Embedded metadata
Embedded metadata is stored within the media resource's own structure and can describe different scopes such as a file, track, image or catalogue relationship.
Embedded metadata travels inside the media file. “Embedded” describes its storage relationship; it does not establish the meaning, correctness or precedence of every contained value.
One file can carry several scopes
| Example record | Intended scope |
|---|---|
| A track's language description | That particular stream |
| A movie title tag | The represented work or applicable target |
| An image orientation tag | The intended image presentation |
| A colour profile | Interpretation of image samples |
| A provider identifier | A catalogue reference for its specified entity |
A reader must interpret the record according to its format, field and target. Copying an album title into every track title would retain the words while changing their meaning.
Matroska tags can identify targets rather than describe only a single flat file record. Photo formats can similarly carry several metadata/resource structures with different responsibilities.
Container preservation is not the same as field use
A remux or export can retain coded media while changing its metadata carriage. Another conversion can preserve readable tags but change picture dimensions or colour representation.
An output needs records consistent with those changes. Keeping a pre-crop dimension or old orientation interpretation beside newly transformed pixels can misdescribe the result.
The orientation example shows why physically rotating a grid and retaining its old transform can cause a second rotation later.
Import creates another representation of the record
A library can read supported embedded fields into its database and then combine them with provider or user data. That database presentation is a new layer, not the original file rewritten in memory.
For Emby, distinguish the embedded record, the field the server reads and the displayed library value. Provenance and precedence explain how those layers can differ without assuming every possible embedded field has an Emby mapping.
A tag can remain present in the file while the library does not import it, maps it into a different field, or selects another candidate value. Editing the library display also need not change the source file.