# fast way to draw ellipse axes?

Is there any way to draw ellipse axes in opencv?

fast way to draw ellipse axes?

Is there any way to draw ellipse axes in opencv?

1

These are a couple of opencv functions regarding ellipses:

```
// this outputs to 'pts' the points representing an ellipse arc defined by the other parameters
Core.ellipse2Poly(center, axes, angle, arcStart, arcEnd, delta, pts);
// this draws an ellipse
Core.ellipse(img, center, axes, angle, startAngle, endAngle, color);
```

**axes** parameter is of type Size and means the width and height of the axes.

I will improve the answer if you provide more details.

If you have the RotatedRect that represents the ellipse then the middle of the RotatedRect four sides are the end of axes coordinates, right? So all you need is a method to get the coordinates of a point in the "middle" of a rectangle side. Let us know if you have troubles calculating that middle point.

Asked: **
2012-08-31 01:46:15 -0500
**

Seen: **1,016 times**

Last updated: **Aug 31 '12**

Copyright OpenCV foundation, 2012-2018. Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.

What information you have about the ellipse, do you know its center coordinates, width and height, more?