It supports pinhole and fisheye camera models and undistortion is also performed. Of course, both of chess-board-detection and circle-pattern-detection are available. datasets folder includes 2 image-sequences. (Fisheye-calibration is implemented, but I didn't check this is correct.)
A checker-board is from https://www.mrpt.org/downloads/camera-calibration-checker-board_9x7.pdf .
This shows how to use cv::Stitcher. This is almost same as here.(https://docs.opencv.org/master/d8/d19/tutorial_stitcher.html)
This code generates 3d-points and camera poses by 2-viewes-geometry. You can learn how to use FindEssentialMat(), recoverPose(), triangulatePoints() and so on. In addtion, I made a viewer using OpenCV-Viz-Module. You can check it too.
This shows your opencv version.
It uses findHomography(), and seamlessCone() for blening. You can try with images in test_images folder.
Nothing to write.