THOMSON DD10, Installation Manual

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1. General Diamond digital
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1.6 KEY STAGES
1 or 2 key stages with border facilities are available in the individual mixing levels
for effects background designing or for caption insertion (chroma key), (lum key or
linear key). The priority can be changed (OVER).
The key stages are placed after the background mixing stage, set up in a cascaded
way and provided with taps for coupling in and out a signal for a DVE unit.
The downstream keyer (DSK) at the output of the switcher is identically designed
with regard to the key stages (2 key stages).
After the key stages, a facility is provided for fade to black (FTB). In DD5 and DD10
which do not dispose of a preset/program stage, only 1 downstream keyer is avail-
able for luminance or linear key.
For preview, a separate channel is available in the key stages, which can be con-
nected with equal input signals but different control signals. It is possible to preview
the next contribution (AUTO PREVIEW) or to make a transition without affecting
the program signal (TRANSITION PREVIEW).
For post-production, the layer mode permits to use the keyers as layers (DD20 and
DD30 only). The layers can be interchanged.
1.6.1 INPUTS/OUTPUTS
As key and fill signals, each keyer can dispose of more than 2 buses, and the DVE
bus of all inputs, the stores for video and key signals, and the central mattes. In
addition, own matte generators for fill and border are provided for each keyer.
For the downstream keyer in switcher DD5 or DD10, a bus with all inputs and the
signal of a matte generator are available as a fill signal.
Generation of the key signal is possible for each keyer from all inputs (SELF-KEY).
As internal key sources, wipe and mask signals are available. It is also possible to
feed a key signal modified by the DVE, into the key signal path (DVE LOOP).
In the setup mode, a key signal can be assigned to each fill signal, which has to be
switched together with selection of fill (couple). This assignment can optionally be
cancelled (split) in order to select another key signal.
As outputs, key or combined key signals, the signal of the key/mask store are avail-
able to the user via the AUX outputs. For preview purposes, the mask signal can
also be additively connected with the preview signal.
1.6.2 KEY VERSIONS
Chroma key
As a standard feature, a linear chroma key with foreground desaturation and back-
ground transition is realized.
Adjustment of the key parameters can be made automatically (for blue as key color
without measuring window, for other colors with measuring window) and can be
corrected manually.
The key signal can be also inverted (KEY INVERT).
The transparency (OPACITY) of each keyer can be adjusted separately.