Undistort on X&Y co-ods not video?

Hi all.

I’m doing some tracking based work with a major fish-eye lens. Currently using nodes VideoIn > Undistort > ColorTracker > X&Y out.

I would get massive performance gain if I could go VideoIn > ColorTracker > X&Y out and then just do some undistort maths on this X&Y.

Can anyone help me or point me in the right direction please.


Hi again.

I’ve just continued digging around to find a solution to this and thought “of course, the maths is in the undistort.fx file!”. So I could do the calibration for the lens using the undistort(freeframe) node, then take the outputs, Distortion(4), Focal Lenth(2), Principal Point(2), and store them. Then put them into the same maths functions as in the effect file but instead of passing lots of X and Y positions of the texture to it, I can just pass one pair or co-ords throught it and get the corrected position.

I’m going to try and do this and I’ll update this thread with my results. I’m off to bed now thought.

If anyone has any thoughts on this I’d love to hear them.


maybe this helps a little to understand the math visually.

see here .