Galène videoconferencing server discussion list archives
 help / color / mirror / Atom feed
From: Juliusz Chroboczek <>
To: Alexandre IOOSS <>
Subject: [Galene]  Re: Building a streaming gateway for Galène
Date: Tue, 06 Apr 2021 14:57:47 +0200	[thread overview]
Message-ID: <> (raw)
In-Reply-To: <>

> For the past two weeks I have been working on streaming from a
> broadcasting software such as OBS-Studio (that uses FFMpeg) to Galène.

This would be a great addition!  We have quite a few users that use OBS,
and, as you mention, going through the v4l virtual camera has some

> 0. Using OBS Virtual v4l2 camera, but it is not portable and has audio
> sync issues.
> 1. Streaming to a gateway that will initiate the WebRTC session with Galène.
> 2. Implement WebRTC support in OBS-Studio as an output plugin.

I would tend to agree, (1) is probably the best solution, since it avoids
bloating either Galène or OBS.

> Last week I tried to implement a gateway using GStreamer webrtcbin
> plugin, <>. Although I am able
> to stream to Galène, I observe video drops. I am circumventing the issue
> by forcing the VP8 encoder to insert a keyframe every 5 frames, but that
> seems a terrible hack.

I'll have a look at your code as soon as I have some time.  In the
meantime, there are three things that you need to do:

1. send periodic RTCP Sender Reports with accurate NTP times;
2. react to RTCP PLI packets by inserting a keyframe;
3. react to RTCP NACK packets by resending the packets listed in the NACK.

(1) is essential for proper lipsynch.  (2) is what allows a stream to
recover after a catastrophic loss event.  (3) is what allows a stream to
recover rapidly after moderate amounts of loss.

> Right now [...] I don't know if I should...

I'll have a look, think it over, then get back to you.

-- Juliusz

  reply	other threads:[~2021-04-06 12:57 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-04-06 11:05 [Galene] " Alexandre IOOSS
2021-04-06 12:57 ` Juliusz Chroboczek [this message]
2021-04-06 16:10   ` [Galene] webrtc security cameras? Dave Taht
2021-04-06 17:07     ` [Galene] " Juliusz Chroboczek
2021-04-06 17:44   ` [Galene] Re: Building a streaming gateway for Galène Alexandre IOOSS
2021-04-06 23:19     ` Juliusz Chroboczek
2021-04-07 20:40       ` Alexandre IOOSS
2021-04-07 22:01         ` Juliusz Chroboczek
2021-04-07 22:05           ` Juliusz Chroboczek
2021-04-09 13:42             ` Alexandre IOOSS
2021-04-09 13:55               ` Juliusz Chroboczek
2021-04-09 14:17               ` Juliusz Chroboczek

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:

  List information:

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \ \ \ \ \
    --subject='[Galene]  Re: Building a streaming gateway for Galène' \

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox