Hello, i'm trying to search for an area of an image.

Hello, i'm trying to search for an area of a geometry which has the shape of approx. circle (as attached). I've tried using the imfill function but it doesn't work possibly because there are gaps due to the two electrodes. imclose also produce unsatisfactory results. How can I cut through the gap to form connected circle? Thanks in advance

Answer 1

[Alessandro Masullo]

I don't know if this solution works for you, but I would use histeq to equalize the image first, then conv2 to convolve the image with a Gaussian (or imfilter), and finally edge with "canny" to detect the shape of the object. You'll have to play with the Gaussian and the canny thresholds, but you could get good results.

[Suardi Suhaimi]

Thanks Allesandro for the reply.

I could see some decent results indeed. However, I still need to discard everything inside the circle (esp. the protruding features which are actually a pair of electrodes), only then can i find the area of the circle.

Thanks again.

Answer 2

[Walter Roberson]

imdilate and then imerode to get it to join the halves. Or if you have R2014b or later, you could get the coordinates of the boundary points and then use boundary() on them to find a hull that contains them.

[Suardi Suhaimi]

Thanks Walter, As the matter of fact I do have 2014b. I will try it out & repost the results.