I would imagine that in the future video encoders will start to automatically include a cryptographic signature every X frames, which then players will become aware of and show an indicator for "original / modified" content.
It'd be too easy to fake, just replace the sensor in an approved camera with your own data feed. And that's assuming it wouldn't be somewhat trivial to dump keys from one or more cameras on the market to create a an easy tool or resignvideo.com... which is a massive assumption. As the movie industry has already seen, cryptography doesn't help you when you push out the keys to everyone. It'd be about as effective as D…
https://inis.iaea.org/collection/NCLCollectionStore/_Public/...
I remember visiting the MIT media lab when I was in college, they described the audio version of "invisible watermarking" - manipulating the source audio with a generated acoustic effect, similar to a doppler shift. The effect is not detected by the human ear, but signal analysis can translate it into binary metadata, such as a DRM signature.