app/core/preprocessing.py

import numpy as np
import io
from PIL import Image

def preprocess_image(image_bytes: bytes, target_size=(224, 224)) -> np.ndarray:
    image = Image.open(io.BytesIO(image_bytes)).convert("RGB")
    image = image.resize(target_size)
    img_array = np.array(image, dtype=np.float32) / 255.0
    return np.expand_dims(img_array, axis=0)