Four corner pin tracking and barrel (lens) distortion

Support Compositing and Post Processing
1

Hi everyone,

I want to do a four corner pin tracking, like this: http://vimeo.com/25516157
In my footage I have a television, where I have to put the other material.
Everything works fine, except that I want to add some barrel distortion to the television screen, like this: http://www.arielnet.com/Main/images/fig1f.gif

Lens distortion node produces more or less the same effect, except that it can only apply distortion to the whole image, but I only want it to affect the TV screen.

Adding more vertices and subdividing is kind of a no go, because the 4 corner of the plane is hooked to the empties, that are placed where the markers were, so the additional vertices wouldn’t move with the plane.

Do you guys have any suggestions how to do this?
Thanks!

Regards,
marchello

2

Try distorting the mesh with modifier Cast (as sphere) or pre-distorting the footage that goes into the pinned object.

3

thanks 3pointEdit.
actually I found what caused the problem. what I first thought of, the barrel distortion was actually turned out to be a simple lens distortion and undistorting the footage, compositing, and distorting it again solved the problem.