import cv2
img = cv2.imread('C:\\a\\laoshitimu.jpg')
b = cv2.cvtColor(img,cv2.COLOR_BGR2GRAY)
ret, binary = cv2.threshold(b,127,255,cv2.THRESH_BINARY)
q,w = cv2.findContours(b, cv2.RETR_TREE, cv2.CHAIN_APPROX_SIMPLE)
beifen=img.copy()
q1=cv2.drawContours(beifen,q,3,(0,255,0),2)
for cnt in range(4):
ar = cv2.arcLength(q[cnt],True)
ep=0.01*ar
ap=cv2.approxPolyDP(q,ep,True)
len(ap)
但运行后,会报这样的错:
这是为什么?