彩色label图转换黑白label图「代码」

import cv2
import matplotlib.pyplot as plt
import matplotlib
import numpy as np
matplotlib.rcParams['font.sans-serif'] = ['SimHei']     
matplotlib.rcParams['axes.unicode_minus'] = False


# 读取灰度图像
img = cv2.imread("/Users/yym/Desktop/data_json/label/21label.png", 0)
print("原图的shape: ", img.shape)
plt.subplot(2, 2, 1)
plt.imshow(img, cmap='gray')
plt.title("img")

# 1.OTSU二值化
ret2, mask_OTSU = cv2.threshold(img, 0, 255, cv2.THRESH_BINARY + cv2.THRESH_OTSU)
print("OTSU的shape: ", mask_OTSU.shape)
plt.subplot(2, 2, 4)
plt.imshow(mask_OTSU, cmap='gray')
plt.title("OTSU")
cv2.imwrite('/Users/yym/Desktop/data_json/label/21_label.png',mask_OTSU)#图像保存地址

原图label：

处理后的label图：