netoptimizer / IPTV-Analyzer

Fast MPEG2 Transport Stream Analyzer, based on Netfilter kernel module
www.iptv-analyzer.org
GNU General Public License v3.0
97 stars 55 forks source link

Implementing PCR clock measurements and analysis #14

Open netoptimizer opened 10 years ago

netoptimizer commented 10 years ago

Decoding the MPEG2TS PCR clock is available in commercial solutions, the plan is to also implement this.

It should be fairly straight forward, as I once wrote a PCR patch for wireshark (that was never accepted into mainline). See: https://bugs.wireshark.org/bugzilla/show_bug.cgi?id=4338

From wirehark link:

MPEG2 Transport Stream (mp2t / RFC 2250 / ISO/IEC 13818-1): Implementing PCR clock measurements and analysis.

The PCR clock and bytes deltas values are recorded, between two PCR packets. First of all the PCR delta is converted to a human understandable time in ms. Using the byte delta we calculate the bandwidth, that the streamer intended to transmit with.

Using this together with IO-graph provides a power full tool to analyse the quality of your streamers PCR clock. Advanced use of IO-graph can also show the correlation between the PCR bandwidth and the capture time bandwidth.