There’s a small fee for formal registration. But generally you can establish copyright simply by publishing/performing. Particularly if its formally documented and dated in some fashion. The old trick was to mail a copy to yourself and keep the copy in the sealed post marked envelope.
Its always better to file. But technically you can establish a claim for free. OR manufacture a false history after the fact. Best ROI would be from using your program to generate songs just close enough to valuable recent ones to sue over. Then falsify your high school Ska band throwing them up on Myspace 20 years ago.
