计算边缘处圆心之间的距离

Question

How can i Calculate Distance between center of the circle and extreme edges.

Below is the sample image and the green line is the Distance which i want to calculate.

How can do this using Open CV?

Answer 1

Hints:

Not easy to make this reliably. In the first place, make sure that you take the picture in front, to avoid parallax errors.

Possibly find the central circle(s) by Hough. This gives you the center.

Now the hard par is to segment the blades. Possibly by thresholding on a luminance image or anything close to that cream color. Or using a general segmentation method.

Then figure out which blade is segmented most accurately, and find the longest distance from the center to any point of the blade (that gives you the tip).

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If you don't care about accuracy, it is not impossible that Hough gives you the outer circle.