Re: [Cellar] Adding private elements to Matroska

Moritz Bunkus <> Fri, 13 April 2018 19:56 UTC

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From: Moritz Bunkus <>
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Date: Fri, 13 Apr 2018 21:56:24 +0200
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Subject: Re: [Cellar] Adding private elements to Matroska
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> In general, I'm opposed to private elements in Matroska. If, for some
> reason, attachments and tags aren't feasible, I could concede to adding a
> new global master element that is comprised of two child binary elements:
> one acting as an identifier, and one acting as a payload. That way any
> arbitrary private info could be identified stored anywhere in the
> file. But I'd prefer to avoid that, if possible.

That would be the equivalent of a tagging system with arbitrary key/value
pairs, albeit without the existing targeting facilities (the
\Segment\Tags\Tag\Targets element). I don't like that approach much,
e.g. because it would mean duplication of data if the same private data
should be applied to multiple tracks.

Additionally the scope of such elements wouldn't be entirely clear: would
there be a difference between that element being a direct child of a
\Segement\Tracks\TrackEntry and being a child of
e.g. \Segment\Tracks\TrackEntry\Audio?

I'd rather see the use of the existing attachments & tags systems for this.

Kind regards,