import numpy as np
import cv2
from PIL import Image

IMAGE_SIZE = 128

def preprocess_for_cnn(image: Image.Image):
    img = np.array(image.convert("L"))
    img = cv2.resize(img, (IMAGE_SIZE, IMAGE_SIZE))
    img = img.astype(np.float32) / 255.0
    img = np.expand_dims(img, axis=(0, -1))
    return img