What is metadata?
Any information that is included within a program, whether it is for a download or creating a disc, that is not the program itself. It is embedded within the digital file (as a download or when burned to disc). Examples are track IDs, start and stop IDs, ISRCs, UPCs, and CD Text information. One of the things that the mastering engineer is responsible for is understanding what these are and including all this information in a master.
What is an ISRC?
It stands for International Standard Recording Code. It is a number that is allocated to any publisher (record label, artist, or anybody that is owns a catalogue of music). It is registered in the USA with the RIAA (Recording Industry Association of America) and in Europe with GEMA (a performance rights organisation) . The code is a unique identifier that gets attached to every single piece of music (each song within a record would have its own ISRC code). Any time that the music is played over the air, downloaded or streamed, the identifier is logged. This is vital in the payment process .
What is a UPC?
It stands for Universal Product Code. Is a number assigned to a product. Traditionally it has been a physical item, such as a cereal box in a grocery store, which has a bar code (and correlating number) to scan at the checkout to identify what that product is. The same is true of CDs or DVDs. But they are also used to track downloads in some cases, so you should register and include it in your product.
What is QC?
This is what is known as Quality Check. Mastering is the final process before distribution. As a result, it is the mastering engineer’s job to make sure that there are absolutely no flaws in the program (a dropout or a click for example). The mastering engineer should give the client assurance that there is no problem with the audio.