2011

Table Of Contents
(a) Axis node connected to two layers inside Reaction.
4-Point Tracking
In order to correctly project images onto televisions, bulletin boards, and other
quadrilaterals in an image sequence use the 4-Point tracking workflow.
With four-point tracking (also known as corner pinning), you use four trackers
to generate tracking data for anchoring the four corners of a bilinear surface
to background footage.
The reference points you use must be well-defined; it is recommended that
you plan them when shooting the sequence (for example, add markers to the
scene). It is not always possible to do four-point tracking when the reference
points are not well-defined.
In the following example, the goal is to pin an image of a jet to the screen of
a monitor as the camera moves.
NOTE You can also use the Reaction tool, and the position and translation
parameter controls of the Warp2D tool, and the position and translation vertices
parameter controls of the Garbage Mask, and Remove Dust tools.
4-Point Tracking | 777