[SR-Users] Change in RTP Payload time on the fly

[Vikram Ragukumar]

Ovidiu,

> If you have a codec that has silence suppression enabled, then you may
> get all kind of arbitrary lengths for packets (as silence suppression
> may kick in at any time).
> Disable silence suppression on both ends and retest.  If you are still
> seeing variable length packets then there might be a problem.

Thank you for your reply. That is a good point that you raise. However,
we did ensure that Silence suppression was disabled in all our tests.

Upon further investigation we have found that occasionally there is a
"timeout" (corresponding to the instances when proxy sends a packet with
size less than what was requested of the resizer), i.e. the following
check in rtp_resizer.c (rtpproxy v1.2.1)
fails (line num 230)

"if(this->nsamples_total < this->output_nsamples &&
   ts_less(ref_ts, this->queue.first->ts + this->output_nsamples + 160))"

The condition to the right of the logical 'and (&&)' seems to fail. We
notice that this failure happens immediately after the list of previously
enqueued packets has been emptied.

Is this caused by network jitter ? Also, why is there a 160 that is
added in the above check.. would increasing that cause fewer timeouts ?

Thanks and Regards,
Vikram