User Manual

Introduction to Tracking
Tracking is one of the most useful and essential techniques available to a compositor. It can be
roughly defined as the creation of a motion path from analyzing a specific area in a clip over
time. Fusion includes a variety of different tracking nodes that let you analyze different kinds of
motion. Once you have tracked motion on a clip, you can then use the resulting data for
stabilization, motion smoothing, matching the motion of one object to that of another, and a host
of other essential tasks.
Types of tracking nodes in Fusion:
 Tracker: Follows a relatively small, identifiable feature or pattern in a clip to derive a 2D
motion path. This is sometimes referred to as point tracking.
 Planar Tracker: Follows a flat, unvarying surface area in a clip to derive a 2 ½D motion
path including perspective. A planar tracker is also more tolerant than a point tracker
when some tracked pixels move offscreen or become obscured.
 Camera Tracker: Tracks multiple points or patterns in a clip and performs a more
sophisticated analysis by comparing those moving patterns. The result is a precise
recreation of the live-action camera in virtual 3D space.
Each tracker type has its own chapter in this manual. This chapter covers the tracking
techniques with the Tracker node.
Tracker Node Overview
The Tracker node is a single node that actually performs tracking, stabilizing, matching moving,
and corner-pinning operations. Since the Tracker node can transform the foreground input, it
can be used to generate tracks and then operate as a Merge in a match move or corner-pin
setup. Or you can use it to produce tracking data only and then publish that data to other nodes
in the Node Editor.
Modes of the Tracker Node
The Tracker node is an incredibly flexible tool often used multiple times in a composite to help
with dozens of tasks. However, most of those tasks can be boiled down into just a few
operations. The Tracker node has four operation modes that cover the majority of tracking
situations.
Stabilizing
You can use one or more tracked patterns to remove all the motion from the sequence or to
smooth out vibration and shakiness. When you use a single tracker pattern to stabilize, you
stabilize only the X and Y position. Using multiple patterns together, you are able to stabilize
position, rotation, and scaling.
Match Moving
The reverse of stabilizing is match moving, which detects position, rotation, and scaling in a clip
using one or more patterns. Instead of removing that motion, it is applied to another image so
that the two images can be composited together.
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