openn Cv2 drawing Contours
-1
i m running this code but i m getting an error
cv2.drawContours(image,contours,-1,(0,255,0),3)
error: OpenCV(3.4.3) D:BuildOpenCVopencv-3.4.3modulesimgprocsrcdrawing.cpp:2511: error: (-215:Assertion failed) npoints > 0 in function 'cv::drawContours'
import cv2
import numpy as np
image=cv2.imread("C:/Users/AnushkaGupta/Desktop/image database/input1.jpg")
cv2.imshow("original image",image)
cv2.waitKey(0)
gray=cv2.cvtColor(image,cv2.COLOR_BGR2GRAY)
edged=cv2.Canny(gray,30,200)
cv2.imshow("Canny Edges",edged)
cv2.waitKey(0)
contours,hierarchy, _=cv2.findContours(edged,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_NONE)
cv2.imshow("canny Edges After Contouring",edged)
cv2.waitKey(0)
print("Number of Contours found ="+str(len(contours)))
cv2.drawContours(image,contours,-1,(0,255,0),3)
cv2.imshow("Contours",image)
cv2.waitKey(0)
cv2.destroyAllWindows()
python opencv
edited Nov 21 '18 at 17:33
eyllanesc
84k103562
asked Nov 21 '18 at 17:30
Abhinav GuptaAbhinav Gupta
1
add a comment |
-1
i m running this code but i m getting an error
cv2.drawContours(image,contours,-1,(0,255,0),3)
error: OpenCV(3.4.3) D:BuildOpenCVopencv-3.4.3modulesimgprocsrcdrawing.cpp:2511: error: (-215:Assertion failed) npoints > 0 in function 'cv::drawContours'
import cv2
import numpy as np
image=cv2.imread("C:/Users/AnushkaGupta/Desktop/image database/input1.jpg")
cv2.imshow("original image",image)
cv2.waitKey(0)
gray=cv2.cvtColor(image,cv2.COLOR_BGR2GRAY)
edged=cv2.Canny(gray,30,200)
cv2.imshow("Canny Edges",edged)
cv2.waitKey(0)
contours,hierarchy, _=cv2.findContours(edged,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_NONE)
cv2.imshow("canny Edges After Contouring",edged)
cv2.waitKey(0)
print("Number of Contours found ="+str(len(contours)))
cv2.drawContours(image,contours,-1,(0,255,0),3)
cv2.imshow("Contours",image)
cv2.waitKey(0)
cv2.destroyAllWindows()
python opencv
edited Nov 21 '18 at 17:33
eyllanesc
84k103562
asked Nov 21 '18 at 17:30
Abhinav GuptaAbhinav Gupta
1
add a comment |
-1
-1
-1
i m running this code but i m getting an error
cv2.drawContours(image,contours,-1,(0,255,0),3)
error: OpenCV(3.4.3) D:BuildOpenCVopencv-3.4.3modulesimgprocsrcdrawing.cpp:2511: error: (-215:Assertion failed) npoints > 0 in function 'cv::drawContours'
import cv2
import numpy as np
image=cv2.imread("C:/Users/AnushkaGupta/Desktop/image database/input1.jpg")
cv2.imshow("original image",image)
cv2.waitKey(0)
gray=cv2.cvtColor(image,cv2.COLOR_BGR2GRAY)
edged=cv2.Canny(gray,30,200)
cv2.imshow("Canny Edges",edged)
cv2.waitKey(0)
contours,hierarchy, _=cv2.findContours(edged,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_NONE)
cv2.imshow("canny Edges After Contouring",edged)
cv2.waitKey(0)
print("Number of Contours found ="+str(len(contours)))
cv2.drawContours(image,contours,-1,(0,255,0),3)
cv2.imshow("Contours",image)
cv2.waitKey(0)
cv2.destroyAllWindows()
python opencv
edited Nov 21 '18 at 17:33
eyllanesc
84k103562
asked Nov 21 '18 at 17:30
Abhinav GuptaAbhinav Gupta
1
i m running this code but i m getting an error
cv2.drawContours(image,contours,-1,(0,255,0),3)
error: OpenCV(3.4.3) D:BuildOpenCVopencv-3.4.3modulesimgprocsrcdrawing.cpp:2511: error: (-215:Assertion failed) npoints > 0 in function 'cv::drawContours'
import cv2
import numpy as np
image=cv2.imread("C:/Users/AnushkaGupta/Desktop/image database/input1.jpg")
cv2.imshow("original image",image)
cv2.waitKey(0)
gray=cv2.cvtColor(image,cv2.COLOR_BGR2GRAY)
edged=cv2.Canny(gray,30,200)
cv2.imshow("Canny Edges",edged)
cv2.waitKey(0)
contours,hierarchy, _=cv2.findContours(edged,cv2.RETR_EXTERNAL,cv2.CHAIN_APPROX_NONE)
cv2.imshow("canny Edges After Contouring",edged)
cv2.waitKey(0)
print("Number of Contours found ="+str(len(contours)))
cv2.drawContours(image,contours,-1,(0,255,0),3)
cv2.imshow("Contours",image)
cv2.waitKey(0)
cv2.destroyAllWindows()
python opencv
python opencv
edited Nov 21 '18 at 17:33
eyllanesc
84k103562
asked Nov 21 '18 at 17:30
Abhinav GuptaAbhinav Gupta
1
edited Nov 21 '18 at 17:33
eyllanesc
84k103562
asked Nov 21 '18 at 17:30
Abhinav GuptaAbhinav Gupta
1
edited Nov 21 '18 at 17:33
eyllanesc
84k103562
edited Nov 21 '18 at 17:33
eyllanesc
84k103562
edited Nov 21 '18 at 17:33
eyllanesc
84k103562
84k103562
asked Nov 21 '18 at 17:30
Abhinav GuptaAbhinav Gupta
1
asked Nov 21 '18 at 17:30
Abhinav GuptaAbhinav Gupta
1
asked Nov 21 '18 at 17:30
Abhinav GuptaAbhinav Gupta
1
1
add a comment |
add a comment |
1 Answer
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When you collect the output of findContours(), the order should be as follows:
image, contours, hierarchy = cv2.findContours(...)
In your specific case you should write (I omitted the imshow steps):
import cv2
import numpy as np
image = cv2.imread("./input1.jpg")
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
edged = cv2.Canny(gray, 30, 200)
_, contours, hierarchy = cv2.findContours(edged, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_NONE)
print(f"Number of Contours found = {len(contours)}")
cv2.drawContours(image, contours, -1, (0,255,0), 3)
answered Nov 21 '18 at 18:03
leoburgyleoburgy
1107
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
0
When you collect the output of findContours(), the order should be as follows:
image, contours, hierarchy = cv2.findContours(...)
In your specific case you should write (I omitted the imshow steps):
import cv2
import numpy as np
image = cv2.imread("./input1.jpg")
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
edged = cv2.Canny(gray, 30, 200)
_, contours, hierarchy = cv2.findContours(edged, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_NONE)
print(f"Number of Contours found = {len(contours)}")
cv2.drawContours(image, contours, -1, (0,255,0), 3)
answered Nov 21 '18 at 18:03
leoburgyleoburgy
1107
add a comment |
0
When you collect the output of findContours(), the order should be as follows:
image, contours, hierarchy = cv2.findContours(...)
In your specific case you should write (I omitted the imshow steps):
import cv2
import numpy as np
image = cv2.imread("./input1.jpg")
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
edged = cv2.Canny(gray, 30, 200)
_, contours, hierarchy = cv2.findContours(edged, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_NONE)
print(f"Number of Contours found = {len(contours)}")
cv2.drawContours(image, contours, -1, (0,255,0), 3)
answered Nov 21 '18 at 18:03
leoburgyleoburgy
1107
add a comment |
0
0
0
When you collect the output of findContours(), the order should be as follows:
image, contours, hierarchy = cv2.findContours(...)
In your specific case you should write (I omitted the imshow steps):
import cv2
import numpy as np
image = cv2.imread("./input1.jpg")
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
edged = cv2.Canny(gray, 30, 200)
_, contours, hierarchy = cv2.findContours(edged, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_NONE)
print(f"Number of Contours found = {len(contours)}")
cv2.drawContours(image, contours, -1, (0,255,0), 3)
answered Nov 21 '18 at 18:03
leoburgyleoburgy
1107
When you collect the output of findContours(), the order should be as follows:
image, contours, hierarchy = cv2.findContours(...)
In your specific case you should write (I omitted the imshow steps):
import cv2
import numpy as np
image = cv2.imread("./input1.jpg")
gray = cv2.cvtColor(image, cv2.COLOR_BGR2GRAY)
edged = cv2.Canny(gray, 30, 200)
_, contours, hierarchy = cv2.findContours(edged, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_NONE)
print(f"Number of Contours found = {len(contours)}")
cv2.drawContours(image, contours, -1, (0,255,0), 3)
answered Nov 21 '18 at 18:03
leoburgyleoburgy
1107
edited Nov 21 '18 at 18:09
answered Nov 21 '18 at 18:03
leoburgyleoburgy
1107
answered Nov 21 '18 at 18:03
leoburgyleoburgy
1107
answered Nov 21 '18 at 18:03
leoburgyleoburgy
1107
1107
add a comment |
add a comment |
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