how would we go about making a proof-of-unaltered videos? shall someone run an ICO for a start-up thickly dressed in a cloud of tags related to blockchain, web

how would we go about making a proof-of-unaltered videos? shall someone run an ICO for a start-up thickly dressed in a cloud of tags related to blockchain, web of trust, verifyable frames... Seriously, can any degree of trust be achieved short of hashing and signing every single frame by a trusted video sensor?