Fill missing album artists from a reviewed track credit¶

Uses Filter and Tag → Tag / Format Value

Works on Copied ordinary local files with a reviewed primary artist

Time About 5 minutes

Undo Recorded applied changes in the current desktop session; keep originals

The problem¶

Your album has ARTIST, but no ALBUMARTIST. A player may group that album using Album Artist. Copying each track's artist is suitable only when that is the intended album-level credit. A compilation with a different artist per track usually needs one deliberately chosen common album artist instead.

This recipe uses the first Artist value as that primary credit. It does not decide who the album artist ought to be. Existing Album Artist values are excluded from the main selection.

The tables use JSON lists to show distinct values, including empty strings. Absent means no field. They describe core metadata snapshots; native formats can normalize empty values differently when saved.

ID	`ARTIST` before	`ALBUMARTIST` before	Pass main filter?	`ALBUMARTIST` after applying to matching rows
A	`["Juniper Vale"]`	Absent	Yes	`["Juniper Vale"]`
B	`["Juniper Vale"]`	`["Harbour Collective"]`	No	`["Harbour Collective"]`
C	`["Juniper Vale","Mira Solberg"]`	Absent	Yes	`["Juniper Vale"]`
D	Absent	Absent	No	Absent
E	`[""]`	Absent	Yes	Absent
F	`["Juniper Vale"]`	`[""]`	No	`[""]`
G	`[" "]`	Absent	Yes	`[" "]`
H	`["","Mira Solberg"]`	Absent	Yes	Absent

E, G and H pass a presence test but do not supply a useful primary credit. Stop at the preview and fix or exclude those files. C intentionally uses only the first artist; preserve a joint credit with the list-aware variation below instead.

The solution¶

Work on a copied album. Save or discard pending edits before opening the converter. Inspect its track artists and decide whether one primary artist per file is the right album-level policy. For a compilation, enter the common reviewed Album Artist through the tag panel and save instead.
Choose Edit → Unselect all, show the filter and enter:
```
ALBUMARTIST MISSING AND ARTIST PRESENT
```
Wait for filtering, or press Enter when auto-apply is disabled. MISSING means no values; a present empty string is not missing. Filtering can inspect pending metadata, which is another reason to resolve edits first. 3. Select only the intended visible practice rows. A filter does not clear earlier hidden selections. Exclude empty or whitespace-only artists and credits that should not become an album artist. 4. Choose Convert → Tag → Tag…, enter ALBUMARTIST in Field, and use:
```
$if2(%albumartist%,%artist%)
```
Inspect the preview. %artist% is the first Artist value. An empty result is a reason to stop and investigate, not a request to guess a name.
Apply only the reviewed practice selection. This converter writes immediately; it does not leave the result waiting for Save tags. Reload and inspect the saved fields before processing the rest of the album.

The same format string can be a Format Value action with Field ALBUMARTIST. A quick action's Apply action also writes immediately; it is not the converter's preview. Test the definition on a copy before putting it into a larger group.

How it works¶

The filter chooses files with no Album Artist values and at least one Artist value. PRESENT does not require useful nonempty text; E and G demonstrate why a preview and a human credit decision are still required.

$if2 returns its first nonempty argument. It reads Album Artist first and uses Artist when that first text is empty. Ordinary placeholders read the first value, so this is a primary-credit rule, not a copy-every-artist rule. If the first Artist value is empty, a later nonempty Artist is not chosen automatically, as H shows. Spaces are nonempty text. The single-value Format Value result is not implicitly trimmed.

The filter is what protects existing lists here. Running the scalar formula on every file could reduce a multi-value Album Artist to its first value. Do not treat $if2 as an exact whole-field/list preservation operation.

Variations¶

Preserve all credited Artist values¶

If the album genuinely has a joint credit, keep the same reviewed missing-field selection but preview this expression:

$meta_sep(ARTIST,$char(92)$char(92))

$meta_sep joins every Artist value with two backslashes. Format Value splits that result into separate metadata values, trims each part, and drops empty parts when the separator is present. Without it, a nonempty single result retains its spaces. It is not a universal lossless copy of arbitrary text containing literal double-backslash pairs.

`ARTIST` values	Resulting `ALBUMARTIST` values
`["Juniper Vale","Mira Solberg"]`	`["Juniper Vale","Mira Solberg"]`
`[" Juniper Vale ","", " Mira Solberg "]`	`["Juniper Vale","Mira Solberg"]`
`[""]`	Absent
`[" "]`	`[" "]`

Include blank-looking existing fields¶

A field containing "" or spaces is present. Inspect its full value list in Extended tags before changing the filter or clearing it. A test for an empty value can also match a list that has useful other values. Review those lists rather than applying a broader query to the whole library.

Recover from the wrong credit¶

Read Edit → Undo …'s operation label and count in the current desktop session. History is not a permanent backup and may cover a larger batch than the current selection. Inspect any pending edits afterward; saving them can replace the restored values. Keep copies for recovery beyond that session.