2011

Table Of Contents
NOTE If the input image has no alpha channel, one will be added. This is consistent
with Composite's general behavior with respect to missing channels. A missing
alpha channel is interpreted as a virtual solid opaque alpha channel.
Invert Alpha
The Invert Alpha tool inverts the alpha channel of its primary input and has
no control parameters. The Invert tool is already capable of inverting the alpha
channel of its primary input. However, Invert Alpha can achieve this without
the need to select the proper affect target and makes the Schematic easier to
understand.
Median Alpha
The Median Alpha tool is almost identical to the Median Tool (see
Median
Tool
on page 406) and is excellent for removing impulse noise, but is designed
to operate on the alpha channel of the input image.
It has all the parameters of the Median tool except for the Criteria parameter,
which is not needed because this tool always computes the median value by
ranking the alpha value of each pixel.
NOTE This tool affects only the alpha channel.
Remap Alpha
The Remap Alpha tool lets you remap the alpha using a single curve
manipulation interface similar to Blend Curves. The curve defaults to the
identity mapping.
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