import cv2
import numpy as np
from PIL import Image, ImageEnhance


# 方案一
def preprocess_image001(image):
    # 將影像轉換為 NumPy 數組
    image = np.array(image)
    # 轉為灰階影像
    gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
    # 調整對比度
    enhancer = ImageEnhance.Contrast(Image.fromarray(gray))
    enhanced_image = enhancer.enhance(2)
    # 二值化
    _, binary = cv2.threshold(np.array(enhanced_image), 0, 255, cv2.THRESH_BINARY + cv2.THRESH_OTSU)
    # 去雜訊
    denoised = cv2.fastNlMeansDenoising(binary, None, 30, 7, 21)
    return Image.fromarray(denoised)