Applying Filters to Masks
As with shapes, you can apply filters to masks, which remain editable even after the
application. It’s an extremely powerful way to further manipulate the alpha channel
created by a mask.
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For example, you can apply the Crystallize filter to a mask to stylize its edges. This results
in jagged edges that resemble facets of crystal around the edges.
Original mask (color channel)
Original mask (alpha channel)
Crystallize filter applied to alpha channel
(color channel view)
Crystallize filter applied to alpha channel
(alpha channel view)
When applying filters to masks, it’s useful to bear in mind that masks are just grayscale
images. In the example above, the Crystallize filter creates patterns in the grayscale mask
image, which results in a rippled translucent pattern.
To apply a filter to a mask
Do one of the following:
µ
Drag a filter from the Library onto a mask in the Layers list or Timeline.
µ
Select a mask in the Layers list or Timeline, then choose a filter from the Add Filter pop-up
menu in the toolbar.
The filter appears nested underneath the mask layer to which it’s applied.
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