# Face models

The shape-fixed SCRFD detectors and the ArcFace/MobileFaceNet embedder, in LFS. One copy, packaged
by every platform:

| Platform | How it ships | Where it lands |
|---|---|---|
| Android | `assemble-apk.sh` bundles them as APK assets; `android_main` unpacks on first launch | the shared user data directory |
| Arch | `PKGBUILD` installs them | `/usr/share/darkroom/models/` |

`library::face_models` searches the account's own directory, then the shared user directory, then
`$XDG_DATA_DIRS` — so a pair the user placed by hand always outranks the packaged one.

    scrfd_500m_640.onnx    2.5 MB   "Fast" in settings — what every library was indexed with until 0.12
    scrfd_2.5g_640.onnx    3.3 MB   "Balanced" — 14% more faces for 12% more time (faces.md §12.3)
    scrfd_10g_640.onnx      17 MB   "Thorough" — a further 12% for 3× the time
    arcface_mbf_b1.onnx     13 MB

Which detector runs is a per-device setting (`FaceSettings::detector`); all three are installed so
the choice exists on every platform. Each is its own `faces.model_id`, so changing it re-indexes.

**A clone without git-lfs gets a ~130-byte pointer where each model should be.** Both packagers check
for exactly that and refuse, rather than shipping the pointer and failing inside tract on the user's
machine. Fix it with `git lfs pull`.

These are not what InsightFace ships. They came from `buffalo_sc.zip`, `buffalo_m.zip`, `buffalo_l.zip`
and `buffalo_s.zip` on the InsightFace v0.7 release with their input dimensions pinned, because tract
cannot parse any of the graphs while they are dynamic:

    ./tools/fix-face-model-shapes.sh det_500m.onnx  models/face/scrfd_500m_640.onnx --input input.1=1,3,640,640
    ./tools/fix-face-model-shapes.sh det_2.5g.onnx  models/face/scrfd_2.5g_640.onnx --input input.1=1,3,640,640
    ./tools/fix-face-model-shapes.sh det_10g.onnx   models/face/scrfd_10g_640.onnx  --input input.1=1,3,640,640
    ./tools/fix-face-model-shapes.sh w600k_mbf.onnx models/face/arcface_mbf_b1.onnx --dim None=1

The weights carry a non-commercial research-only grant. They are here because this is a private
repository and self-installed builds; they come back out before anything is published, and the
restriction binds whoever uses the app, not only the project. docs/faces.md §2.2a is the decision.