Unfortunately, this warping will effectively reduce the resolution of the image by half, so rendering must be accomplished at twice the normal size. We typically ignore the effects of lens distortion unless it is particularly bad. The camera solution will have some built in error, but we have ways of dealing with that. Other Problems Other things can get in the way of a good track. A film set is a dynamic, busy place.
Actors can walk in front of all the good tracking features in the set.
The camera might be moving fast enough so that all the points are motion blurred. The lighting during a shot can change so significantly that automatic tracking methods fail. Problems such as these highlight the difference between typical computer vision applications and computer vision in visual effects. Our computer vision problems do not need to be real-time solutions and if they are not perfect the first time around, the artist can nudge the solution until it s correct. 2D tracking was used to apply digital makeup to Brad Pitt in Interview with a Vampire.