2011

Table Of Contents
Drop Alpha
The Drop Alpha tool is a simple matte modifier that drops the alpha channel
from its primary input. This tool has no control parameters but always outputs
an RGB image.
NOTE This implies that if the input is an alpha-only image, the output will be a
black RGB image.
Edge Tool
The Edge tool is one of the tools used for matte cleanup tasks during the keying
process. It lets you shrink, erode, or blur the edge of the matte, as well as
isolate the edge of the matte, or invert the matte.
Because the Edge tool affects the alpha and is applied to the output of a keyer
tool, such as the Luma Keyer or the Diamond Keyer, your dependency graph
should include, as a minimum, a source and a keyer.
The Edge tool contains the following parameters:
To:Use:
Isolates the edge of the key. The numeric field takes values representing
the width of the detected edge based on a 0% to 100% float. Edge
width can depend on image size.
Edge Detect
Invert the matte.Invert
Reduce the edge width. The numeric field takes values representing the
pixel width of the shrink filter (from 0.000 to 30.000 float).
Shrink
Blend (soften) the light and dark edges. The numeric field takes values
representing the pixel width of the erode filter (from 0.000 to 30.000
float).
Erode
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