It would be nice to have a video format that incorporates cryptographic signatures, pubkeys,, A player can display these in a visual form, e.g. QR, Aztec,, before/after (in an intermission of?) the video proper. It would be neat if the signatures could handle some amount of distortion or compression of the video/audio, so that one signature could be used to verify a multitude of formats or insignificant transmission/streaming errors . . . maybe I could record it to my phone, and it would recognize that, yes, that video is what the author signed. Fantastic?