Opencv fisheye undistort without checker board approach

Question

I am looking if there is any way we can identify the camera calibration matrix and others to undistort a fisheye image without the checkerboard approach in OpenCV. This is because my current setup doesn't allow me to take some sample pictures out of it. So required an alternative approach. Preferably using OpenCV (Python). Thanks in advance.

Answer 1

Recently there are some AI approches using a single image. E.g. https://github.com/alexvbogdan/DeepCalib.

But I never tried and don't know if it works.