# coding=utf-8
import cv2
import numpy as np
filename = 'woman.JPEG'
#读入图像,以灰度格式
img = cv2.imread(filename)
gray = cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)
canny1 = cv2.Canny(img,200,300)
#200:最小阈值 300:最大阈值
#灰度梯度高于maxVal被认为是边界
#低于minVal抛弃
cv2.imshow("canny",canny1)
cv2.waitKey()
cv2.destroyAllWindows()