The Pre-Master Compact Disc (PMCD) was developed by Sonic Solutions and Sony and is specified in the Red Book
as a replication master. A PMCD is a mastering format that contains the ISRC codes, International Standard Recording Code (ISRC), for processing and PQ codes in the credits for authentication. As a result, PMCDs can only be created by a few CD recorders, and before it is used to create the Glass master, it can be played on regular CD players. Some CD manufacturers require printouts of the PQ codes in addition to the PMCD for the authenticity of the content.