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.
oPCR: 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.
oMIP: 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.
oCOARSE: 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.
oVBR: 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.
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