Transformation of 3D objects related to vanishing points and horizon line

This is nowhere near my cup of tea so handle with extreme prejudice and also far form solution just some start point hints… First of all we need to define some constraints/assumptions in order to make this to work. user selects 4 lines representing 2 perpendicular planes and these 2 QUADs have the same height … Read more

Get 3D coordinates from 2D image pixel if extrinsic and intrinsic parameters are known

If you got extrinsic parameters then you got everything. That means that you can have Homography from the extrinsics (also called CameraPose). Pose is a 3×4 matrix, homography is a 3×3 matrix, H defined as H = K*[r1, r2, t], //eqn 8.1, Hartley and Zisserman with K being the camera intrinsic matrix, r1 and r2 … Read more

Computing x,y coordinate (3D) from image point

Given your configuration, errors of 20-40mm at the edges are average. It looks like you’ve done everything well. Without modifying camera/system configuration, doing better will be hard. You can try to redo camera calibration and hope for better results, but this will not improve them alot (and you may eventually get worse results, so don’t … Read more

How to verify the correctness of calibration of a webcam?

Hmm, are you looking for “handsome” or “accurate”? Camera calibration is one of the very few subjects in computer vision where accuracy can be directly quantified in physical terms, and verified by a physical experiment. And the usual lesson is that (a) your numbers are just as good as the effort (and money) you put … Read more

tech