Python OpenCV4趣味应用系列(七)---画龙点睛轮廓点绘制

import numpy as np

import cv2

font = cv2.FONT_HERSHEY_SIMPLEX

img = cv2.imread('1.jpg')

cv2.imshow('src',img)

temp = img.copy()

black_img = np.zeros(img.shape,np.uint8)

gray = cv2.cvtColor(temp,cv2.COLOR_BGR2GRAY)

ret,thresh = cv2.threshold(gray, 150, 255, cv2.THRESH_BINARY_INV)

cv2.imshow("thres", thresh)

#contours,hierarchy = cv2.findContours(thresh, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_NONE)

contours,hierarchy = cv2.findContours(thresh, cv2.RETR_LIST, cv2.CHAIN_APPROX_NONE)

flag = 0
for i in range(0,len(contours)):#遍历所有轮廓
  for j in range(0,len(contours[i])):#遍历第i个轮廓的所有点
    cv2.drawContours(black_img,contours[i],j,(0,255,255),2)
    cv2.imshow("img",black_img)
    if cv2.waitKey(1)&0xFF ==27: #按下Esc键退出
      flag = 1
      break
  if flag:
    break