# FaceNet Triplet ResNet Model (Grayscale, 112x112, Mobile-friendly)

This repository provides a FaceNet-style triplet embedding model using ResNet backbones, optimized for mobile and edge devices:
- Input: **Grayscale images** (`3` channel)
- Resolution: **112x112 pixels**
- Output: **Embeddings** suitable for face recognition and verification

## Model Details

- **Architecture:** ResNet50 with NdLinear
- **Embedding Dimension:** 512
- **Input:** 3x112x112 grayscale images (NCHW format)
- **Exported weights:** `model.safetensors`
- **Config:** `config.json`

## Usage

### 1. Clone or Download Files

Download/copy the `models/` directory and dependencies (`ndlinear.py`, etc.) to your project.

### 2. Install requirements

```bash
pip install torch safetensors
```

### 3. Load the model

```python
from models.resnet import Resnet50Triplet  # or your chosen variant

model = Resnet50Triplet.from_pretrained(".", safe_serialization=True)
model.eval()
```

### 4. Use for Face Recognition

Obtain a face embedding from an input image, and compare embeddings (e.g., with cosine similarity) to recognize or verify identities.

```python
import torch

# Example: batch of 1 grayscale image of 112x112
images = torch.randn(1, 1, 112, 112)  # (batch_size, channels, height, width)

with torch.no_grad():
    embedding = model(images)  # embedding output suitable for face recognition
print(embedding.shape)  # (batch_size, embedding_dim)
```

To perform recognition or verification, compare the embedding against a database of known face embeddings using distance/similarity metrics.

## Files

- `model.safetensors` - Model weights
- `config.json` - Loader configuration
- `models/` - Model definition files
- `README.md` - This file

## Notes

- Model is optimized for runtime on edge/mobile devices (reduced input size, grayscale input for lower computational load)
- Make sure your image preprocess pipeline produces three identical grayscaled channels, 112x112 images.

## Credits

- Backbone based on [PyTorch torchvision ResNet](https://pytorch.org/vision/stable/models/generated/torchvision.models.resnet50.html)
- Architecture inspired by [Facenet PyTorch](https://github.com/timesler/facenet-pytorch)

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*For contributions or issues, open a discussion or pull request.*