Reference Manual
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The
Video/Audio
tab also has a button for restarting the Decoder. You do not
have to press this button after clicking “Save & Apply”, applying the changes
will automatically restart the Decoder. But it might be handy during normal
operation, if you feel the need to restart the decoder.
3.5.3
Evaluation
The
Evaluation
tab holds options to measure the latency of the video stream.
These features are specific to Targa and only work, if the transmitter is a
Targa Transmitter and the feature is enabled on both devices.
To measure the latency, a barcode is stamped into the top right corner of
each frame. This barcode encodes the time when the frame was captured.
The receiver will then evaluate this barcode after displaying the frame and
display the latency in its status tab. For this feature to work correctly, the
clocks of both devices have to be synchronized. This can be done by
connected both devices to a NTP server (see chapter 3.2.1). Alternatively the
transmitter can periodically send its local time to the receiver, which can than
calculate the offset between the clocks. The second method is not as
accurate though, because it cannot measure the network latency.
The following table sums up the settings:
Setting
Description
Default
Latency
Measurement
Enables evaluation of the timestamp
barcode.
Disabled
Use Time
Server
Optionally use the data supplied by the
Transmitter’s time server, if the clocks of
sender and receiver are not in sync.
Disabled
Time Receiving
Port
UDP Port of the Receiver which is used to
receive the packets. Only needed if the
Time Server is used.
5010
Out-Of-Order
count
Checks an additional barcode, to check
for out of order frames. This is generally
not needed, as the RTP protocol used to
transmit the video streams automatically
Disabled
