Re: [Linphone-developers] ortp: processing incoming stream

[Simon Morlat]

Hi Petr,

Your application should increment the timestamp using its theoritical
value (ex: 10 ms if your application is supposed to wake up and do
processing every 10 ms), no matter if it is a bit late compared to real
time or not.
The important is only that on the long term, the timestamp and the time
elapsed are equivalent (no drift).

Simon

Le vendredi 20 novembre 2009 à 14:43 +0100, Petr Kuba a écrit :
> Hello,
> 
> I'm experiencing the following problem:
> 
> Since the timer we use for calling rtp_session_recvm_with_ts() is not 
> 100% precise (mainly in windows) it happens quite often that the time 
> between two calls of rtp_session_recvm_with_ts() is (a little bit) 
> longer that 20ms. Then it is quite often that there are already two 
> packets older than current timestamp in the ortp queue.
> 
> However, rtp_session_recvm_with_ts() calls rtp_getq() which returns only 
> the last packet and discards all older packets. I believe that this is 
> not good idea when we are only few ms late.
> 
> In my case it would be better to call rtp_getq_permissive() instead of 
> rtp_getq() not to miss any packets.
> 
> What do you think? Do I miss any important idea of this algorithm? What 
> is the reason for discarding a packet that we wouldn't discard e.g. just 
> 1ms earlier?
> 
> Thanks,
> Petr
> 
>