Closing a contour curve in OpenCV

Question

I\'m using OpenCV (Canny + findCountours) to find external contours of objects. The curve drawn is typically almost, but not entirely, closed. I\'d like to close it - to f

Answer 1

A little late, but I just had to deal with this myself. If you perform an opening operation (erosion followed by dilation) prior to the Canny edge detection, the edges you detect should be more continuous, resulting in better contours. This method appears to be fairly robust. I mentioned this in another post and posted a code sample as part of a recent question.

Answer 2

Using PolyLine method to draw contours

cv2.PolyLine(img, points, is_closed=True, 255, thickness=1, lineType=8, shift=0)

Read the docs for further details: http://docs.opencv.org/2.4/modules/core/doc/drawing_functions.html

Mark answered if it resolved your problem. If not then let me know.