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when running this code `import numpy as np import cv2

image=cv2.imread('screenshoot10.jpg') cv2.imshow('input image', image)

gray=cv2.cvtColor(image,cv2.COLOR_BGR2GRAY)

edged=cv2.Canny(gray,30,200) cv2.imshow('canny edges',edged)

_, contours = cv2.findContours(edged,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_NONE) cv2.imshow('canny edges after contouring', edged)

print(contours) print('Numbers of contours found=' + str(len(contours)))

cv2.drawContours(image,contours,-1,(0,255,0),3) cv2.imshow('contours',image) cv2.waitKey(0) cv2.destroyAllWindows()`

getting an error

OpenCV(4.1.1) C:\projects\opencv-python\opencv\modules\imgproc\src\drawing.cpp:2509: error: (-215:Assertion failed) npoints > 0 in function 'cv::drawContours'

what am I doing wrong?

when running this code `import code

import numpy as np
import cv2
cv2
  
image=cv2.imread('screenshoot10.jpg')
cv2.imshow('input image', image)image)
 gray=cv2.cvtColor(image,cv2.COLOR_BGR2GRAY)
 
gray=cv2.cvtColor(image,cv2.COLOR_BGR2GRAY)
 
edged=cv2.Canny(gray,30,200)
cv2.imshow('canny edges',edged)edges',edged)
  
_, contours = cv2.findContours(edged,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_NONE)
cv2.imshow('canny edges after contouring', edged)edged)
  
print(contours)
print('Numbers of contours found=' + str(len(contours)))str(len(contours)))
  
cv2.drawContours(image,contours,-1,(0,255,0),3)
cv2.imshow('contours',image)
cv2.waitKey(0)
cv2.destroyAllWindows()`cv2.destroyAllWindows()

getting an error

OpenCV(4.1.1) C:\projects\opencv-python\opencv\modules\imgproc\src\drawing.cpp:2509: error: (-215:Assertion failed) npoints > 0 in function 'cv::drawContours'
'cv::drawContours'