---
license: apache-2.0

tags:
  - image-classification
  - multi-label-classification
  - booru
  - tagger
  - danbooru
  - e621
  - dinov3
  - vit
pipeline_tag: image-classification
---

# DINOv3 ViT-H/16+ Booru Tagger

A multi-label image tagger trained on **e621** and **Danbooru** annotations, using a
[DINOv3 ViT-H/16+](https://huggingface.co/facebook/dinov3-vith16plus-pretrain-lvd1689m)
backbone fine-tuned end-to-end with a single linear projection head.

## Model Details

| Property | Value |
|---|---|
| Backbone | `facebook/dinov3-vith16plus-pretrain-lvd1689m` |
| Architecture | ViT-H/16+ · 32 layers · hidden dim 1280 · 20 heads · SwiGLU MLP · RoPE · 4 register tokens |
| Head | `Linear((1 + 4) × 1280 → 74 625)` — CLS + 4 register tokens concatenated |
| Vocabulary | **74 625 tags** (min frequency ≥ 50 across training set) |
| Input resolution | Any multiple of 16 px — trained at 512 px, generalises to higher resolutions |
| Input normalisation | ImageNet mean/std `[0.485, 0.456, 0.406]` / `[0.229, 0.224, 0.225]` |
| Output | Raw logits — apply `sigmoid` for per-tag probabilities |
| Parameters | ~632 M (backbone) + ~480 M (head) |

## Training

| Hyperparameter | Value |
|---|---|
| Training data | e621 + Danbooru (parquet) |
| Batch size | 32 |
| Learning rate | 1e-6 |
| Warmup steps | 50 |
| Loss | `BCEWithLogitsLoss` with per-tag `pos_weight = (neg/pos)^(1/T)`, cap 100 |
| Optimiser | AdamW (β₁=0.9, β₂=0.999, wd=0.01) |
| Precision | bfloat16 (backbone) / float32 (projection + loss) |
| Hardware | 2× GPU, ThreadPoolExecutor + NCCL all-reduce |

## Usage

### Standalone (no `transformers` dependency)

```python
from inference_tagger_standalone import Tagger

tagger = Tagger(
    checkpoint_path="tagger_proto.safetensors",
    vocab_path="tagger_vocab_with_categories.json",
    device="cuda",
)

tags = tagger.predict("photo.jpg", topk=40)
# → [("solo", 0.98), ("anthro", 0.95), ...]

# or threshold-based
tags = tagger.predict("https://example.com/image.jpg", threshold=0.35)
```

### CLI

```bash
# top-30 tags, pretty output
python inference_tagger_standalone.py \
    --checkpoint tagger_proto.safetensors \
    --vocab tagger_vocab_with_categories.json \
    --images photo.jpg https://example.com/image.jpg \
    --topk 30

# comma-separated string (pipe into diffusion trainer)
python inference_tagger_standalone.py ... --format tags

# JSON
python inference_tagger_standalone.py ... --format json
```

### Web UI

```bash
pip install fastapi uvicorn jinja2 aiofiles

python tagger_ui_server.py \
    --checkpoint tagger_proto.safetensors \
    --vocab tagger_vocab_with_categories.json \
    --port 7860
# → open http://localhost:7860
```

## Files

| File | Description |
|---|---|
| `*.safetensors` | Model weights (bfloat16) |
| `tagger_vocab_with_categories.json` | `{"idx2tag": [...]}` — 74 625 tag strings ordered by training frequency |
| `inference_tagger_standalone.py` | Self-contained inference script (no `transformers` dep) |
| `tagger_ui_server.py` | FastAPI + Jinja2 web UI server |

## Tag Vocabulary

Tags are sourced from e621 and Danbooru annotations and cover:

- **Subject** — species, character count, gender (`solo`, `duo`, `anthro`, `1girl`, `male`, …)
- **Body** — anatomy, fur/scale/skin markings, body parts
- **Action / pose** — `looking at viewer`, `sitting`, …
- **Scene** — background, lighting, setting
- **Style** — `digital art`, `hi res`, `sketch`, `watercolor`, …
- **Rating** — explicit content tags are included; filter as needed for your use case

Minimum tag frequency threshold: **50** occurrences across the combined dataset.

## Limitations

- Evaluated on booru-style illustrations and furry art; performance on photographic
  images or other art styles is untested.
- The vocabulary reflects the biases of e621 and Danbooru annotation practices.

## License

Apache 2.0