Avid Technology Digidesign USD, Руководство пользователя, Страница: 52 / 96

Universal Slave Driver 48
stream. Thus, VITC is never inserted when
the Positional Reference is set to VITC or
Auto Switch LTC/VITC.
Example Video Input Configuration
One common situation is transferring
video from a source VTR (or a nonlinear
video editing system) to a destination VTR
(or a nonlinear video editing system). The
video source signal is connected to one of
the USD’s video input connectors accord-
ing to the VITC Video Source rule.
The USD Video Out signal is connected to
the destination device. The USD is then
able to stripe the second VTR’s videotape
with VITC. (At the same time, you might
also want to insert a window burn, as de-
scribed in “Window Burn Display Options”
on page 53.)
▲ Unlike LTC, the USD can regenerate VITC
with both forward and reverse time code ad-
dresses.
To prevent destruction of the original VITC
code, the USD will not re-apply (regener-
ate) VITC onto the same video stream from
which it is reading VITC.
LTC If you want to use LTC as a positional
source, do not select Auto Switch
LTC/VITC.
External
In order for the USD to regenerate
VITC based on an external positional refer-
ence, you’ll need to select both a clock ref-
erence and a positional reference.
To regenerate VITC based on an external
positional reference from the front panel:
1
Connect the video source to the USD
Video Ref connector and loop to the USD
Video Input connector.
2
Select VITC Insertion (VI7C In5), using
the Set, Down, and Up switches.
3
Press the Set switch again. The LED Time
Code Display displays one of the two pa-
rameter values (On or OFF).
4
Use the Down and Up switches to switch
between the parameter values.
5
Press Set to select VITC Insertion.
6
Make sure you have selected the appro-
priate format (NTSC or PAL, depending on
your project). For instructions, see “Video
Format/System” on page 60.
7
Use Set, Up and Down to access the VITC
Generate Lines (6En LInE) parameter. Press
the Set switch again. The default line pair
is14/16, which is also the SMPTE-recom-
mended setting.
8
Use the Down and Up switches to scroll
through the parameter values and select a
new VITC line pair, if necessary. When you
have chosen your desired line pair, press
Set. The LED Time Code Display will return
to showing time code numbers.
9
Select valid clock and positional refer-
ences.
The USD will now regenerate VITC and in-
sert it onto the video signal (as soon as it re-
ceives a valid positional reference signal).