NewTek Tricaster TCXD850, Руководство пользователя, Страница: 158 / 336

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The Background (BKGD) layer supplies
the ‘bottom-most’ video layer, seen
behind any other layers shown on
Program Out.
At any given moment BKGD may consist
of a mix of video streams from Program,
Preview and FX rows, or even a more
complex composition formed from the
numerous sources of one or more
Virtual Inputs.
8.2 VIDEO LAYERS
The concept of video layers is central to understanding how TriCaster’s Switcher and Transition
controls relate to one another, and how they combine to form the video seen on Program Out .
TriCaster TCXD850 clarifies the relationship of the video layers, and introduces the concept of the
Background layer (often shortened to simply ‘BKGD’).
Those familiar with other TriCaster models are accustomed to switching between the video
sources selected on the
Program and Preview rows, perhaps introducing one or two DSK (Down
Stream Keyer, over ‘overlay’) layers on top of that.
DSK layers are typically used for overlaying
graphics, titles, etc., though they may serve other
purposes as well.
The BKGD layer comprises the base video layer
upon which other layers are added.
It consists of the current combination of 1) video
output from the
Program row, 2) any portion of the
source selected on the Preview row that may
appear due to an incomplete transition, and 3) any
portion of the
FX source that appears by virtue of
chromakeying the Program and Preview sources.
Again, three other primary layers can contribute to TriCaster TCXD850’s Program output:

Two overlay layers, DSK 1 and DSK 2 , are c omposed above the BKGD layer on output.

DSK 2 appears ‘in front of’ DSK 1 on Program Output – that is, closest to the viewer.

FTB (Fade to Black) constitutes a final overlay layer – one that obscures all other layers
when applied.