You guys might be interested in my startup. We are going to provide a copyright content registration service as well as a vetting service for 3rd parties to upload user posts which are then scanned against the registered content.
What I don't understand yet is why any of the content holds would help you by providing lots of useful metadata. It seems much more lucrative for them to find your violations and sue for more than they could have gotten from subscriptions and/or ads. Plus, if the site goes out of business fighting/paying, that's one less competitor for their own streaming service.
Played right, this could offset some lost ad revenue.