Ethical: if the input image has a direct and meaningful effect on the derivative output, then I think attribution is the right thing to do. But then again, you'

Ethical: if the input image has a direct and meaningful effect on the derivative output, then I think attribution is the right thing to do. But then again, you'll likely attract negative attention as you never asked for permission. The interesting question to me is how relevant these input images will be in the future. I've already seen demos where people whom cannot draw for shit paint some sloppy strokes in MS Paint in order to hint AI in the correct direction. This is how a kid's drawing transforms into a Hollywood-class rendered scene. If this is the future direction, we might not need "fancy" input images by human artists, and the question becomes less relevant. The very concept of "human authorship" is going to be challenged. It's not as simple as prompt->image. People are combining AI with post processing, independently generated layers, it's all going to be a hybrid mess.