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The Surface Tracker in action, overlaying the logo (left), and warping and conforming it realistically to the folds of the shirt (right).
Bounds
This is where you are prompted to draw an area on the image that you want to apply the texture to. Ideally, you want to choose a frame in the clip that has the surface you want to track as close and as flat-on to the camera as possible. This frame becomes the default reference frame for the effect. Make sure that the Open FX Overlay controls are active in the Viewer to use the tool. Simply click on the image to make multiple points around the area you want to define (a minimum of three points are required), and the effect will connect them automatically as a polygon. Boundary points should
be on the surface for tracking, not around it. If points are accidentally placed on object edges or the background instead, it will cause errors in the tracking.
You may add multiple boundaries and multiple holes to the same image, and all boundaries will join together into one shape before subtracting the holes. The purpose of multiple boundaries and holes are to allow you to mask out complex surfaces with regions not for tracking. For example, you can make a boundary around someone’s face, but use multiple holes to exclude the eyes and mouth
as those change appearance quickly as the subject blinks and talks, making them exceptionally difficult to track.
Multiple boundaries are designed to work on the same surface; using multiple boundaries on different surfaces within the image will cause poor results. Separate surfaces are best tracked by using multiple instances of the Surface Tracker instead.
The boundary is not useful for rotoscoping objects, only for analyzing the motion of a surface. Rotoscoping of foreground objects can be done as described in the Tracking Using a Mask section below.
— Click to Add Points: These are the controls used to make boundary areas on the image.
— Boundary: The currently selected boundary area on the image. You can change the current boundary or hole by using the drop-down menu. If there are issues with the boundary (i.e., crossed edges, too few points, etc.), an error message will appear next to the boundary name.
— + Bound: Adds a boundary polygon to the image. You can have multiple boundaries defined for the same surface, and they will be joined together into one shape.
— + Hole: Adds an area to exclude tracking from the surface. Used to remove overly complex and changing parts of a surface from the effect’s calculations.
— Delete: Lets you delete the boundary or hole selected in the Boundary field. Currently, this operation is not undo-able, so be careful around this button.
— Clear All: Lets you delete all boundaries and holes in the effect.