Predicting Ellipses on the edge of my image

Hi,

I have a problem regarding my matlab app which should detect ellipses.

It works for those that are fully visible, but the ones on the edge are not that easy...

The first problem is, that you can't predict the size of an ellipse if less than half its are is visible since it basically can take on any size.

If more than half of its area is visible, you should be able to predict its size (see the inserted image for better understanding).

Has anybody an idea how to solve that problem?

The best solution would be to predict the size of the ones with more than half the area visible and delete or ignore the ones with less than half the area visible...

Thanks in advance and best regards

Karsten