Natanael

The lightfield part is harder do make in high DPI, but yes I had the exact same thought

You're gonna look like a CRT instead

Expensive and difficult to get high resolution (good quality precise microscopic mirrors). Apple went for higher DPI regular display because that's a far more well known engineering problem

That's the default, but you can block it in the command line configuration tool

Transparency logs like that are helpful to show when media was first seen / published

Merkle tree hashes exists for this purpose

Note that videos uses "keyframes" so you can't extract arbitrary frames in isolation, you need to pull multiple if the frame you're snapshotting isn't a keyframe itself

Look up transparency logs for that last part, it's already used for TLS certificates

It needs to focus on showing who published it, not the icon

Only RSA uses a function equivalent to encryption when producing signatures, and only when used in one specific scheme. Every other algorithm has a unique signing function.

Apple's scrapped on-device CSAM scanning was based on perceptual hashes.

The first collision demo breaking them showed up in hours with images that looked glitched. After just a week the newest demos produced flawless images with collisions against known perceptual hash values.

In theory you could create some ML-ish compact learning algorithm and use the compressed model as a perceptual hash, but I'm not convinced this can be secure enough unless it's allowed to be large enough, as in some % of the original's file size.

Browser controlled modal.

Do not show a checkmark by default! This is why cryptographers kept telling browsers to de-emphasize the lock icon on TLS (HTTPS) websites. You want to display the claimed author and if you're able to verify keypair authenticity too or not.