Autodesk 62205-051408-9001 User Guide - Page 698

About Tracking, what the Tracker can do, and you find new ways

Page 698 highlights

26 Tracking The flexibility of the Tracker makes it more of a medium than simply a tool. As you gain experience you begin to see the implications of what the Tracker can do, and you find new ways to achieve the kind of effects you want to accomplish. About Tracking The Tracker is a tool for following and capturing the motion of an on-screen feature, and then applying that stored motion to a second element, so that the two appear to be "locked" together. You can track any number of features in a clip: • In 1-point tracking, you track a single feature for position. • In 2-point tracking, you track two features, using the relationship between the two to track scale/ rotation. • In 4-point tracking (more commonly referred to as corner pinning), you track four features. • In multiple-point tracking, you track as many features as you want. You can apply the stored motion to various elements: • You can apply the motion to the center point of an object. For example, you could track a halo over the head of a person in a clip. Assume that in the clip a woman tilts her head and advances toward the camera. You would want the halo to reflect the position, scaling, and rotational changes of the tracked features on the woman's head. Note: When you track scaling with Combustion, you are not performing "3D tracking" in true Z-space. You are simply measuring the amount of change over time in the size of the tracked object. • You can apply the motion to each of the control points of an object. The shape of the object changes to reflect the motion of the reference feature its control points are locked to. For example, if you want to replace the label on an actor's clothing, each corner on the new label would track a corner on the old label. The shape of the new label would change to correspond to those movements. • You can apply the motion to the center point of a filter. For example, you may want the center point of a lens flare filter to track the motion of a street lamp. • You can apply the motion to a Stabilize filter, which removes the motion from the clip. In this case, you would track unwanted motion in the clip. Note that the Tracker is not limited to composites, as there are many useful applications for it in Particles and Paint as well. For example, if you want to do wire removal, you can have a cloned paint stroke tracked to the wire. 682

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Tracking
26
682
The flexibility of the Tracker makes it more of a
medium than simply a tool. As you gain
experience you begin to see the implications of
what the Tracker can do, and you find new ways
to achieve the kind of effects you want to
accomplish.
About Tracking
The Tracker is a tool for following and capturing the
motion of an on-screen feature, and then applying
that stored motion to a second element, so that the
two appear to be “locked” together.
You can track any number of features in a clip:
In 1-point tracking, you track a single feature for
position.
In 2-point tracking, you track two features, using
the relationship between the two to track scale/
rotation.
In 4-point tracking (more commonly referred to as
corner pinning), you track four features.
In multiple-point tracking, you track as many
features as you want.
You can apply the stored motion to various elements:
You can apply the motion to the center point of an
object. For example, you could track a halo over the
head of a person in a clip. Assume that in the clip a
woman tilts her head and advances toward the
camera. You would want the halo to reflect the
position, scaling, and rotational changes of the
tracked features on the woman’s head.
Note:
When you track scaling with
Combustion
, you
are not performing “3D tracking” in true Z-space. You
are simply measuring the amount of change over
time in the size of the tracked object.
You can apply the motion to each of the control
points of an object. The shape of the object changes
to reflect the motion of the reference feature its
control points are locked to. For example, if you
want to replace the label on an actor’s clothing, each
corner on the new label would track a corner on the
old label. The shape of the new label would change
to correspond to those movements.
You can apply the motion to the center point of a
filter. For example, you may want the center point
of a lens flare filter to track the motion of a street
lamp.
You can apply the motion to a Stabilize filter, which
removes the motion from the clip. In this case, you
would track unwanted motion in the clip.
Note that the Tracker is not limited to composites, as
there are many useful applications for it in Particles
and Paint as well. For example, if you want to do wire
removal, you can have a cloned paint stroke tracked
to the wire.