How to use OpenCV imopen in Matlab?

I see that the documentation for it is at: http://kyamagu.github.io/mexopencv/matlab/morphologyEx.html

However, it's not working for me. If I try any of the following:

 im_open = cv.morphologyEx(im, open, [5 5]);
    im_open = cv.morphologyEx(im, "open", [5 5]);
    im_open = cv.morphologyEx(im, cv.Open, [5 5]);
    im_open = cv.morphologyEx(im, cv.MORPH_OPEN, [5 5]);
    im_open = cv.morphologyEx(im, MORPH_OPEN, [5 5]);

Then I get errors like `wrong number of arguments` or `undefined variable 'cv' or class 'cv.open'`

If I try

dst = open(im, [5 5]);

Then I get

wrong number of arguments

If I try

elem = cv.getStructuringElement(cv2.MORPH_RECT, (5,5))

then I get

error: invalid expression. When calling a function or indexing a variable, use parenthesis. Otherwise, check for mismatched delimiters

I just want to perform the equivalent of

im_open = imopen(im, strel('disk', 5));

But using OpenCV within Matlab. How can I do this?

Answer 1

[Constantino Carlos Reyes-Aldasoro]

Why don't you use matlab's native imopen function?

https://uk.mathworks.com/help/images/ref/imopen.html