# Camera Calibration

Hello Forum

I am trying to determine the camera matrix so that I can extract the position of the camera in world coordinates. I have an image (below) and have all the points in world (meters) and pixel coordinates.

The problem is, all the points have the same height ie. Z = 0 and hence the matrix is singular.

Is there another way for me to obtain the camera matrix ?

Regards, Haziq

EDIT: In short, I would like to determine the location of the camera in world coordinates and this website http://ksimek.github.io/2012/08/14/de... extracts the camera location from the camera matrix. Is there any other way for me to get the location of the camera ??

Yes your matrix is singular because all Z are equal to 0. But It means you don't need Z (except in Quidditch). Delete column with z and ou will have a matrix which you can use to locate player. Except you will have a good localisation with foot player not the head player.

Hi, thanks for the reply. So the camera matrix would be a 3x3 matrix ? How would i extract the (XYZ) position of the camera ? I am trying to follow the steps here http://ksimek.github.io/2012/08/14/de... and I need a 3 x 4 camera matrix

You would extract X and Y coordinates only. I think it's not possible without some Z coordinates. You can use goal may be

Hi, is it possible for me to extract the 3x4 camera matrix if I only have 1 point with height ? I will use the goalpost like u say but that will only give me 1 height. The others will still be 0. Will it work ?

Yes it should work but you can two points in goal (left and right)