Hi Ravi, Not sure how Wireshark do the calculation, however, the standard reference of calculating jitter is RFC 3550 A.8. And mean, max, min, std dev of jitter are calculated as in common statistical definition. That's the calculation method used in pjmedia rtcp. Regards, nanang 2008/6/16 Ravi Inder Singh <raviinder at gmail.com>: > Hi Nanang, > Thanks alot. > This seems to be different method from which wireshark is using , > wireshark uses (sum of all deltas) / no of packets. > > In this file aaa.cap attached , in Statitics ---> RTP--> show all streams, > it shows means Jitter 18.09. > Your method defined above doesn't give same values . > > And in another file mean_calc.pcap ,from (172.26.1.101 --> 172.26.1.104 ) it > calculates mean with different method.(Mean value is 1.28 ). I dont have any > idea over that ? > > Does this wireshark uses some different calculation methodology for > calculating mean for different no of packets or I am missing something ? > > Coz all are using different method for calculation so i am confused over it > . > > > > Thanks & Regards, > Ravi > > On Mon, Jun 16, 2008 at 1:43 PM, Nanang Izzuddin <nanang at pjsip.org> wrote: >> >> Hi Ravi, >> >> Yes, that is mean jitter, but it seems you are using 0.8.0, no >> standard deviation jitter calculation in that version. If you work >> with the latest SVN source, you will get both calculations: mean >> jitter & standard deviation, even some report blocks of RTCP XR are >> already implemented (stats summary is one of them). >> >> Cheers, >> nanang >> >> >> 2008/6/16 Ravi Inder Singh <raviinder at gmail.com>: >> > Hi Benny, >> > I need to calculate Mean Jitter & Deviation Jitter , as per RFC 3611 >> > section 4.6 Stats Summary Block >> > Is this calculation below is mean jitter >> > sess->avg_jitter = >> > (jitter + sess->avg_jitter * sess->stat.rx.jitter.count) / >> > (sess->stat.rx.jitter.count + 1); >> > >> > And also Standard deviation jitter for the same. >> > >> > >> > -- >> > Thanks & Regards, >> > Ravi Inder Singh >> > _______________________________________________ >> > Visit our blog: http://blog.pjsip.org >> > >> > pjsip mailing list >> > pjsip at lists.pjsip.org >> > http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org >> > >> > >> >> _______________________________________________ >> Visit our blog: http://blog.pjsip.org >> >> pjsip mailing list >> pjsip at lists.pjsip.org >> http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org > > > > -- > Thanks & Regards, > Ravi Inder Singh > _______________________________________________ > Visit our blog: http://blog.pjsip.org > > pjsip mailing list > pjsip at lists.pjsip.org > http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org > >
