User Manual

Detail(-)
When this button is selected, foreground detail becomes more visible for the sampled pixel
color (and all colors like it) in the amount of one Primatte increment. If detail is still missing,
another click using this operational mode tool makes detail more visible. This can be used to
restore lost smoke or wisps of hair. Sample where the smoke or hair just disappears and it
returns to visibility. Use this for restoring color regions that were moved into the 100%
background region. It may start to bring in background noise if shooting conditions were not
ideal on the foreground image.
Algorithms
There are three keying algorithms available in the Primatte keyer:
 Primatte: The Primatte algorithm mode delivers the best results and supports both the
Solid Color and the Complement Color spill suppression methods. This algorithm uses
three multifaceted polyhedrons (as described later in this section) to separate the 3D
RGB colorspace. It is also the default algorithm mode and, because it is computationally
intensive, it may take the longest to render.
 Primatte RT: Primatte RT is the simplest algorithm and therefore the fastest. It uses only
a single planar surface to separate the 3D RGB colorspace (as described later in this
section) and, as a result, does not separate the foreground from the backing screen
as carefully as the above Primatte algorithm. Another disadvantage of the Primatte
RT algorithm is that it does not work well with less saturated backing screen colors, and
it does not support the Complement Color spill suppression method.
 Primatte RT+: Primatte RT+ is in between the above two options. It uses a six planar
surface color separation algorithm (as described later in this section) and delivers
results in between the other two options in both quality and performance. Another
disadvantage of the Primatte RT+ algorithm is that it does not work well with less
saturated backing screen colors, and it does not support the Complement Color spill
suppression method.
Hybrid Rendering
After sampling the backing screen color and producing acceptable edges around the
foreground object, you sometimes find a transparent area within the foreground subject. This
can occur when the foreground subject contains a color that is close to the backing screen
color. Removing this transparency with the Clean FG Noise mode can cause the edge of the
foreground subject to pick up a fringe that is close to the backing screen color. Removing the
fringe is very difficult without sacrificing quality somewhere else on the image. The Hybrid
Render mode internally creates two keying operations: Body and Edge. The optimized Edge
operation gets the best edge around the foreground subject without any fringe effect. The
Body operation deals with transparency within the foreground subject. The resultant matte is
created by combining these two mattes, and then blurring and eroding the foreground subject
in the Body matte and combining it with the edge matte.
To use Hybrid Rendering, start by keying the main foreground area using the Select
Background Color mode (or any of the other Primatte backing screen detection methods).
Activate the Hybrid Rendering checkbox. Lastly, select the Clean FG Noise button and scrub
over the transparent area. The Hybrid Render mode performs the “Body/Edge” operation. The
result is a final composite with perfect edges around the foreground subject with a solid
foreground subject.
Hybrid Blur
Blurs the Body matte that has been automatically generated when Hybrid Rendering is
activated.
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