MacroSystem Bluebox World - Manual (Page 17)

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6.3.1-9 Luma 2
As with “Luma 1“, the only selection criteria
for “Luma 2“ is the brightness of the image.
However, whereas under “Luma 1“ a selected
range of brightness is made transparent within
a specific tolerance range, “Luma 2“ functions
like a limit switch. Regions of the image whose
brightness is less than that of a specified
brightness threshold become transparent,
whereas all the image regions above this
brightness threshold remain visible.
Two settings have to be made:
• Threshold
The brightness threshold is specified by means
of the “Threshold“ slider. The foreground
scene remains visible below the specified
threshold, whereas it becomes transparent
above this threshold.
• Mode
When “smaller“ is set, all the brightness values
above the set threshold become transparent. In
the “higher“ mode, the entire foreground video
is initially transparent, and certain brightness
values only become visible when past the set
threshold.
6.3.1-10 Saturation 1
The function and application correspond to
those of “Luma 1“, but the color saturation is
used instead of the brightness.
6.3.1-11 Saturation 2
The function and application correspond to
those of “Luma 2“, but the color saturation is
used instead of the brightness.
6.3.1-12 Black
The “Black“ mode allows black components
of the foreground scene to be removed. This
function is particularly interesting for special,
ready-made video material (“super-black
animations“), where the background be shown
in what is called “super-black“, a particularly
deep black for “super-black“ Bluebox effects.
One setting has to be made:
• Tolerance
The “Tolerance“ slider specifies how far the
black value may diverge from“ideal super-
black“.
6.3.2 Select Area
Allows both an active and an inactive region of
the foreground video to be selected. The rele-
vant Bluebox effect operates within the active
area. No changes are made areas outside the
active area. It is possible to define yet another
inactive area within the active area. This area is
then also excluded from execution of the effect.
In order to clarify the functioning of active and
inactive areas with the aid of an example, ima-
gine one scene showing a fire in a fireplace and
another scene containing a blue sky and blue
ocean. A person with blue eyes stands in the fo-
reground of the ocean scene, and looks into the
camera. You would now like to replace the sky
by the fire, which means making the sky transpa-
rent so that the fire appears in place of the sky.
The problem that initially stands in the way of
this idea is that the sky and the ocean differ only
slightly in color, so that Bluebox technology may
affect them both. For this reason, the ocean must
be excluded from the effect, by defining the sky
as the only active region. The Bluebox effect only
operates in the region of the sky, while the other
regions remain unaffected. We now have the
problem of the blue-eyed person in front of the
blue sky. The Bluebox effect would automatically
allow the fire to shine through the person‘s blue
eyes, if it were not for an additional inactive re-
gion. You place this area over the person‘s eyes,
and now only the sky is given modified colors.
The following settings can be made:
• Full Images
Area selection does not operate if “Full Images“
is selected. The effect is then applied to the
whole area of the screen. In order to set the “In-
clude Area“ and the “Exclude Area“ it is neces-
sary to remove the check from “Full Images“
(by a single click with the trackball). The initial
setting for this value is “Full Images: active“.
• Include area
A rectangle whose position and size can be
freely selected precisely encloses the area of
the front video image that is to be subjected to
the effect.
• Exclude area
A rectangle whose position and size can be
freely selected encloses any area within the pre-
viously selected active area. This second area
will be excluded from execution of the effect.