Network Technologies DVB-ASI to IP - Manual (Page 52)

ASI-IP-GTW User's Manual
Page 52
3.7.5 Advanced Tab
Figure 24 Advanced Tab
On the advanced tab it is possible to control and inspect the status of
the buffer regulator for a port.
Pref. Init. Rate Mode: This parameter is used to select the preferred
algorithm to use to find an initial bitrate for a received data stream.
o PCR:
The default mode is ‘PCR’, in which a number of consecutive
TS packets on the first PCR PID encountered are used to calculate
the bitrate. If no PCR PID is found, COARSE mode is
automatically used.
o MIP:
This mode may be used for signals that do not contain any
PCR PIDs, but do have a DVB MIP PID (PID 21) used in Single
Frequency Networks. In MIP mode, two consecutive MIP packets
are used to estimate the bitrate. If no MIP PID is found, COARSE
mode is automatically used.
o COARSE:
In this mode, a simple 2 second measurement is used to
estimate the bitrate. This method is sensitive to network jitter and
does not give as good results as PCR and MIP mode.
o VBR:
In this mode, the unit attempts to transmit data at the rate
entered in the Max bitrate input. If the incoming rate is lower than
this, the unit will either pad with idle bytes (resulting in a VBR
output stream) or with NULL packets, depending on whether the
“Pad with NULL packets” checkbox is checked. In this mode, no
PCR adjustment is performed.