python - 查找图像中的圆心

Question

我对编程相当陌生，需要编写一个程序来找到位于正方形图像每个角落的 4 个圆盘（圆）的中心。

我不知道光盘的确切坐标，但对它们有一个很好的近似值。我怎样才能找到 4 个圆盘中每个圆盘的中心位置？

标签： pythonimagedetection

Answer 1

moments您可以使用OpenCV查找形状的质心：

import cv2

# read image through command line
img = cv2.imread(args["ipimage"])
# or load it from a path
#img = cv2.imread(R"/usr/home/dinges/4c.png")

# convert the image to grayscale
gray_image = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
# convert the grayscale image to binary image
ret,thresh = cv2.threshold(gray_image,127,255,0)

# find contours in the binary image
im2, contours, hierarchy = cv2.findContours(thresh,cv2.RETR_TREE,cv2.CHAIN_APPROX_SIMPLE)
for c in contours:
   # calculate moments for each contour
   M = cv2.moments(c)

   # calculate x,y coordinate of center
   cX = int(M["m10"] / M["m00"])
   cY = int(M["m01"] / M["m00"])
   print('centroid: X:{}, Y:{}'.format(cX, cY)) 
   cv2.circle(img, (cX, cY), 5, (255, 255, 255), -1)
   cv2.putText(img, "centroid", (cX -25, cY -25),cv2.FONT_HERSHEY_SIMPLEX, 0.5, (255, 255, 255), 2)

   # display the image
   cv2.imshow("Image", img)
   cv2.waitKey(0)

参考：使用 OpenCV 查找 Blob（质心）的中心