how to solve this problem?

[langongjin]

how to solve this problem as the follow photo?

[langongjin]

Is anybody help to solve this problem? Thank you very much!

[chutsu]

looks like your calibrations are off, else it would have projected the detected tags right on top.

[langongjin]

Thank you very much!
Do you know how to solve this problem, maybe a github source or example to do.....

[chutsu]

The best thing is to actually understand camera calibration, you can obtain your camera properties such as focal length fx, fy, principle points cx, cy, and distortion coefficients using OpenCV's own calibration functions (opencv docs). This website does a very good job of explaining what the camera parameters all mean (see this)

AprilTags needs 3 things:

• Focal length in x and y
• Principle point in x and y
• Tag size (side length in meters)

[langongjin]

Thank you very much!