Per the 2026-06-08 deep-research synthesis (docs/synthid-robust-identity-
research-2026-06-08.md), the entire ArcFace-class identity-adapter ecosystem
for SDXL is blocked from commercial use by InsightFace's non-commercial model
packs (antelopev2 / buffalo_l). No commercial-safe ArcFace-grade identity
stack exists today. The user explicitly opted into shipping a non-commercial
restore path (research / personal use; raiw.cc must NOT install the extra).
Architectural choice: InstantID over PhotoMaker-V2 as the default.
- PhotoMaker-V2 (CLIP+ArcFace dual encoder, txt2img only): documented upstream
identity drift on Asian male faces, visually confirmed in our cert sweep
(tatsunari rendered as a generic woman; group photo collapsed into a
patchwork).
- InstantID (ArcFace cross-attention + landmark ControlNet): semantic
identity branch + spatial weak landmark control, decoupled. Per InstantID
paper (arXiv:2401.07519) and the research report, stronger identity fidelity
on single portraits. Critically: NO original face pixels enter the diffusion
(ArcFace embedding is semantic, landmark stick figure is pure geometry), so
SynthID is not transported.
Implementation:
- New `src/remove_ai_watermarks/instantid_restore.py` mirrors the
`photomaker_restore.py` shape (lazy singletons for pipeline + FaceAnalysis,
per-face crop + _composite_faces from photomaker_restore). Loads the
InstantID community pipeline via `DiffusionPipeline.from_pretrained(
custom_pipeline="pipeline_stable_diffusion_xl_instantid")` -- no upstream
Python package needed; diffusers fetches the file from its community
examples.
- New `instantid` extra in pyproject (insightface + onnxruntime +
huggingface-hub). NON-COMMERCIAL block in the comment explains why.
- CLI: `--restore-faces-method [instantid|photomaker]`, default `instantid`.
Both methods explicitly labeled NON-COMMERCIAL in the help text.
- Engine: dispatch on `restore_faces_method` to either
`_restore_faces_instantid` or `_restore_faces_photomaker`.
- 9 control-flow tests for InstantID without model download (mirror the
photomaker_restore.py test pattern + draw_kps helper checks). 587/587 pass.
Diffusers-0.38 compat verified by upstream code inspection: the InstantID
pipeline inherits from `StableDiffusionXLControlNetPipeline`, uses only
public diffusers APIs (`encode_prompt`, `prepare_image`, `prepare_latents`,
`get_guidance_scale_embedding`), uses legacy attention processor API which
diffusers preserves for backward compat. No PhotoMaker-V1-style internal
text_encoder access. End-to-end execution will be validated by the Modal
cert sweep in the next step.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
