Autodesk 62205-051408-9001 User Guide - Page 700

26 Tracking X & Y-Tracks both the horizontal and vertical motion of the reference feature. X Only-Tracks only the horizontal motion of the reference feature. For example, when stabilizing a clip, you could track only the horizontal (X) motion to remove horizontal camera jitter, while keeping the vertical (Y) motion, which is intended to be present in the clip. Y Only-Tracks only the vertical motion of the reference feature. For example, say you have an image of a feather you want to track to the vertical (Y) motion of a leaf falling. Assume you do not want the feather to follow the side-to-side (X) motions of the leaf as it falls. You would restrict the Tracker to following the Y motion. Mode Use the Mode options to indicate whether or not to keep any spatial offset that exists between the center of the reference box and the pivot point of the object or layer. Absolute-Eliminates any offset. For example, in the following illustration, the ellipse is tracking the position of the asterisk. When the analysis started, the pivot point of the ellipse was automatically positioned to coincide with the center of the reference box on the asterisk. ellipse remains offset from the center of the reference box on the asterisk. Parent to Source This button is equivalent to manually parenting the "tracked-to" (child) clip to the "tracked" (parent) clip after tracking. Note: This option is available only when tracking in a composite. Before using the Tracker, examine the relationship between the objects tracked to and being tracked. If there are no existing parent-child hierarchies, and you want the tracked layer to later respect any positioning, rotating, scaling, shearing, or pivoting adjustments that you make to the tracked object, click Parent to Source. For example, say you need to track a small burning red coal onto the tip of a cigarette in an actor's mouth. You know that the clip will later need to be scaled and positioned, so you click Parent to Source before the Tracker begins to analyze. This ensures that any later changes made to the "actor smoking" clip will also be copied down to the child (glowing coal clip) layer. Relative-Maintains any spatial offset that exists between the reference feature and the object or layer. This is the default setting. Here the pivot point of the Reference List Use the Reference options to indicate whether or not to update the reference at each frame. Fixed-Leaves the contents of the reference box unchanged during tracking. This is faster than 684