User Manual

Add a MatteControl node with a garbage mask to cut out the painted forehead.
TIP: When it comes to using masks to create transparency, there are a variety of ways
to connect one—for example, (a) attach the image to the background input of a
Brightness/Contrast node and attach a Polygon mask node to the effect mask input.
On the Brightness/Contrast node, enable the Alpha channel and lower the Gain slider
to darken a hole, or (b) using Channel Booleans to copy channel data to the alpha from
a Polygon node attached to the foreground input and the image attached to the
background input.
Drawing a Polygon Mask
After moving the playhead to the first frame of the clip, we’re ready to draw a mask to isolate
the “clean plate” forehead. Loading the MatteControl1 into the viewer and selecting the
Polygon1 node so that we see its tools in the viewer toolbar sets us up for drawing a polygon.
Drawing shapes using the Polygon node is similar to shape drawing in other spline-based
environments, including the Color page:
 Clicking once draws a corner control point.
 Clicking and dragging creates a Bézier curve.
 Clicking the first control point you created closes a shape.
We click and drag to create a shape that outlines the man’s forehead, and when we close the
shape, we see exactly the opposite of what we want, a hole in the middle of the image.
Drawing a shape to isolate the forehead gives an inverted result at first when using the
Garbage Matte input of the MatteControl node to attach the Polygon to the MatteControl node.
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