Their "open" video material: http://podcasts.ox.ac.uk/ A somewhat small part is Creative Commons, but most proprietary. Despite the name "podcasts", they do contain video, it is just a relic.
http://podcasts.ox.ac.uk/open contains actual Creative Commons only it seems.
Talks: https://talks.ox.ac.uk/. Mathematical, Physical and Life Sciences (MPLS) subset: https://talks.ox.ac.uk/talks/department/id/oxpoints:23232639