Ellipse detection in image

Hello everyone !

I’m trying to find the center of each spherical part to be able to draw an axis between this point and the middle of the spherical part.

For that I have already done the edge detection so now i try to find the ellipse that did the best with these shapes.

The red one is fixed but it can happen that the blue part is tilted. It is therefore the angle between the central axis of the two parts that I wish to measure. This is the measure that I would like to do automatically.

The center axis is of the red part is calculated as the midpoint between the 2 visible segment The center of the blue one is calculated as the midpoint of the intersection of the 2 circumferences that fit the top and bottom face

Any idea ?

Thank you

Thibault