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 area in the
frame is 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 usually 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 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 be more opaque, and lower values cause the gray areas to be
more transparent. Wholly black or white regions of the matte remain unaffected.
Invert
Selecting this checkbox inverts the matte, causing all transparent areas to be opaque and all
opaque areas to be transparent.
Solid Matte
Solid Mattes are mask nodes or images connected to the solid matte input on the node. The
solid matte is applied directly to the Alpha channel of the image. Generally, solid mattes are
used to hold out keying in areas you want to remain opaque, such as someone with blue eyes
against a blue screen.
Enabling Invert, inverts the solid matte before it is combined with the source Alpha.
Garbage Matte
Garbage mattes are mask nodes or images connected to the garbage matte input on the node.
The garbage matte is applied directly to the Alpha channel of the image. Generally, garbage
mattes are used to remove unwanted elements that cannot be keyed, such as microphones and
booms. They are also used to fill in areas that contain the color being keyed but that you wish
to maintain.
Garbage mattes of different modes cannot be mixed within a single tool. A Matte Control node
is often used after a Keyer node to add a garbage matte with the opposite effect of the matte
applied to the keyer.
Enabling Invert inverts the garbage matte before it is combined with the source Alpha.
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