app.py

import gradio as gr
from huggingface_hub import hf_hub_download
from ultralytics import YOLO
from PIL import Image, ImageDraw, ImageFont
import numpy as np

# Download and load model
model_path = hf_hub_download(repo_id="chuuhtetnaing/face-detection-yolo26n", filename="best.pt")
model = YOLO(model_path)


def crop_face_with_padding(image, bbox, padding_ratio=0.15):
    """Crop face with padding, handling edge cases."""
    img_w, img_h = image.size
    x1, y1, x2, y2 = bbox

    box_w = x2 - x1
    box_h = y2 - y1

    pad_w = int(box_w * padding_ratio)
    pad_h = int(box_h * padding_ratio)

    # Apply padding with boundary checks
    new_x1 = max(0, int(x1 - pad_w))
    new_y1 = max(0, int(y1 - pad_h))
    new_x2 = min(img_w, int(x2 + pad_w))
    new_y2 = min(img_h, int(y2 + pad_h))

    return image.crop((new_x1, new_y1, new_x2, new_y2))


def detect_faces(image):
    """Detect faces and return annotated image + cropped faces."""
    if image is None:
        return None, None

    image = Image.fromarray(image) if isinstance(image, np.ndarray) else image

    # Run detection
    results = model(image)[0]

    # Draw bounding boxes
    annotated = image.copy()
    draw = ImageDraw.Draw(annotated)

    cropped_faces = []

    for box in results.boxes:
        x1, y1, x2, y2 = box.xyxy[0].tolist()
        conf = box.conf[0].item()

        # Draw rectangle and label
        draw.rectangle([x1, y1, x2, y2], outline="green", width=20)
        font = ImageFont.load_default(size=200)
        draw.text((x1, y1 - 200), f"{conf:.2f}", fill="green", font=font)

        # Crop with padding
        cropped = crop_face_with_padding(image, (x1, y1, x2, y2))
        cropped_faces.append(cropped)

    # Create gallery of cropped faces
    cropped_gallery = cropped_faces if cropped_faces else None

    return annotated, cropped_gallery


with gr.Blocks(css=".main-row { margin-top: 30px !important; }") as demo:
    gr.Markdown("<h1 style='text-align: center; margin-top: 20px'>Face Detection with YOLO26n</h1>")

    with gr.Row(elem_classes="main-row"):
        with gr.Column(scale=1):
            input_image = gr.Image(label="Upload Image", type="pil", height=400)
            detect_btn = gr.Button("Detect Faces", variant="primary")

        with gr.Column(scale=1):
            with gr.Row():
                output_image = gr.Image(label="Detected Faces", height=400)
                cropped_gallery = gr.Gallery(label="Cropped Faces", columns=2, height=400)

    detect_btn.click(
        fn=detect_faces,
        inputs=input_image,
        outputs=[output_image, cropped_gallery]
    )

if __name__ == "__main__":
    demo.launch()