等效直径

import cv2
import numpy as np
o=cv2.imread('C:/Users/xpp/Desktop/coins.png')#原始图像
cv2.imshow("original",o)
gray=cv2.cvtColor(o,cv2.COLOR_BGR2GRAY)#将彩色图片转换为灰度图片
ret,binary=cv2.threshold(gray,127,255,cv2.THRESH_BINARY)#将灰度图片转换为二值图片
contours,hierarchy=cv2.findContours(binary,cv2.RETR_LIST,cv2.CHAIN_APPROX_SIMPLE)#计算图像轮廓
n=len(contours)
contoursImg=[]
for i in range(n):
    temp=np.zeros(o.shape,np.uint8)
    contoursImg.append(temp)
cv2.drawContours(o,contours[i],-1,(0,0,255),3)#绘制图像轮廓
cntArea=cv2.contourArea(contours[i])#计算轮廓面积
equiDiameter=np.sqrt(4*cntArea/np.pi)#计算等效直径大小的圆
print(equiDiameter)
cv2.circle(o,(100,100),int(equiDiameter/2),(0,0,255),3) #绘制等效直径大小的圆
cv2.imshow("result",o)
cv2.waitKey()
cv2.destroyAllWindows()