<https://commons.wikimedia.org/wiki/File:Boat_movie.webm> a schema:Article ;
schema:about sdoc:M222222 ;
schema:isPartOf <https://commons.wikimedia.org/> .
should give a way to get from a filename to a MediaObject. But in WCQS there are no triples with the predicate schema:about and no objects of type schema:Article.
Is the description here outdated or is the triples missing in WCQS?
What is the recommended way to get a MediaObject if you have the filename? You can go the opposite way with schema:contentUrl by taking the last part of the URI and decode, but you cannot construct the contentURI from the filename.