My question would be, who does have "express knowledge of the key or the flickering at that moment in time" and are they trustworthy?
My question would be, who does have "express knowledge of the key or the flickering at that moment in time" and are they trustworthy?
That would be whoever owns the private key, no?
It's similar to any other private/public key scheme: it just serves to prove the signature was generated by the owner (here whoever owns the location at which the video is taken).
But I guess you could imagine multiple flickering patterns per location, with each pattern being owned by a different entity (an NGO + a governement + a private company for example), in essence doing a multi-sig of the video.