> You cannot use a copyrighted image to produce derivatives without obtaining authorisation from the copyright owner of the original work.
You can produce derivatives as long as the derivative doesn't contain anything substantially similar to the expression in the original work [1]:
> To win a claim of copyright infringement in civil or criminal court, a plaintiff must show he or she owns a valid copyright, the defendant actually copied the work, and the level of copying amounts to misappropriation.
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> In the first context, it refers to that level of similarity sufficient to prove that copying has occurred, once access has been demonstrated.
No similarity means no copying means no infringement. Simply using someone else's work is not infringement.
An AI model can produce outputs similar to the original works, but that's almost always if not always because the prompt contains a reference to an author, an existing work, or a characteristic/style strongly associated with an author or an existing work. So there is infringement, but the most of the liability should belong to the person who chose the prompt, assuming the model creator responds to notifications of such situations from the relevant copyright holders by preventing the model from responding to prompts. Think DMCA.
[1] https://en.wikipedia.org/wiki/Substantial_similarity#Substan...