From lydia@airtime.com Fri Jun 4 13:13:03 2021 Return-Path: X-Original-To: rtcweb@ietfa.amsl.com Delivered-To: rtcweb@ietfa.amsl.com Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 684B33A1F69 for ; Fri, 4 Jun 2021 13:13:03 -0700 (PDT) X-Virus-Scanned: amavisd-new at amsl.com X-Spam-Flag: NO X-Spam-Score: -0.48 X-Spam-Level: X-Spam-Status: No, score=-0.48 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, HTML_IMAGE_ONLY_24=1.618, HTML_MESSAGE=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=no autolearn_force=no Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (1024-bit key) header.d=airtime.com Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id bKMCg7HtjC1R for ; Fri, 4 Jun 2021 13:12:58 -0700 (PDT) Received: from mail-ed1-x530.google.com (mail-ed1-x530.google.com [IPv6:2a00:1450:4864:20::530]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 999293A1F9F for ; Fri, 4 Jun 2021 13:12:58 -0700 (PDT) Received: by mail-ed1-x530.google.com with SMTP id ba2so10785305edb.2 for ; Fri, 04 Jun 2021 13:12:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=airtime.com; s=airtime; h=mime-version:from:date:message-id:subject:to; bh=kN0toB0Ip8Hw0xdhkAG6ZjQIcwzKvnPoB98pDRd8OfI=; b=Qm/T821o9pq7Nw2FCKIivOPdtMtJ78gq5hII39avd7ESQhfdQn/DOln2/9n6kstKV1 2jENxl/SHxinoW2DLLtqa/ri0Ov88qPBfYU34Dz4Lv4MLliDoYng8d6zxoxMDAeGEztk ec4FdDzIrzlFq4RXypIWYV5tIDZFktd99OsPg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:from:date:message-id:subject:to; bh=kN0toB0Ip8Hw0xdhkAG6ZjQIcwzKvnPoB98pDRd8OfI=; b=LYYlgxOR3p6qUVMEdbZFY2hLVk2APvrzmEepAFOdgy9J6uHpNbKXWxRvjC6xbqIYcN QNmNxMfLig9e5pWTbklngUItKHzv0LjuS37e6rUQ1deaiSpZ7frK5VKs1h+zeuN9Bm41 3/UQ7xi1XSNzDeGThXtVHmFb+ASf/vJugXg0hX277LKzQhQUxVDXQCA++wor4U0H7ANf BUMvi3BNiI+DTkQJM0oAA+NTHkd7+xBM+H12+KhIY3c1OppQsfqOit9flHMkfz1/TMgg VMlZo8Dj7OB7+uUG11v47TqYsK4yfopv8XsQ+TLU7AjPCs0FvEss3J5QnJe4guFDw6eD 9CTA== X-Gm-Message-State: AOAM530kXG/JYjQ/FlQ35fqiUZNVZJYSMxA7a5yBDUUzUzgFOIOQlvhn eYhDwx8RkZehoG+cj1UAmq+oIE3ZjfSKfPeZPOixxVHO57/Xzw== X-Google-Smtp-Source: ABdhPJx9LUDFwabsgmu3AF2jt8vEgHl1vejd7KUfg4nJ9H68ArA9XFAAvrciqss3g69KETL8dO/YOZjZDsSONsbZTFM= X-Received: by 2002:a05:6402:1644:: with SMTP id s4mr6621103edx.190.1622837571758; Fri, 04 Jun 2021 13:12:51 -0700 (PDT) MIME-Version: 1.0 From: Lydia Sun Date: Fri, 4 Jun 2021 13:12:41 -0700 Message-ID: To: rtcweb@ietf.org Content-Type: multipart/alternative; boundary="000000000000fe47e905c3f6509a" Archived-At: X-Mailman-Approved-At: Tue, 08 Jun 2021 06:43:41 -0700 Subject: [rtcweb] A/V sync after audio interruption on iOS X-BeenThere: rtcweb@ietf.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Real-Time Communication in WEB-browsers working group list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 07 Jun 2021 17:34:01 -0000 --000000000000fe47e905c3f6509a Content-Type: text/plain; charset="UTF-8" Hi all, I work on the media team at Airtime, a platform for live video chat and co-watching content. Our team has come across an audio/video sync issue on iOS -- we are wondering if anyone else has seen this or has some insight into the problem: 1. A publisher is publishing audio and video. 2. The publisher receives an audio interrupt, such as a phone call or a timer going off. 3. The interrupt ends with the phone call rejected or the timer stopped. 4. After this, the subscriber sees that the publisher's audio and video are out of sync. Our application does not use CallKit, so that for the duration of the interrupt no audio samples are captured. Has anyone observed something similar before? If interested, I am happy to share some other findings that we have collected regarding the behavior of RTP timestamps and RTCP sender reports surrounding the audio interrupt -- I am leaving it out here to avoid adding a wall of text. Best, Lydia -- Lydia Sun Software Engineer, Media lydia@airtime.com airtime.com --000000000000fe47e905c3f6509a Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi all,

I work on the media team at Airt= ime, a platform for live video chat and co-watching content.
O= ur team has come across an audio/video sync issue on iOS -- we are wonderin= g if anyone else has seen this or has some insight into the problem:
<= div>
  1. A publisher is publishing audio and video.
  2. The publishe= r receives an audio interrupt, such as a phone call or a timer going off.
  3. The interrupt ends with the phone call rejected or the timer stopped= .
  4. After this, the subscriber sees that the publisher's audio an= d video are out of sync.
Our application doe= s not use CallKit, so that for the duration of the interrupt no audio sampl= es are captured.

Has anyone observed something= similar before? If interested, I am happy to share some other findings tha= t we have collected regarding the behavior of RTP timestamps and RTCP sende= r reports surrounding the audio interrupt -- I am leaving it out here to av= oid adding a wall of text.

Best,
Lydia--
Lydia Sun
 Software Engineer, Media


lydia@airtime.com
 airtime.com
--000000000000fe47e905c3f6509a-- From nobody Mon Jun 21 16:41:55 2021 Return-Path: X-Original-To: rtcweb@ietf.org Delivered-To: rtcweb@ietfa.amsl.com Received: from ietfa.amsl.com (localhost [IPv6:::1]) by ietfa.amsl.com (Postfix) with ESMTP id 360AC3A1EED; Mon, 21 Jun 2021 16:41:53 -0700 (PDT) MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit From: IETF Meeting Session Request Tool To: Cc: lflynn@amsl.com, rtcweb-chairs@ietf.org, rtcweb@ietf.org, superuser@gmail.com X-Test-IDTracker: no X-IETF-IDTracker: 7.32.0 Auto-Submitted: auto-generated Precedence: bulk Message-ID: <162431891314.781.9458630996368437190@ietfa.amsl.com> Date: Mon, 21 Jun 2021 16:41:53 -0700 Archived-At: Subject: [rtcweb] rtcweb - New Meeting Session Request for IETF 111 X-BeenThere: rtcweb@ietf.org X-Mailman-Version: 2.1.29 List-Id: Real-Time Communication in WEB-browsers working group list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 21 Jun 2021 23:41:53 -0000 A new meeting session request has just been submitted by Liz Flynn, on behalf of the rtcweb working group. --------------------------------------------------------- Working Group Name: Real-Time Communication in WEB-browsers Area Name: Applications and Real-Time Area Session Requester: Liz Flynn Number of Sessions: 1 Length of Session(s): 1 Hour Number of Attendees: 100 Conflicts to Avoid: Technology Overlap: mmusic dispatch dmarc emailcore People who must be present: Sean Turner Murray Kucherawy Ted Hardie Resources Requested: Special Requests: ---------------------------------------------------------