It's not that bad.
> I found this API has a limitation it only suggests people in the photo who are in your FB friend list
> I found this API has a limitation it only suggests people in the photo who are in your FB friend list
Face.com did facial recognition on Facebook with no limits back in 2010.[2] Then Facebook bought them and killed the broad face recognition.[3]
There are other face recognition companies now, but they're keeping a lower profile about how broad their database is. Except for Findface[4] in Russia. They loaded up the entire photo database of Vcontact, a social network in Russia. 70% success in identifying random young people on the St. Petersburg metro.
[1] https://www.epic.org/privacy/facebook/Facebook-Biometric-Rul... [2] https://web.archive.org/web/20100701083622/http://face.com/ [3] https://web.archive.org/web/20120723211743/http://face.com/ [4] http://findface.ru/
To be concrete, my local supermarket and Amazon have my full name, and partial purchase information (the supermarket via a loyalty card). Both have ways to contact me with promotions. You don't think they'd like to know what I like on Facebook (if I did that) or what I search on Google that might suggest purchase intent?
I think they'd love that data, the platforms just make more money by only allowing them to target with it.
The only difference that I imagine exists is being able to search from the pool of "everyone" rather than "your friends", but that would make it less confident. In the law enforcement version, there would probably be a way to anchor the search to another individual just to improve accuracy to an acceptable level.