If an image contains a large circle, but the top or bottom extends slightly outside of the image (circle is clipped), is there still any way to use Hough to detect the circle? In my tests, even though 90% of the circle is inside the image, the Hough function seems to get thrown off by the slightly clipped top or bottom. The result is that the circle is slightly smaller than ideal, and skewed (usually toward the right).
If Hough will not handle this, is there another appropriate function?