High End Systems CATALYST DV, Руководство пользователя

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CHAPTER 6
Media Playback
42
Catalyst® V3 Media Server User Manual
Referencing Content with the Use Layer
By setting a layer’s Library parameter DMX value to 254, you can then use the File
parameter’s DMX value to select another layer’s content to use in place of an actual file.
The DMX value of the
File parameter directly corresponds to the layer number (1-4 for
example). This turns the first layer into a reference layer , an “alias” of the selected layer’s
file—that is, a duplicate instance of the file playing on the selected layer. You can
reposition and apply different effects to either instance, but playback controls work only
on the
reference layer , not the selected layer.
For example, suppose you want layers 1 and 2 to
contain the same image positioned differently on
the screen. First, you would select the image and
assign it to Layer 1 normally, then you would
assign Layer 2 to reference Layer 1. Each layer
shows the same image, but you can move each
instance on the screen independently.
Reference layers lighten system load, especially
hard disk access. Though you manipulate the
referenced file in different ways on different
layers, the Catalyst system needs to read that file
from the hard drive only once. If you were to assign the same movie file independently to
each layer, the Catalyst system has to read the file multiple times.
In Frame and Out Frame
You can select a segment of a movie file for playback by assigning an In Frame as a start
point and an Out Frame as an end point.
The In Frame parameter corresponds to a 16-bit DMX value equal to a starting frame of
the selected movie file. Similarly, The Out Frame parameter corresponds to a 16-bit DMX
value equal to an ending frame of the selected movie file. Assigning the In Frame and Out
Frame parameter DMX values to 0 will playback the entire movie file.
Movie
beginning
frame
Movie
ending
frame
Movie segment In Frame
parameter
setting
Out Frame
parameter
setting