From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: mail.toke.dk; spf=pass (mailfrom) smtp.mailfrom=irif.fr (client-ip=2001:660:3301:8000::1:2; helo=korolev.univ-paris7.fr; envelope-from=jch@irif.fr; receiver=) Received: from korolev.univ-paris7.fr (korolev.univ-paris7.fr [IPv6:2001:660:3301:8000::1:2]) by mail.toke.dk (Postfix) with ESMTPS id 1A1708291EF for ; Fri, 9 Apr 2021 15:55:39 +0200 (CEST) Received: from potemkin.univ-paris7.fr (potemkin.univ-paris7.fr [IPv6:2001:660:3301:8000::1:1]) by korolev.univ-paris7.fr (8.14.4/8.14.4/relay1/82085) with ESMTP id 139DtZVb028337 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=NO); Fri, 9 Apr 2021 15:55:35 +0200 Received: from mailhub.math.univ-paris-diderot.fr (mailhub.math.univ-paris-diderot.fr [81.194.30.253]) by potemkin.univ-paris7.fr (8.14.4/8.14.4/relay2/82085) with ESMTP id 139DtZCW012324; Fri, 9 Apr 2021 15:55:35 +0200 Received: from mailhub.math.univ-paris-diderot.fr (localhost [127.0.0.1]) by mailhub.math.univ-paris-diderot.fr (Postfix) with ESMTP id 3A4FCFCABE; Fri, 9 Apr 2021 15:55:35 +0200 (CEST) X-Virus-Scanned: amavisd-new at math.univ-paris-diderot.fr Received: from mailhub.math.univ-paris-diderot.fr ([127.0.0.1]) by mailhub.math.univ-paris-diderot.fr (mailhub.math.univ-paris-diderot.fr [127.0.0.1]) (amavisd-new, port 10023) with ESMTP id MdsLiXD6lCPJ; Fri, 9 Apr 2021 15:55:33 +0200 (CEST) Received: from pirx.irif.fr (unknown [78.194.40.74]) (Authenticated sender: jch) by mailhub.math.univ-paris-diderot.fr (Postfix) with ESMTPSA id 5A5A6FCABC; Fri, 9 Apr 2021 15:55:33 +0200 (CEST) Date: Fri, 09 Apr 2021 15:55:33 +0200 Message-ID: <87k0pbo94a.wl-jch@irif.fr> From: Juliusz Chroboczek To: Alexandre IOOSS In-Reply-To: <802366a1-df1b-3b4c-4c0d-b49c0dde9210@crans.org> References: <228e92c1-d1f7-bc6d-4f44-c9cfd28f0096@crans.org> <87zgybsh84.wl-jch@irif.fr> <76e5b62b-ee5b-3117-ea04-368fab0e659b@crans.org> <877dlfrofb.wl-jch@irif.fr> <87wntdn49u.wl-jch@irif.fr> <87tuohn42a.wl-jch@irif.fr> <802366a1-df1b-3b4c-4c0d-b49c0dde9210@crans.org> User-Agent: Wanderlust/2.15.9 (Almost Unreal) Emacs/27.1 Mule/6.0 MIME-Version: 1.0 (generated by SEMI-EPG 1.14.7 - "Harue") Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (korolev.univ-paris7.fr [IPv6:2001:660:3301:8000::1:2]); Fri, 09 Apr 2021 15:55:35 +0200 (CEST) X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.7 (potemkin.univ-paris7.fr [194.254.61.141]); Fri, 09 Apr 2021 15:55:35 +0200 (CEST) X-Miltered: at korolev with ID 60705CD7.000 by Joe's j-chkmail (http : // j-chkmail dot ensmp dot fr)! X-Miltered: at potemkin with ID 60705CD7.000 by Joe's j-chkmail (http : // j-chkmail dot ensmp dot fr)! X-j-chkmail-Enveloppe: 60705CD7.000 from potemkin.univ-paris7.fr/potemkin.univ-paris7.fr/null/potemkin.univ-paris7.fr/ X-j-chkmail-Enveloppe: 60705CD7.000 from mailhub.math.univ-paris-diderot.fr/mailhub.math.univ-paris-diderot.fr/null/mailhub.math.univ-paris-diderot.fr/ X-j-chkmail-Score: MSGID : 60705CD7.000 on korolev.univ-paris7.fr : j-chkmail score : . : R=. U=. O=. B=0.000 -> S=0.000 X-j-chkmail-Score: MSGID : 60705CD7.000 on potemkin.univ-paris7.fr : j-chkmail score : . : R=. U=. O=. B=0.000 -> S=0.000 X-j-chkmail-Status: Ham X-j-chkmail-Status: Ham Message-ID-Hash: NH6YSCB35IWAKUOCMKNMTVDTJARIEBB7 X-Message-ID-Hash: NH6YSCB35IWAKUOCMKNMTVDTJARIEBB7 X-MailFrom: jch@irif.fr X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: galene@lists.galene.org X-Mailman-Version: 3.3.4 Precedence: list Subject: [Galene] Re: Building a streaming gateway for =?iso-8859-1?q?Gal=E8ne?= List-Id: =?utf-8?q?Gal=C3=A8ne_videoconferencing_server_discussion_list?= Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: > 1. PLI are working fine, and I can confirm that Gal=E8ne manages to ask > for keyframes. Excellent. This means you can reduce the rate of periodic keyframes to something pretty minimal (like one per minute), and expect the stream to recover within a second or so after a packet loss, even if NACK recovery is broken. > 2. NACK are received but ignored because my GStreamer webrtcbin element > doesn't have "RTX" enabled. Ah... right. Gal=E8ne doesn't use a separate RTX track for retransmissions, it expects the client to honour retransmissions on the main audio track. Let me explain. There are two ways you can do retransmissions in WebRTC: by simply resending the original packet, or by using an auxiliary "RTX" track that is only used for retransmissions. Since Pion v2 didn't support RTX tracks, Gal=E8ne takes the former approach -- this makes it slightly more difficult to properly account for lost packets, but it's much simpler. Browsers support both, and are happy to retransmit packets over the main track when there is no dedicated RTX track. Now that Gal=E8ne uses Pion v3, it should be possible to add support for dedicated RTX tracks to it. Don't hold your breath, though, I've got a few deadlines looming and am very busy with other stuff right now. Sorry. -- Juliusz