The Faces section analyses your photos to find faces and likenesses in them. It has two tabs: Faces and Similar photos.
A person, here, is a name given to a group of faces: it stays in this section. It is not an agent of the directory (see Agents), which attributions, provenance and exhibitions cite.
Privacy
Analysis (objects, text, faces, likeness) runs on this Mac, with Apple’s Vision framework. No image, face or fingerprint is sent anywhere: everything stays in the local library. You can erase it all at any time (see Erasing the analysis data).
Analysis never starts on its own: you start it, or ask for it to follow each folder import (Settings › Files › Run the analysis after import, off by default).
Analysing the library
Click Analyse the library (or, after a first analysis, Analyse new photos). Only the photos not analysed yet are processed. For each one, Catalog works on a reduced copy of the image (never on the original) and derives:
- the objects recognised and the text readable in the image, which become searchable (see Quick search); object names are those Vision provides, in English;
- the faces, each with a fingerprint that lets them be grouped;
- an image fingerprint, which lets you find the photos that look like it.
The analysis runs in the background, with its progress. You can stop it at any time: “Analysis stopped after n photos. It will resume where it stopped.” A photo whose file is missing or unreadable is counted separately and will be retried at the next analysis.
The status line tells you where you are: “n of m photos analysed · k faces”.
Naming people
After the analysis, Catalog offers suggestions: groups of at least two faces that look alike and are not yet assigned to anyone. “Grouping is approximate: nothing is named without you.”
- Name… on a suggestion creates a person with these faces.
- Named people appear at the top, with their number of photos.
Correcting a person
Click a person to see their faces. Choose those that are not them, then:
- New person with n faces… — to assign them to another person, whom you name;
- Detach n faces… — to put them back, after confirmation, among the suggestions.
Faces (at the top) goes back to the list.
Merging people
When the same person was named twice:
- Tick the people to bring together (at least two).
- Open the Merge n people menu and choose the one to keep (Keep “name”…).
- Confirm.
The faces of the others join the person kept, then those people are deleted. Undoing a merge means splitting by hand.
Renaming or deleting
Right-click a person: Rename… or Delete…. A deleted person gives their faces back to the suggestions; photos do not change.
Similar photos
The Similar photos tab uses the fingerprints computed by the analysis: run the analysis first.
- Photos close to a photo — choose a Reference photo in the list: Catalog shows the photos that look like it, from the closest to the least close (30 at most). The list offers at most 5,000 analysed photos.
- Likely duplicates — Find duplicates compares all the analysed photos and gathers into groups those that are nearly identical: crops, edits, exports of the same image. On a large library, the comparison takes time; you can stop it. Search again runs it again.
These likely duplicates differ from import duplicates (see Import a folder): the import recognises files with identical bytes, the analysis images that look alike.
Erasing the analysis data
These settings are in Settings › Faces & Analysis; Settings…, in the analysis banner of the Faces section, takes you there.
- Detect faces — on by default. Turned off, the analysis still recognises objects and text and computes the similarity fingerprint, without looking for faces. Photos already analysed are not done again: erase the analysis to start over.
- Erase… deletes from the library all analyses, fingerprints, faces and named people. Photos do not change. A new analysis starts from scratch.
Good to know
- The names given to people stay in the Faces section: they are not written into the files’ metadata nor added as tags.
- A photo added after the analysis is analysed only at the next Analyse new photos.
- A photo whose content changed (a new version at a re-import, a version restored) must be analysed again: its objects, text, similarity fingerprint and unnamed faces are erased. At the new analysis, the name given to a face goes to the face found again in the new version (the most alike, if alike enough); a name that does not find its face is removed, and the end of the analysis says so (“1 named face not found again in a changed file: name it again”). Writing the metadata into the file does not change its pixels: the analysis is kept.