User Manual

Clipping Mode
This option determines how edges are handled when performing domain of definition
rendering. This is profoundly important when blurring the matte, which may require samples
from portions of the image outside the current domain.
 Frame: The default option is Frame, which automatically sets the node’s domain of
definition to use the full frame of the image, effectively ignoring the current domain
of definition. If the upstream DoD is smaller than the frame, the remaining areas in the
frame are treated as black/transparent.
 Domain: Setting this option to Domain respects the upstream domain of definition
when applying the node’s effect. This can have adverse clipping effects in situations
where the node employs a large filter.
 None: Setting this option to None does not perform any source image clipping at all.
This means that any data required to process the node’s effect that would normally be
outside the upstream DoD is treated as black/transparent.
Contract/Expand
This slider shrinks or grows the semitransparent areas of the matte. Values above 0.0 expand
the matte, while values below 0.0 contract it.
This control is usually used in conjunction with the Matte Blur to take the hard edge of a matte
and reduce fringing. Since this control affects only semitransparent areas, it has no effect on a
matte’s hard edge.
Gamma
Matte Gamma raises or lowers the values of the matte in the semitransparent areas. Higher
values cause the gray areas to become more opaque, and lower values cause the gray areas to
become more transparent. Completely black or white regions of the matte remain unaffected.
Since this control affects only semitransparent areas, it will have no effect on a matte’s
hard edge.
Threshold
This range slider sets the lower threshold using the handle on the left and sets the upper
threshold using the handle on the right.
Any value below the lower threshold setting becomes black or transparent in the matte.
Any value above the upper threshold setting becomes white or opaque in the matte. All values
within the range maintain their relative transparency values.
This control is often used to reject salt and pepper noise in the matte.
Restore Fringe
This restores the edge of the matte around the keyed subject. Often when keying, the edge of
the subject where you have hair is clipped out. Restore Fringe brings back that edge while
keeping the matte solid.
Invert Matte
When this checkbox is selected, the Alpha channel created by the keyer is inverted, causing all
transparent areas to be opaque and all opaque areas to be transparent.
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