> 503.03(a) Works-not originated by a human author.

> In order to be entitled to copyright registration, a work must be the product of human authorship. Works produced by mechanical processes or random selection without any contribution by a human author are not registrable.

Possibly nobody, but it depends how much input the program requires to generate the output. Just press a button and a song comes out -- can't be copyrighted. User has to enter a lot of parameters to generate output, user gets get copyright.