[Freeswitch-dev] question about CNG on late packages

[Bing LI]

In my experience suppress_cng did work but only prevented sending CNG
packet.
freeswitch would ignore the late packets because it thought the cng packet
had been sent out. it makes a hole in the seq number in B-leg.

So later I modified the switch_rtp.c to change this mechanism.



On Tue, Feb 5, 2013 at 11:32 AM, Xijing Dai <dxj19831029 at gmail.com> wrote:

> I see.
>
>
> I did set it suppress_cng=true, and it did not help. No difference at all.
>
> This happens inside LAN.
>
> When talking about the jitter buffer, we want to enable it on client, and
> disable it inside freeswitch.
> Therefore, in this case, should freeswitch do nothing?
>
>
> Cheers
>
>
>
>
> On Tue, Feb 5, 2013 at 11:35 PM, Anthony Minessale <
> anthony.minessale at gmail.com> wrote:
>
>> Don't negotiate CNG in the SDP and it won't use it or disable it with
>> suppress_cng=true in your channel or global vars.
>>
>>
>>
>> On Tue, Feb 5, 2013 at 4:32 AM, Steven Ayre <steveayre at gmail.com> wrote:
>>
>>> Because if a RTP packet is due and hasn't arrived yet you need something
>>> to play. Audio isn't like TCP where you dropped packets can be
>>> retransmitted, if it hasn't arrived by the time you want to play it it's
>>> too late and you have to play silence to handle it.
>>>
>>> Your audio problems are more likely due to packet loss or jitter which
>>> is why the RTP packet is overdue, not the CNG itself.
>>>
>>> It jitter's the problem enabling the jitterbuffer might help (at the
>>> expense of increased lag). If loss is the problem there's no way to handle
>>> that except as silence for the missing interval, you need to fix whatever
>>> is causing the loss.
>>>
>>> -Steve
>>>
>>>
>>> On 5 February 2013 10:23, Xijing Dai <dxj19831029 at gmail.com> wrote:
>>>
>>>> Hey all,
>>>>
>>>>
>>>> Inside code
>>>>
>>>> switch_rtp.c file:
>>>>
>>>>    static int rtp_common_read(switch_rtp_t *rtp_session,
>>>> switch_payload_t *payload_type, switch_frame_flag_t *flags,
>>>> switch_io_flag_t io_flags)
>>>>                  ................
>>>>                  if (check || (bytes && !switch_test_flag(rtp_session,
>>>> SWITCH_RTP_FLAG_USE_TIMER))) {
>>>> if (!bytes && switch_test_flag(rtp_session, SWITCH_RTP_FLAG_USE_TIMER))
>>>> { /* We're late! We're Late! */
>>>>  if (!switch_test_flag(rtp_session, SWITCH_RTP_FLAG_NOBLOCK) && status
>>>> == SWITCH_STATUS_BREAK) {
>>>> switch_cond_next();
>>>>  continue;
>>>> }
>>>>
>>>> return_cng_frame();  <------- this lane to return cng frame if late.
>>>>  }
>>>> }
>>>>
>>>>
>>>> Could someone explain why we want to return cng frame when package is
>>>> late? this is caused for me to hear very bad noise audio.
>>>>
>>>> Can I disable return CNG frame?
>>>>
>>>>
>>>> Cheers
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> _________________________________________________________________________
>>>> Professional FreeSWITCH Consulting Services:
>>>> consulting at freeswitch.org
>>>> http://www.freeswitchsolutions.com
>>>>
>>>> 
>>>> 
>>>>
>>>> Official FreeSWITCH Sites
>>>> http://www.freeswitch.org
>>>> http://wiki.freeswitch.org
>>>> http://www.cluecon.com
>>>>
>>>> FreeSWITCH-dev mailing list
>>>> FreeSWITCH-dev at lists.freeswitch.org
>>>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-dev
>>>> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-dev
>>>> http://www.freeswitch.org
>>>>
>>>>
>>>
>>> _________________________________________________________________________
>>> Professional FreeSWITCH Consulting Services:
>>> consulting at freeswitch.org
>>> http://www.freeswitchsolutions.com
>>>
>>> 
>>> 
>>>
>>> Official FreeSWITCH Sites
>>> http://www.freeswitch.org
>>> http://wiki.freeswitch.org
>>> http://www.cluecon.com
>>>
>>> FreeSWITCH-dev mailing list
>>> FreeSWITCH-dev at lists.freeswitch.org
>>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-dev
>>> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-dev
>>> http://www.freeswitch.org
>>>
>>>
>>
>>
>> --
>> Anthony Minessale II
>>
>> FreeSWITCH http://www.freeswitch.org/
>> ClueCon http://www.cluecon.com/
>> Twitter: http://twitter.com/FreeSWITCH_wire
>>
>> AIM: anthm
>> MSN:anthony_minessale at hotmail.com
>> GTALK/JABBER/PAYPAL:anthony.minessale at gmail.com
>> IRC: irc.freenode.net #freeswitch
>>
>> FreeSWITCH Developer Conference
>> sip:888 at conference.freeswitch.org
>> googletalk:conf+888 at conference.freeswitch.org
>> pstn:+19193869900
>>
>> _________________________________________________________________________
>> Professional FreeSWITCH Consulting Services:
>> consulting at freeswitch.org
>> http://www.freeswitchsolutions.com
>>
>> 
>> 
>>
>> Official FreeSWITCH Sites
>> http://www.freeswitch.org
>> http://wiki.freeswitch.org
>> http://www.cluecon.com
>>
>> FreeSWITCH-dev mailing list
>> FreeSWITCH-dev at lists.freeswitch.org
>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-dev
>> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-dev
>> http://www.freeswitch.org
>>
>>
>
> _________________________________________________________________________
> Professional FreeSWITCH Consulting Services:
> consulting at freeswitch.org
> http://www.freeswitchsolutions.com
>
> 
> 
>
> Official FreeSWITCH Sites
> http://www.freeswitch.org
> http://wiki.freeswitch.org
> http://www.cluecon.com
>
> FreeSWITCH-dev mailing list
> FreeSWITCH-dev at lists.freeswitch.org
> http://lists.freeswitch.org/mailman/listinfo/freeswitch-dev
> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-dev
> http://www.freeswitch.org
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.freeswitch.org/pipermail/freeswitch-dev/attachments/20130205/bf32ec6e/attachment-0001.html