XO Wave: Metadata

(ISRC, UPC, ID3, and CD Text)

XO Wave uses non-audio information in various ways. It can gather this data automatically from imported files, iTunes, and other sources, or you can enter it into XO Wave directly. This document explains how this information is collected, edited and used. Note that this metadata is most useful with XO Wave Pro, which allows exporting it to QuickTime formats and CDs in the form of ISRC (International Standard Recording Code), UPC (Universal Product Code, also called UCC-12), and CD Text data. If you want to use CD Text, you should be sure to use XO Wave 0.19.2b or later, since CD Text support improved in that release.

The links in the sidebar give an excellent introduction to various kinds of metadata, and why they are increasing important for artists.

Importing and Editing ID3 and Other Tags

When you import files that have ID3 tags or other metadata, XO Wave automatically imports whatever metadata it can read. This data may represent the song's title, author and arranger credits, or other information. If you import from iTunes, information from your iTunes library can be imported as well. Note that due to limitations in QuickTime, some data that uses non-ASCII characters may not be correctly imported from MP3 files; however, data stored in your iTunes Library is usually read correctly, so if your MP3 files are imported from iTunes, this should not be a problem.

Once a file has been imported, the data is associated with the file and can be edited by selecting View/Edit File Metadata from the Edit window's Region Bin Menu.

The Session Metadata Editor has three separate tabs which allow editing the session's properties, used when exporting the session and burning CDs. All three tabs are shown side by side.

UPCs and ISRCs

UPCs (or Universal Product Codes) are numbers which can be used to uniquely identify each product sold or transferred in the global marketplace. If you plan on selling a CD, most stores and distributors require a barcode, which is generated from your CD's UPC. Many commercial releases also embed this information in the CDs themselves (as part of the Q subcode), which can be done in XO Wave Pro simply by setting the appropriate value in the Session Metadata window, as described below, before creating your CD Master.

ISRC data is used to uniquely identify each recording. CDs allow a unique ISRC to be assigned to each track, which allows the usage of recordings to be monitored and tracked. For example, a radio station might use ISRCs for tracking royalty payments on all the music it plays. Because all major online music retailers, including the iTunes music store, require ISRCs for each track they sell electronically, there is no reason not to also include the ISRCs on your CD.

An ISRC is a 12-digit code divided into four parts: the first two digits identify the country of origin of the ISRC. The next three identify the registrant of the ISRC. A registrant may be an entity such as a record label or distributer. The next two identify the year in which the ISRC was assigned. For example, if an ISRC is assigned in 2007, these digits will be "07". The last five digits are a designation code, chosen by the registrant, which uniquely identifies the recording.

In XO Wave, you can assign an ISRC to each track of a CD by editing the ISRC codes in the Memory Locations Manager. If each track will have similar ISRC codes, you may want to edit the Default ISRC field in the Session Metadata Editor. Additionally, if your ISRCs will be sequential, you may want to set the Auto Increments ISRCs checkbox, so that ISRCs will be assigned automatically, in sequential order starting with the Default ISRC, to each track on your CD.

The default ISRC is created each time you create a new session in the following way: the registrant is determined based on your default registrant preferences settings. (If you frequently assign the same registrant codes, you may change this setting in the Preferences window.) The year code is derived from the current date and the designation code is initially set to all zeros. The country is currently determined by the country your operating system reports, typically determined from the time zone setting; however, this may produce an incorrect country code (in particular, it may produce one that does not correspond to your registrant), so take care that your country code is the one corresponding to the authority who issued your registrant code. In a future release, we plan to make the default country a preference, just like registrant codes, which should reduce the risk of such errors.

ISRC and UPC data is stored in the CD's Q subcode, along with timing information, and thus will not interfere with the audio playback of your CD. If you include CD Text (described below), the ISRC and UPC data will be stored there as well.

The Session Metadata Window allows you to export your UPC codes as PNG and EPS barcode graphics for use on your CD packaging. Note that at this time, this is still an experimental feature, so you should verify that the barcodes are correct before using them.

Session Metadata

The session as a whole stores some additional metadata, such as artist and song title information. This information is used when exporting to QuickTime and to create CD Text when creating a CD Master. Because almost all file formats are exported using QuickTime, most formats will carry at least some of this information. Note that, at this time, session metadata is not exported to MP3 files.

CD Text

CD Text data may be embedded on the CD's R and W subcodes, so, like UPC and ISRC data, CD Text does not affect the audio playback of your CD. Some CD players can read CD Text data and use it to display song information such as songwriter and track name. Information is stored in up to 8 blocks, each of which may be associated with a wide range of languages, including "None", which indicates that the given block is not associated with any particular Language. Unfortunately, the CD Text standard supports only two-character encodings (ASCII and ISO Latin Modified 1), which in practice means that it cannot be used for non-Latin languages, such as Japanese.

Each block of CD Text is created by taking the session and CD track metadata, converting it to the appropriate encoding (which may mean removing unsupported characters, such as Chinese characters), and tagging it with a language. Creating more blocks with different languages and (especially) encodings may improve the number of players which can read and display the CD Text information. By default, new sessions are created with support for an unassigned language, and English, in both ASCII and ISO Latin Modified 1 character encodings, but this can be changed in the Preferences window.

To help you figure out just what will be shown on players which support CD Text in either ASCII or ISO Latin Modified 1, many metadata text fields show their values in Unicode (the universal encoding native to XO Wave), and both the standard CD Text encodings.

CD Tracks

When you use the Auto Create... feature of the Memory Locations Manger to create CD Tracks, the CD Tracks will automatically be created with metadata which you can edit or use as-is. If you selected Automatically create Sequential ISRCs in the Session Metadata window, the ISRCs will be sequential and not editable. If you wish to edit individual ISRCs, be sure to uncheck this box.

Burning CDs with ISRC, UPC, and CD Text Data

When you burn CDs, the data from your session and CD Tracks will automatically be made available for burning if you are running XO Wave Pro, and will be burned to the disc unless you deselect the appropriate the options in the Burn CD From Master Wizard.

Note that you must setup your metadata before creating your master, or it will not be stored in your master and, therefore, not be burned to your disc.

Limitations

There are several limitations associated with burning metadata with XO Wave:

• For CD Text, not all accented characters are supported. This is due to a limitation in Mac OS X.
• For greatest compatibility, CD Text should be written to both the lead-in area and the program area. Currently, Mac OS X only supports writing CD Text in the lead-in area, so some CD Text players might not be able to read the CD Text on the disc. At one point there were reports of some disks having this problem, however the issue turned out to be caused by a different bug which Apple has since addressed. In practice, we believe that all CD Text players should be able to read CD Text from discs burned with XO Wave and a reasonably current version of Mac OS X.