[Live-devel] QoS with openRTSP and Jitter output

[David Wendel]

Hello List,

in my "IPTV QoS Monitoring" project i've tried to use openRTSP to get
QoS information for a particular stream. The output of jitter as a QoS
parameter is also interesting for me, so I'v extended the openRTSP code
to output this information. My question is, if I did it the right way,
because the jitter value I get, seems to be strange to me. So here is
the way I did it, I'v modified the 'live/testProgs/playCommon.cpp' by
adding two lines after the line number 1128 and 1142, see below:

  1126  #ifdef SUPPORT_REAL_RTSP
  1127          if (session->isRealNetworksRDT) {
  1128            RealRDTSource* rdt = (RealRDTSource*)src;
  1129            *env << "jit_ms\t" << rdt->jitter()/1000.0 << "\n";
  1130            *env << "ipg_ms_min\t" <<
rdt->minInterPacketGapUS()/1000.0 << "\n";
  1131            struct timeval totalGaps = rdt->totalInterPacketGaps();
  1132            double totalGapsMS = totalGaps.tv_sec*1000.0 +
totalGaps.tv_usec/1000.0;
  1133            unsigned totNumPacketsReceived =
rdt->totNumPacketsReceived();
  1134            *env << "ipg_ms_avg\t"
  1135                 << (totNumPacketsReceived == 0 ? 0.0 :
totalGapsMS/totNumPacketsReceived) << "\n";
  1136            *env << "ipg_ms_max\t" <<
rdt->maxInterPacketGapUS()/1000.0 << "\n";
  1137          } else {
  1138  #endif
  1139            RTPReceptionStatsDB::Iterator
statsIter(src->receptionStatsDB());
  1140            // Assume that there's only one SSRC source (usually
the case):
  1141            RTPReceptionStats* stats = statsIter.next(True);
  1142            if (stats != NULL) {
  1143               *env << "jit_ms\t" << stats->jitter()/1000.0 << "\n";
  1144              *env << "ipg_ms_min\t" <<
stats->minInterPacketGapUS()/1000.0 << "\n";
  1145              struct timeval totalGaps =
stats->totalInterPacketGaps();
  1146              double totalGapsMS = totalGaps.tv_sec*1000.0 +
totalGaps.tv_usec/1000.0;
  1147              unsigned totNumPacketsReceived =
stats->totNumPacketsReceived();
  1148              *env << "ipg_ms_avg\t"
  1149                   << (totNumPacketsReceived == 0 ? 0.0 :
totalGapsMS/totNumPacketsReceived) << "\n";
  1150              *env << "ipg_ms_max\t" <<
stats->maxInterPacketGapUS()/1000.0 << "\n";
  1151            }
  1152  #ifdef SUPPORT_REAL_RTSP
  1153          }
  1154  #endif

Here is an output example I get vor video and audio separatly:

[24.05.2007 14:36:25]: Created receiver for "video/X-ASF-PF" subsession
(client ports 1046-1047)
[24.05.2007 14:36:25]: Setup "video/X-ASF-PF" subsession (client ports
1046-1047)
[24.05.2007 14:36:25]: Outputting data from the "video/X-ASF-PF"
subsession to 'stdout'
[24.05.2007 14:36:25]: Started playing session
[24.05.2007 14:36:25]: Receiving streamed data (for up to 25.000000
seconds)...
[24.05.2007 14:36:25]: Data packets have begun arriving [1180017360988]
[24.05.2007 14:36:25]: begin_QOS_statistics
[24.05.2007 14:36:25]: server_availability      100
[24.05.2007 14:36:25]: stream_availability      100
[24.05.2007 14:36:25]: subsession       video/X-ASF-PF
[24.05.2007 14:36:25]: num_packets_received     564
[24.05.2007 14:36:25]: num_packets_lost 0
[24.05.2007 14:36:25]: sdur_sec 25.007102
[24.05.2007 14:36:25]: trans_kB_tot     4110.460000
[24.05.2007 14:36:25]: measurement_sampling_interval_ms 100
[24.05.2007 14:36:25]: kbps_min 0.000000
[24.05.2007 14:36:25]: kbps_avg 1314.973642
[24.05.2007 14:36:25]: kbps_max 4294.319547
[24.05.2007 14:36:25]: loss_percent_min 0.000000
[24.05.2007 14:36:25]: loss_percent_avg 0.000000
[24.05.2007 14:36:25]: loss_percent_max 0.000000
[24.05.2007 14:36:25]: jit_ms   0.064000
[24.05.2007 14:36:25]: ipg_ms_min       0.053000
[24.05.2007 14:36:25]: ipg_ms_avg       43.969628
[24.05.2007 14:36:25]: ipg_ms_max       735.418000
[24.05.2007 14:36:25]: end_QOS_statistics

[24.05.2007 14:36:25]: Created receiver for "audio/X-ASF-PF" subsession
(client ports 1048-1049)
[24.05.2007 14:36:25]: Ignoring "application/X-WMS-RTX" subsession,
because we've asked to receive a single audio session only
[24.05.2007 14:36:25]: Ignoring "video/X-ASF-PF" subsession, because
we've asked to receive a single audio session only
[24.05.2007 14:36:25]: Setup "audio/X-ASF-PF" subsession (client ports
1048-1049)
[24.05.2007 14:36:25]: Outputting data from the "audio/X-ASF-PF"
subsession to 'stdout'
[24.05.2007 14:36:25]: Started playing session
[24.05.2007 14:36:25]: Receiving streamed data (for up to 25.000000
seconds)...
[24.05.2007 14:36:25]: Data packets have begun arriving [1180017361008]
[24.05.2007 14:36:25]: begin_QOS_statistics
[24.05.2007 14:36:25]: server_availability      100
[24.05.2007 14:36:25]: stream_availability      100
[24.05.2007 14:36:25]: subsession       audio/X-ASF-PF
[24.05.2007 14:36:25]: num_packets_received     136
[24.05.2007 14:36:25]: num_packets_lost 0
[24.05.2007 14:36:25]: sdur_sec 25.034147
[24.05.2007 14:36:25]: trans_kB_tot     409.088000
[24.05.2007 14:36:25]: measurement_sampling_interval_ms 100
[24.05.2007 14:36:25]: kbps_min 0.000000
[24.05.2007 14:36:25]: kbps_avg 130.729599
[24.05.2007 14:36:25]: kbps_max 1443.854439
[24.05.2007 14:36:25]: loss_percent_min 0.000000
[24.05.2007 14:36:25]: loss_percent_avg 0.000000
[24.05.2007 14:36:25]: loss_percent_max 0.000000
[24.05.2007 14:36:25]: jit_ms   0.252000
[24.05.2007 14:36:25]: ipg_ms_min       0.155000
[24.05.2007 14:36:25]: ipg_ms_avg       177.394507
[24.05.2007 14:36:25]: ipg_ms_max       1123.697000
[24.05.2007 14:36:25]: end_QOS_statistics

Thanx for your help in advance,
David Wendel.