Re: [Cellar] Conversation about a NON-IANA request in Matroska

Spencer Dawkins at IETF <> Wed, 18 August 2021 21:54 UTC

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From: Spencer Dawkins at IETF <>
Date: Wed, 18 Aug 2021 16:53:35 -0500
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To: Murray Kucherawy <>
Cc: Francesca Palombini <>, Codec Encoding for LossLess Archiving and Realtime transmission <>
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Subject: Re: [Cellar] Conversation about a NON-IANA request in Matroska
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Hi, Murray,

Just following up - have you had an opportunity to think about this yet?

If you have questions, Cellar is having our monthly interim meeting next
Tuesday, and you are, of course, welcome to swing by!



On Tue, Aug 10, 2021 at 12:17 PM Spencer Dawkins at IETF <> wrote:

> Hi, Murray, the backup expert reviewer for Media Types, and our
> responsible AD,
> Cellar is working on the Matroska specification, and one issue we've
> tripped over is that Matrosks implementations have traditionally used
> unregistered MIME types such as "video/x-matroska" and file extension
> ".mkv", which have never been registered in the Media Types registry, and
> (for extra credit) use "x-dash" notation that someone is likely to ask us
> to change, if we were registering something now.
> Specifically, the media types mentioned in
> have been in use for up to 19 years, and the sense of the Github discussion
> is that actually registering them now won't have much impact on anything.
> (You should be tagged in that PR, and that's where most of the discussion
> I've seen has happened)
> And we'd prefer not to start that conversation during AD Evaluation, IETF
> Last Call, or (especially not!) during IESG Evaluation and formal IANA
> review.
> As this work moves forward in the IETF stream, we wanted to ask, is this a
> thing we should talk with you about, sooner rather than later?
> Best,
> Spencer