Usually before an artist uses another artist work they contact the company that the artist song is registered with ascap,bmi,sesac,etc or they get in touch with the artist directly and if a % for the usage of the artist song can't be worked out or the artist doesn't want his/her wok used then it can't be used.
one of the first two hip hop/rap artist to be sued for using an artist music with out permission were Sugar Hill gang by Bernard Edwards and Nile Rogers(of Chic)for using music from the song Good Times and Slick Rick for using music from the song Joy and pain by R&B icon Franky Beverly(of Maze featuring Franky Beverly),these two cases set off an avalanche of Rappers having to get permission from the copyright owners of the song(s)they wanted to use,in the case of the SWV track called Rain,the producer Brian A.Morgan outright did what he wanted to do with Portrait of Tracy and he got caught up and had to pay and in the process having to pay more than if he would have simply asked for permission and if given the OK a deal on %'s off the use of the song would have been properly made.
and yes Bassic83 you can put a rap to my video
