Camera Calibrator App Asymmetric Circles Grid Detection Issue

Hello,

I'm trying to calibrate a thermal camera by using the Camera Calibrator app with asymmetric circles grid pattern. After I loaded the input images and run the application, the message "No calibration patters were detected in the images" pops up.

An input image used as sample is reported below.

Now strange thing (for me): if I use on these images the function "detectCircleGridPoints", function that should be used in the Camera Calibrator App, it is absolutely capable to detect the circle centers in every image. One result shown below.

What I'm not considering? Any idea about a workaround to find camera parameter with these points highlighted?

Thanks.

Answer 1

[Giridharan Kumaravelu]

The Camera Calibrator App does not support Circle Grid Patterns with white circles. It assumes the images contain black circles and that is the reason you are not getting any detections in the app.

If you are using MATLAB R2022a or later versions, you can use the attached custom pattern detector for your application to detect the white circles. To learn more about how to use Custom Pattern Detectors in the Camera Calibrator App, see Custom Pattern Detectors.

If you are using older versions of MATLAB, you can calibrate your camera from the MATLAB commandline using estimateCameraParameters function.

[VaL V6]

It works perfectly! Thank you so much for the help.

[Brett Shoelson]

Seems like an easy enhancement: allow the passing of 'objectPolarity' as an input.