My understanding, in short:
One of the fundamental tenents of copyright is that it protects only the form in which ideas and information are expressed
(hey, here's a US authority even: Baker v Selden (1880) 101 US 99
- yes, everyone uses it). In other words, copyright does not protect ideas as such, only the form of expression.
So ... if you read a recently published book and proceed to create a painting, say, based on a chapter in that book, it would be pretty hard to say that's copyright infringement (unless you ripped off an illustration in the book).
I'll leave it at that. I'm in Australia and different countries have different IP regimes.
NB. this ain't legal advice