Thresold a color with openCV

Question

I need some help. I want to thresold an image with the red colour. I get this image: !(http://www.hostingpics.net/viewer.php?id=652943Slection110.png)

I want to have a great triangle without discontinuity in order to detect corner. (Because like that all the discontinuity is consider like a corner)

I have tried dilate and all theses stuff but without success...

Do you have an idea about how i can improve this result ?

Thank you

Answer 1

Morphological operations seem the way to go.

I would start with a big dilation to connect the parts. Then, find the skeleton or thin the binary image with erosion.