form (and maybe just its search form submit URL API submitted by a custom form or widget in a client like LMCE). It looks like it's happy to let people include IMDb pages in separate apps, just as long as that page comes with the included IMDb logos and embedded ads
So if the "movie database" feature is just a standalone guide to movies in the world, and doesn't include links to get movie content that isn't allowed by the user's copyright clearance (eg. from some other user not authorized to distribute copies, like some Internet movie download site), then IMDb might be just the ticket (pun intended
. If someone has a specific implementation in mind, it looks like the IMDB corp is very approachable for questions about such use. There is most probably some use that would be good for LMCE that IMDb would allow along the lines it already explicitly mentions can be done without permission. If it's OK for IMDb ads to appear in the LMCE interface.
BTW, IMDb does offer a TV schedule
, even individualized for most movies (and many TV episodes)
, but individual titles' schedule listings are not complete
(I don't know whether the complete TV listings are complete). In any case, the reported listings would have to be presented complete in their return page (with ads, logos, etc). Probably IMDb would prohibit using just the data to schedule movies without showing in their complete/branded page, especially if that data is used to schedule recording movies (which, though legal for personal consumption without redistribution, is still controversial and probably pisses off Hollywood players like IMDb).
FWIW, I'd like to be able to use LMCE to search for movies, which results LMCE could link to those in my local collection if I have them. That looks a totally legit use of IMDb in LMCE.