关于opencv（）中的腐蚀操作，我操作过后会让原来的圆变形，怎么让圆腐蚀后不变形依旧保持圆形？

Question

代码：
import cv2 as cv
import numpy as np
pie=cv.imread('d:/pic/pie.png')
kernel=np.ones((7,7),np.uint8)
dilate=cv.dilate(pie,kernel,iterations=10)
erosion=cv.erode(pie,kernel,iterations=10)
res=np.hstack((pie,dilate,erosion))
cv.imshow('res',res)
cv.waitKey(0)
cv.destroyAllWindows()

结果：

Answer 1

这个原因是对于圆形的物体使用正方形的核去做膨胀和腐蚀就会变的像四边形，只要修改kernel变成圆形就好了；

import cv2 as cv
    import numpy as np
    import math

    pie = cv.imread('0000.png')
    kernel = np.ones((7, 7), np.uint8)
    kernel_re = []
    rows, cols = kernel.shape
    for i in range(rows):
        result = [0 if math.sqrt((i-3)**2+(j-3)**2) > 3 else 1 for j in range(cols)]
        kernel_re.append(result)
    kernel_re = np.array(kernel_re, np.uint8)
    print(kernel_re, kernel)
    print(type(kernel_re), type(kernel))
    print(kernel_re.shape, kernel.shape)
    dilate = cv.dilate(pie, kernel, iterations=10)
    erosion = cv.erode(pie, kernel_re, iterations=10)
    res = np.hstack((pie, dilate, erosion))
    cv.imshow('res', res)
    cv.waitKey(0)
    cv.destroyAllWindows()