OpenCV 形态学转换

综述

OpenCV中的形态学转换操作有七种：腐蚀，膨胀，开运算，闭运算，形态学梯度，礼帽，黑帽。

API参照表

中文名	英文名	api	原理	个人理解
腐蚀	erode	erosion = cv2.erode(src=girl_pic, kernel=kernel)	在窗中，只要含有０，则窗内全变为０，可以去浅色噪点	浅色成分被腐蚀
膨胀	dilate	dilation = cv2.dilate(src=girl_pic, kernel=kernel)	在窗中，只要含有１，则窗内全变为１，可以增加浅色成分	浅色成分得膨胀
开运算	morphology-open	opening = cv2.morphologyEx(girl_pic, cv2.MORPH_OPEN, kernel)	先腐蚀，后膨胀，去白噪点	先合再开，对浅色成分不利
闭运算	morphology-close	closing = cv2.morphologyEx(girl_pic, cv2.MORPH_CLOSE, kernel)	先膨胀，后腐蚀，去黑噪点	先开再合，浅色成分得势
形态学梯度	morphology-grandient	gradient = cv2.morphologyEx(girl_pic, cv2.MORPH_GRADIENT, kernel)	一幅图像腐蚀与膨胀的区别，可以得到轮廓	数值上解释为：膨胀减去腐蚀
礼帽	tophat	tophat = cv2.morphologyEx(girl_pic, cv2.MORPH_TOPHAT, kernel)	原图像减去开运算的差	数值上解释为：原图像减去开运算
黑帽	blackhat	blackhat = cv2.morphologyEx(girl_pic, cv2.MORPH_BLACKHAT, kernel)	闭运算减去原图像的差	数值上解释为：闭运算减去原图像

# -*- coding: utf-8 -*-

import cv2
import numpy as np

girl_pic = cv2.imread('timg.jpg')

kernel = np.ones((5, 5), np.uint8)

# erode 腐蚀
erosion = cv2.erode(src=girl_pic, kernel=kernel)
cv2.imshow('erosion', erosion)
cv2.imwrite('pic/erosion.jpg', erosion)

# dilate　膨胀
dilation = cv2.dilate(src=girl_pic, kernel=kernel)
cv2.imshow('dilation', dilation)
cv2.imwrite('pic/dilation.jpg', dilation)

# open　开运算
opening = cv2.morphologyEx(girl_pic, cv2.MORPH_OPEN, kernel)
cv2.imshow('opening', opening)
cv2.imwrite('pic/opening.jpg', opening)

# close　闭运算
closing = cv2.morphologyEx(girl_pic, cv2.MORPH_CLOSE, kernel)
cv2.imshow('closing', closing)
cv2.imwrite('pic/closing.jpg', closing)

# gradient　形态学梯度
gradient = cv2.morphologyEx(girl_pic, cv2.MORPH_GRADIENT, kernel)
cv2.imshow('gradient', gradient)
cv2.imwrite('pic/gradient.jpg', gradient)

# tophat　礼帽
tophat = cv2.morphologyEx(girl_pic, cv2.MORPH_TOPHAT, kernel)
cv2.imshow('tophat', tophat)
cv2.imwrite('pic/tophat.jpg', tophat)

# blackhat　黑帽
blackhat = cv2.morphologyEx(girl_pic, cv2.MORPH_BLACKHAT, kernel)
cv2.imshow('blackhat', blackhat)
cv2.imwrite('pic/blackhat.jpg', blackhat)

# cv2.add(open, tophat)　cv2.add(开运算, 礼帽)
open_and_tophat = cv2.add(opening, tophat)
cv2.imshow('open_and_tophat', open_and_tophat)
cv2.imwrite('pic/open_and_tophat.jpg', open_and_tophat)

# close-blackhat　闭运算-黑帽
close_subtract_blackhat = closing - blackhat
cv2.imshow('close_subtract_blackhat', close_subtract_blackhat)
cv2.imwrite('pic/close_subtract_blackhat.jpg', close_subtract_blackhat)
k = cv2.waitKey(0)

if k == 27:  # 按下ESC退出
    cv2.destroyAllWindows()

https://blog.youkuaiyun.com/jningwei/article/details/76101668