Python OpenCV4趣味应用系列(九)---划痕缺陷检测实例

import cv2
import numpy as np
print (cv2.__version__)
minThres = 6

# 读取图像1
img1=cv2.imread('A.png')  
img2=cv2.imread('A.png')

# 中值滤波
img1 = cv2.medianBlur(img1,15)
# 图像差分
diff = cv2.absdiff(img1, img2)
cv2.imshow('diff',diff) #结果图

gray = cv2.cvtColor(diff, cv2.COLOR_BGR2GRAY)
# 二值化
_,thres = cv2.threshold(gray,minThres,255,cv2.THRESH_BINARY)
cv2.imshow('thres',thres)

# 查找轮廓
contours,hierarchy = cv2.findContours(thres, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_NONE)
#输出轮廓个数
print (len(contours))
 
for i in range(0,len(contours)):
  length = cv2.arcLength(contours[i],True)
  # 通过轮廓长度筛选
  if length > 35:
    cv2.drawContours(img2,contours[i],-1,(0,0,255),2)

cv2.imshow('result',img2) #结果图
cv2.waitKey(0)  
cv2.destroyAllWindows()