Using the Matte Choker effect

The following procedure provides a basic overview of how to use this effect.

To close a hole in a matte:

1. Select the layer, and choose Effect > Matte Tools > Matte Choker.
2. Set stage-one controls (the first three sliders) to spread the matte as far as possible without altering its shape, as follows:
• Geometric Softness specifies (in pixels) the largest spread or choke.
• Choke sets the amount of choke. Negative values spread the matte; positive values choke it.
• Gray Level Softness specifies how soft to make the edges of the matte. At 0%, the matte edges contain only fully opaque and fully transparent values. At 100%, the matte edges have a full range of gray values, but may appear blurred.
3. Set stage-two controls (sliders four, five, and six) to choke the matte by the same amount you spread it in stage one.
4. (optional) Use the Iterations slider to specify how many times After Effects repeats the spread-and-choke sequence. You may need to try a few different settings so that the sequence is repeated as many times as necessary to close any unwanted holes.