Automatically fit a circle on an arc in image and to plot the circle in the image.

I have an processed image (top image as shown here) where I have an arc portion that can be fitted into a circle. I need to fit an appropriate circle on this arc and plot it in the existing image (as shown in the bottom image). I need to fit the circle on the arc automatically as I have to go through batch of images for this process. How can I get the bottom image from the top one? FYI, the second image is cropped from word file and looks magnified.

Answer 1

[Jonas]

This may help you

[Anjan Goswami]

Dear Jonas, Could you please tell me how can I get the x and y coordinates of my arc from the image so that I can pass x and y through the circfit function?

[Jonas]

use

[y,x]=find(im);

on your image im. this finds all non zero elements in the image. you can then delete some points with big and small x coordinate to remove the influence of the non arc part at the ends of the white shape

[Anjan Goswami]

Thanks Jonas, it works.

Answer 2

[Stephan]

This example from the documentation appears to be suitable for your case.

[Anjan Goswami]

Thanks for your answer.