IETF Logo Mail Archive

Re: [Cellar] Mapping of MOV clean aperture values to Matroska

Steve Lhomme <slhomme@matroska.org> Mon, 03 December 2018 07:50 UTC

Return-Path: <slhomme@matroska.org>
X-Original-To: cellar@ietfa.amsl.com
Delivered-To: cellar@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 60B64128D68 for <cellar@ietfa.amsl.com>; Sun, 2 Dec 2018 23:50:28 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -3.359
X-Spam-Level:
X-Spam-Status: No, score=-3.359 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIMWL_WL_MED=-1.459, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, RCVD_IN_DNSWL_NONE=-0.0001] autolearn=ham autolearn_force=no
Authentication-Results: ietfa.amsl.com (amavisd-new); dkim=pass (2048-bit key) header.d=matroska-org.20150623.gappssmtp.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 kQGZv5n-0bnM for <cellar@ietfa.amsl.com>; Sun, 2 Dec 2018 23:50:26 -0800 (PST)
Received: from mail-pl1-x630.google.com (mail-pl1-x630.google.com [IPv6:2607:f8b0:4864:20::630]) (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 286BB124C04 for <cellar@ietf.org>; Sun, 2 Dec 2018 23:50:26 -0800 (PST)
Received: by mail-pl1-x630.google.com with SMTP id u18so6028206plq.7 for <cellar@ietf.org>; Sun, 02 Dec 2018 23:50:26 -0800 (PST)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=matroska-org.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=KbGe9IKzYQ+mY8VbV8cJP8L4m4ExibJstL/0jz2lwmY=; b=gYsoTny75zzuPhLfP64Ncd1XUV+oYq1LqYgsPIhuGGzMZ/FkRBNdEYe4D7dqXqXfNX twe9b4lXSvUe4G7JJbp13TXnlCSy5ltycnX2MKrU1gO/ErkKQbpr0SCTGP2MYOr98tTn Vvhf2WNl+5HWAgDC4PwqzRWX705TZnulzX1xVObBpnNd4pVuBz7nwXB12n7sE7FEVg81 XkFmHc1cJgzsjs6FSz6Xo6wS/rUZHK6ofwgzXOvbxDM/m8PSogBLmLEcXcSK+olGnmkk fnp6XBekzWHYpBFuXwoHgJbBdzMaS8SUnIPR4IxbGKEGV3Umsz6JHOf0M3mKlfpgrmE9 nU/Q==
X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=KbGe9IKzYQ+mY8VbV8cJP8L4m4ExibJstL/0jz2lwmY=; b=otcghWhDhlYLP8JXQLVclcoCvaZy5qvXoBHK377B1o9NPuXir/Vqn/cA1Jb62w5/af cJ7HhTjvsB8L4GsKMzeeqZ+mQ2Suce5hHtsh9RrB3DlJifSDTQ7dcHQz0A3A9WeYR8k4 nZBEP8R46Y1g1Q/5W1H32yABv8NAqJXRlxfzpiKiwIhmjpw/gQx6QMJbcyj9HK4iaXjE bIhb7pLrwnihw5ndbvzzopGqePRvt261m8NhpV4OUKHshZYRGsDMAtC5aLe7KjernYKh o2TtAdXDBcxYsC/dDCoSfvtGqvOoM+PKVp5svsxmOKNl4r3oiwhz+2rFP4qaUkoyAm2N f7sg==
X-Gm-Message-State: AA+aEWZsVGiBKjqQ2c8FF2PhzU5RjRE4MzBhyaNAH6c+9wgXjMPQ66OF zgZ5XYP38IkmqjZwdRFqBIjzM0rzafcevnQfMnURXg==
X-Google-Smtp-Source: AFSGD/VuVVfhnoTD9RxX7kd4ZU79ItX+N5vOUO1YjNu2kCF2YdnSuQFnpzyBoEbJv1Ib16fI0RMl5DhPGnXnepVRelI=
X-Received: by 2002:a17:902:9047:: with SMTP id w7mr15067509plz.270.1543823425701; Sun, 02 Dec 2018 23:50:25 -0800 (PST)
MIME-Version: 1.0
References: <CAO7v-1Qci+eGHBbQYuHYn-fSb+WA+ac-=Z89zkcdcYpQaKGQEw@mail.gmail.com> <353D4CFD-370C-4509-B7BE-3D572EC2DEFB@dericed.com> <CAO7v-1RqTcC4ty0O-Qk99g_FoRGhyNb_uTDcj6JxcAbM34sscg@mail.gmail.com> <CAOXsMFL7hv=iA7WTnv_FHJSmcOzHspXfF57Xi+PY7BJR5A+nUw@mail.gmail.com> <CAO7v-1QEuW5oQBd5PBq2cD8ZPLU9kjd1L9c8v=KJ2TKMNcJyiQ@mail.gmail.com> <CAOXsMFJVLusiRZpFNCAwkZCA6CjnbYvx06ARopdCPswqBCoVpA@mail.gmail.com>
In-Reply-To: <CAOXsMFJVLusiRZpFNCAwkZCA6CjnbYvx06ARopdCPswqBCoVpA@mail.gmail.com>
From: Steve Lhomme <slhomme@matroska.org>
Date: Mon, 3 Dec 2018 08:50:15 +0100
Message-ID: <CAOXsMFJek_HrnhY=Hz_04dV0udCHHQvT5e4LR0AXo6JMXMmeHA@mail.gmail.com>
To: Kieran O Leary <kieran.o.leary@gmail.com>
Cc: Codec Encoding for LossLess Archiving and Realtime transmission <cellar@ietf.org>
Content-Type: text/plain; charset="UTF-8"
Archived-At: <https://mailarchive.ietf.org/arch/msg/cellar/kjAPiZGxhHqGG5xsFMmdd3Z5-y4>
Subject: Re: [Cellar] Mapping of MOV clean aperture values to Matroska
X-BeenThere: cellar@ietf.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Codec Encoding for LossLess Archiving and Realtime transmission <cellar.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/cellar>, <mailto:cellar-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/cellar/>
List-Post: <mailto:cellar@ietf.org>
List-Help: <mailto:cellar-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/cellar>, <mailto:cellar-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 03 Dec 2018 07:50:28 -0000

> >> In Matroska we assume that we override what the codec says.
> >> But I don't think that's how it's handled in ffmpeg. Also there's the
> >> question of what these values apply to: on the decoded surface, which
> >> may include padding on the right/bottom or the area that's supposed to
> >> be visible. In Matroska the "PixelWidth/PixelHeight" correspond to the
> >> visible area, on which we apply extra cropping. (this is currently not
> >> written anywhere).
> >>
> >> As for the MOV atom, is there are spec somewhere ? Or is it clear that
> >> it's some cropping ?
> >
> >
> > I think this is as good of a spec that is freely available - the 'clap section' https://developer.apple.com/library/archive/documentation/QuickTime/QTFF/QTFFChap3/qtff3.html#//apple_ref/doc/uid/TP40000939-CH205-125850
>
> OK, so we should support it in VLC (which we don't) and that seems to
> map more or less to Matroska values.

I see you submitted a feature request already, excellent
https://trac.videolan.org/vlc/ticket/21179

v2.1.2.p1 | Report a Bug | By Email