Copyright only protects against copying. Independently coming up with the same thing is not copyright infringement.
"The scrambled file still has the copyright Colour because it came from the copyrighted input file. It doesn't matter that it looks like, or maybe even is bit-for-bit identical with, some other file that you could get from a random number generator. It happens that you didn't get it from a random number generator. You got it from copyrighted material; it is copyrighted. The randomly-generated file, even if bit-for-bit identical, would have a different Colour."
seems like in practice it would boil down to whose lawyers are better which is just a proxy for which party has more money.