以下是一些建议:
import cv2
import numpy as np
frame = cv2.imread('image.jpg')
h, w = frame.shape[:2]
mask_color = (0, 50, 255) # isolate a repeating constant
# avoid setting a variable that is used only once, only if you REALLY need it to improve readability
# that's why `upper_value` and `lower_value` were removed.
# BTW, `lower_value` was unused in your code.
upper_mask = cv2.rectangle(frame, (0, 0), (w, int(0.5 * h)), mask_color, -1)
lower_mask = cv2.rectangle(frame, (0, h), (w, int(0.7 * h)), mask_color, -1)