What is metadata?

Metadata records information about a media resource or the work it represents, allowing a library to identify, describe, organize and present it.

A movie file can have a technical identity as bytes and streams, while the film has a title, creators and release history. A media library needs useful information about both.

Metadata records that information. It lets a library show something more meaningful than a list of file paths and lets playback decisions use properties of the actual resource.

The described thing matters

Consider an invented film called The Station and one encoded copy:

Fact What it describes
Display title and cast The film/work
Provider's title identifier A catalogue record for that work
Resolution and video codec A particular media representation
Audio language and track title A stream within that representation
Local path and file size A stored resource
Artwork's dimensions A related image resource

These scopes should not be collapsed into one universal item identifier. Two editions of a film can share descriptive facts while having different timelines and technical properties.

Records make library actions possible

Descriptive metadata supports browsing by title, people, dates or other meaningful properties. Technical metadata helps characterize the selected file and its streams.

Identification connects the resource with an intended work or catalogue entity. Metadata can come from embedded records, sidecars, external providers or user edits.

The record's meaning depends on its field and vocabulary. A language code, an orientation tag and a release date are not interchangeable strings merely because all can be serialized as text.

In Emby, library setup establishes the content context, while the Metadata Manager exposes descriptive editing. Those functions rely on different kinds of information being attached to the correct resource or library entity.

A correction changes a particular layer

Changing a display title does not rename the spoken dialogue inside the video. Editing a language label does not translate an audio track. Correcting an orientation description can change how an image is displayed without rotating its stored samples.

Likewise, replacing a media file can change its technical properties while the film's title remains valid. The useful question is which entity and field an operation updates.

Provenance records where values came from; precedence explains how candidate values can become the currently displayed record.

See Also

References