How do you prevent an image from being downloaded from the web? You can’t!
Terence Eden knows this too, but it didn’t stop him from a very clever experiment. First, split the image into two in some fashion (he made every-other-line interlaced versions). Then…
Using JavaScript the first frame can be rendered onto a
<canvas>element for a millisecond, wiped, and then the second displayed. Repeat.
So if you screenshot it, you’ll only ever get half of it.
This isn’t a game anyone should ever try to play:
None of it matters of course. If you send pixels to a computer screen, they can be copied. It is possible to slow people down – but all it takes is for one person to work out how your scheme works and then it crumbles to dust.
But I still think it’s clever.