如何计算轮廓opencv中的非零像素

import cv2
import numpy as np

image = cv2.imread('your_image.jpg', cv2.IMREAD_GRAYSCALE)  # 用灰度模式读取图像
_, binary_image = cv2.threshold(image, 127, 255, cv2.THRESH_BINARY)  # 二值化

contours, _ = cv2.findContours(binary_image, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)  # 找到轮廓

non_zero_pixels = cv2.countNonZero(binary_image)
print(f"非零像素数量 (方法一): {non_zero_pixels}")

non_zero_pixels = np.count_nonzero(binary_image)
print(f"非零像素数量 (方法二): {non_zero_pixels}")

# 在二值图像上绘制轮廓
contour_image = np.zeros_like(binary_image)
cv2.drawContours(contour_image, contours, -1, color=255, thickness=cv2.FILLED)

# 计算轮廓内非零像素数量
non_zero_pixels_in_contour = cv2.countNonZero(contour_image)
print(f"轮廓内的非零像素数量: {non_zero_pixels_in_contour}")