I think this might be an actual use case for a blockchain like bitcoin. If someone takes an image or video and immediately embeds it into a bitcoin transaction, then at the very least that piece of raw media could be 100% verified as to the time of its creation or at least addition to the blockchain. If an event takes place at 3:52:04 pm and the image is uploaded at 3:52:25… at least you know no one had time to thoughtfully process what happened and create and upload an Ai fake. Or at least it would be MUCH more difficult. And if several images from different sources uploaded to the blockchain agree as to the events, that pretty much verifies it.