NewTek TriCaster TC1 (2 RU) User Manual
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F
RAME
S
YNC
By default,
Frame Sync
is set to
Automatic
for all
external source types, allowing you to work with a wide
array of potential video sources without concerns
about video timing.
This option
(Automatic
) enables the full array of timing correction tools available to achieve smooth and
accurate fr
ame timing in your productions, including features that correct for issues caused by ‘less than
ideal’ networks.
The next menu option (
On
) enables full-time frame synchronization and may well suffice in some video
pipelines. This alternative has the benefit of ensuring the lowest throughput latency possible on a video
switcher using frame-sync (2-3 frames).
The final
Frame Sync
option is
Off
. Disabling
Frame Sync
altogether ensures the very lowest possible
throughput latency for genlocked sources. Note that sources with
Frame Sync
disabled
must
be genlocked,
and in phase (that is within 180° of the current
Switcher
output). Otherwise, video from the source will
simply not seen. In practice, disable
Frame Sync
for genlocked sources only, then adjust the
Phase
setting
(see Section 8.2.2) until video is displayed and you should be all set.
P
REMULTIPLIED
A
LPHA
FIGURE 70
If you are supplying imagery (video sources, video clips, or still images) that support transparency by means
of an embedded alpha channel, your choice here will be important.
There are two ‘flavors’ alpha channel
pixel encoding. The first is often called
‘straight’, or may be referred to as ‘
non-premultiplied
’.
Unsurprisingly, the alt
ernative is ‘premultiplied’.
The
Premultiplied Alpha
switch is off by default. Making the correct selection is necessary for correct
compositing over other imagery.
L
OW
B
ANDWIDTH
FIGURE 71
For NDI sources, a
Low Bandwidth
option is shown. This allows you to force the sending device to a lower
quality video stream that may nevertheless be quite useable if the source is not intended to be displayed full
screen. This option may be preferable in network settings with limited capacity (such as WiFi).
FIGURE 69