T-VIPS CP525 cMux, User Manual

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WEB Interface 147
ID: um_tsmux CP525 cMux User’s Manual Rev. 5.20.12 (3944)
Pref. Init. Rate Mode
From the pull-down list select the preferred algorithm to find the initial bitrate of a received
data stream.
PCR
The default mode is PCR , in which case a number of consecutive TS packets of the
first PCR PID encountered are used to calculate the bitrate. If no PCR PID is found
simple bitrate measurement over a couple of seconds is used.
VBR
In this mode the unit attempts to read data from the input buffer at the rate entered in
the Max VBR bitrate input. If the incoming rate is higher than this a buffer overflow
alarm will be triggered.
FAST COARSE
In this mode the units attamps to set up the regulator very fast on the expense of
possible jitter on the output. For ASI output this may initially create jitter outside of
the specification and should only be used when having IP -
>
IP transmission.
Expected PCR accuracy
The expected clock accuracy of the PCR in the input signal. The configured value affects
how far off the initial bitrate (determined from the incoming PCR) the buffer regulator
may adjust the output bitrate to compensate for input latency. The default value (25ppm)
should be sufficient to handle signals from professional DVB equipment at the same time
guaranteeing that the output bitrate does not deviate beyond 25ppm. If you want to
synchronise to streams coming from sources with less accurate clocks, you may have to
configure a wider operation range to allow the output clock to be tuned further off to avoid
buffer over-/underflow.“
Max bitrate
If VBR rate mode is chosen this parameter tells the unit the bitrate to use when reading
from the input buffer.
The Re-sync Conditions field:
Bitrate change
Checking this box will make the unit re-synchronise faster in the case of small bitrate
changes. PCR based bitrate measurements deviating 100ppm or more from the initially
determined bitrate causes immediate buffer re-synchronisation.
Latency limits (rel. to pref.)
Checking this box will make the unit re-synchronise if the measured latency exceeds the
configured limits set in the configured preferred latency.
The
Regulator Status
field allows inspecting the status of the buffer regulator.
Regulator state
This parameter shows the current state of the buffer regulator. The possible states are
Stopped , Rate Estimation , Coarse and Finetune . When data is received and an initial
bitrate estimate is found the regulator enters the
Rate Estimation
state, where the signal is
analysed to check if a better estimate of the bitrate can be found. When a better estimate