opencv 3, blobdetection, The function/feature is not implemented () in detectAndCompute

Question

I have a problem with opencv 3: I want to use a feature detector, SimpleBlobDetector, about to use filters by convexity and circularity. But when I try to execute the code, the

Answer 1

This is because you're using OpenCV 3.X, where (as of this writing) all of the examples you'll find online use OpenCV 2.X.

If you dig around, though, you'll find the transition guide: http://docs.opencv.org/master/db/dfa/tutorial_transition_guide.html#tutorial_transition_hints_headers

Which says you need to use:

Ptr algo = makePtr(...);
Ptr algo = SomeAlgo::create(...);

Instead of:

SomeAlgo algo(); // bad

So in this case, you'll need to use:

Ptr d = SimpleBlobDetector::create();

Or:

Ptr d = SimpleBlobDetector::create(params);

If you've got params.