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<p>Thanks Matthew!<br>
</p>
On 16-03-2022 01:49, Matthew Waters via gstreamer-devel wrote:<br>
<blockquote type="cite"
cite="mid:dae6883c-6f87-03d2-acf6-695a105bd8f5@gmail.com">
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Hi,<br>
<br>
<div class="moz-cite-prefix">On 16/3/22 03:09, Michiel Konstapel
via gstreamer-devel wrote:<br>
</div>
<blockquote type="cite"
cite="mid:20084d2d-d0c9-e413-6aec-d536dd3e0cfb@aanmelder.nl">
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<p>Aha - it does appear to work if I set "bundle-policy" to
"max-bundle". At least, then I see it setting up the pt map,
and I see it creating/pushing rtx buffers. It doesn't seem to
immediately work wonders for combating packet loss, though,
but I do think it runs a little smoother.</p>
<p>So RTX doesn't work with the default bundle-policy, is that
correct?<br>
</p>
</blockquote>
<br>
Unknown. If you're talking with a browser, then you can pretty
much always use max-bundle so the other modes don't get too much
testing. The whole bundle-policy thing is also up for potential
removal at some point in the WebRTC specification.<br>
</blockquote>
<p>I figured I'd stick with default values (like bundle-policy) if I
don't understand the impact. This is purely streaming to browsers,
so I'll use max-bundle then. Should I create a ticket for the bug
impacting the default policy?<br>
</p>
<blockquote type="cite"
cite="mid:dae6883c-6f87-03d2-acf6-695a105bd8f5@gmail.com">
<blockquote type="cite"
cite="mid:20084d2d-d0c9-e413-6aec-d536dd3e0cfb@aanmelder.nl">
<blockquote type="cite"
cite="mid:1e742b3c-c7f2-6a1e-23c7-7c3be196b271@aanmelder.nl">Looks
like this is the call from
gstwebrtcbin.c:on_rtpbin_request_aux_sender, but that only
assigns stream->rtxsend AFTER the call to
_set_rtx_ptmap_from_stream. </blockquote>
</blockquote>
<br>
This was an issue that may have only been fixed in latest git.</blockquote>
<p>I'm looking at master now, but it <a
href="https://github.com/GStreamer/gst-plugins-bad/blob/master/ext/webrtc/gstwebrtcbin.c#L6117">looks
like</a> this code path is unchanged.</p>
<p>By the way - do you happen to know if nack/rtx actually works
when streaming to a browser? I figured retransmits would easily
hide 1% packet loss. I see the browser sending nacks, and I see
rtprtxsend pushing out buffers, but I see no visual improvement.
Is there any statistic I can get from the browser that shows
whether the retransmits are arriving (at all, and on time?) Would
VP8 or VP9 cope with packet loss better than H.264?<br>
</p>
<p>Cheers,<br>
Michiel<br>
</p>
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