Metadata

Audio files can carry text about themselves — title, artist, comments, copyright, and for Broadcast Wave files a description and the recording's position on the timeline. The inspector shows this metadata and lets you edit it, for one file or many at once.

Metadata is stored differently in WAV, AIFF and CAF files, and different apps read different fields. If that's new to you, start with Audio metadata explained.

The inspector

Show or hide the inspector with the sidebar button in the toolbar. It shows the selected file — or a summary of all selected files — in sections:

File / N Files

Name, folder, format, duration, sample rate, bit depth, channels, size and dual-mono result. For several files: total duration and total size.

Loudness (EBU R128)

Measured loudness and, for Broadcast Wave files, the values stored in the file. See Loudness.

Info

The general text fields. The section title shows where they are stored: RIFF LIST INFO (WAV), AIFF text chunks or CAF info.

Broadcast Wave (bext)

WAV files only: description, originator, dates, coding history and the time reference.

Chunks, iXML, Comments, UMID

Read-only details for the curious: the list of chunks in the file, iXML production data, AIFF comments and the Broadcast Wave unique material identifier.

Edit and save

1. Select a file and type in a field. Changed fields are marked.
2. Click Save or press ⌘S. Revert throws your changes away.

If you select another file, rescan or close the folder with unsaved changes, the Media Manager asks whether to save them.

To remove a value, clear the field and save.

Edit many files at once

Select several files — ⌘-click, ⇧-click or ⌘A — and the inspector edits all of them together:

• A field that has the same value in all files shows that value.
• A field with different values shows Multiple values. Leave it alone and every file keeps its own value; type something and all files get the new value.
• Save writes all selected files. Files that can't be written are reported, the rest are saved.

Mixing WAV, AIFF and CAF

When the selection contains different formats, the inspector shows only the fields that every selected format can store. AIFF, for example, only has title, artist, comment and copyright, so a selection of WAV and AIFF files shows just those. Files that can't be edited at all (MP3, AAC, …) are counted in a note at the top.

WAV fields

Info (RIFF LIST INFO)

The classic WAV text fields. Each has a four-letter code inside the file — shown here because other apps and documentation often refer to them that way.

Under More fields: Technician (ITCH), Software (ISFT), Archival location (IARL), Keywords (IKEY), Medium (IMED) and Source form (ISRF). Other INFO fields found in the file are shown too.

ISRC code

The International Standard Recording Code (ISO 3901) identifies one specific recording (not the song itself), so each edit, remix or remaster gets its own code. It is always 12 characters: country code, registrant code, the last two digits of the year the code was assigned, and a five-digit number. It is often printed with hyphens, e.g. SE-ABC-26-00001, but the hyphens are not part of the code; enter it as SEABC2600001. Codes are issued by national ISRC agencies, often through your label or distributor.

A note on the name: in the original 1991 RIFF specification the ISRC field is called Source and was meant for the person or organization that supplied the material. Music software (for example the widely used TagLib library) uses it for the recording code, and that is how the Media Manager shows it. The EBU's own recommendation for Broadcast Wave files (EBU Tech 3352) stores the ISRC as XML in a separate axml chunk, which the Media Manager does not edit. If a distributor or broadcaster asks for the ISRC in a specific place, check their delivery specification.

INFO text is traditionally stored as Latin-1 (Western European characters). Text with other characters is stored as UTF-8; the inspector warns you, because some apps may show it incorrectly.

Broadcast Wave (bext)

Files recorded or bounced by Pro Tools, Logic Pro and field recorders usually have a Broadcast Wave chunk. Its fields have fixed maximum lengths; the inspector counts characters and warns when text will be shortened.

Broadcast Wave text is Latin-1 only; other characters are replaced by ? (the inspector warns first).

The time reference (where the recording starts on the timeline, in samples), the bext version and stored loudness are shown read-only. The time reference is never changed by the Media Manager — it is what puts a clip back in its place in Pro Tools.

Adding Broadcast Wave metadata

A plain WAV file without a bext chunk shows Add BWF (bext) Metadata. Click it to show the Broadcast Wave fields, fill them in and save — the file then becomes a Broadcast Wave file.

AIFF fields

AIFF has only a few text chunks:

Timestamped comments (COMT) are shown read-only. Some apps write an ID3 tag inside AIFF files; the inspector shows when one is present, but doesn't edit it yet.

CAF fields

CAF files store metadata as a list of named values (info chunk). The inspector offers Title, Artist, Album, Track number, Genre, Date created (recorded date), Comment, Copyright and Software (encoding application).

When only CAF files are selected you can also edit composer, lyricist, year, tempo, key signature and time signature.

Metadata and your DAW

• Pro Tools and broadcast tools use the Broadcast Wave fields: the description and originator to identify a file, and the time reference to place it on the timeline (Spot).
• Sample managers and libraries typically read the INFO fields (e.g. IART for artist).
• Which app reads which field varies — see who reads what.