rtpsession: NACKs are not being sent

[David Grinberg]

Setting profiles and payload map didn’t help :( 
But I’ve found out that GstRTPRetransmissionRequest does not contain SSRC. For now a trivial fix is to manually set it inside some probe, but it would be nice to know why that happens, my guess is that it is rtpssrcdemux (which i dont use) who sets ssrc

> 19 авг. 2022 г., в 00:28, Olivier Crête <olivier.crete at collabora.com> написал(а):
> 
> Hi,
> 
> It seems like you are completely right that it's not used.
> 
> Your code also seems to be missing the "payload-type-map" property on
> the rtxrtpreceive element, but that shouldn't prevent the requests from
> being sent.
> 
> I think you also need to set the rtp-profile property on rtpsession to
> avfp or savpf.
> 
> Olivier
> 
>> On Thu, 2022-08-18 at 23:43 +0400, David Grinberg via gstreamer-devel
>> wrote:
>> Hi, I’ve already asked my question here -
>>  https://gitlab.freedesktop.org/gstreamer/gstreamer/-/issues/1386
>> 
>> Suggestion of adding rtcp-fb-nack=(boolean)true didn’t work, also
>> there isn’t any reference to rtcp-fb-nack in rtpsession code (though
>> it is used by webrtcbin). 
>> The problem is that find_source fails and I don’t really know why
> 
> -- 
> Olivier Crête
> olivier.crete at collabora.com