The R to W data are protected by a Reed Solomon error correction code. Eight times interleaving is added to improve burst error correction. The R to W data can be in any of the following modes defined within the subcode channels. It is now possible to buy CD-G Karaoke versions of portable CD hifi audio equipment. They only need a television set to see the graphics and text which are the song lyrics and the owner has a portable self-contained Karaoke system.
User mode is intended for professional applications.
The meaning of the data is application specific.