[milansuk]

This could work from buyer/client side. If I want to buy image, I will check it with some service to be sure that I don't pay to pirate(newer&lightly changed image). But what If buyer doesn't use it?

I don't see the way how this could be implemented to blockchain. If every blockchain node downloaded and compared all images It would create massive bandwith and need for cpu/gpu power. Or am I missing something?

[rglullis]

You are right, I don't see this going to the blockchain as well. But I am thinking of a service that runs outside of it, whose main purpose would be to provide (1) some legal support in case you want to file a copyright violation claim and (2) the basis for a reputation system.