Circle- Detection with Visual Basic

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To find circles in an image, you can use the Hough transform for circle, where the output is (x,y,radius) for each circle. Since you have the center, you could find the color of that point if it's what you want.

not with basic, sorry. you'll have to learn c++. .. or python .. or java .. or matlab ..

I think you should try use opencvsharp or emgu which pinvoke opencv.