Re: [Cellar] Update specification language: CodecPrivate element MUST be set for H264 in Matroska

Moritz Bunkus <mo@bunkus.online> Sun, 27 December 2020 16:35 UTC

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From: Moritz Bunkus <mo@bunkus.online>
To: Jerome Martinez <jerome@mediaarea.net>
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Date: Sun, 27 Dec 2020 17:35:03 +0100
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Subject: Re: [Cellar] Update specification language: CodecPrivate element MUST be set for H264 in Matroska
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Hey,

while it's true that _from the EBML PoV_ the CodecPrivate element isn't
mandatory, it still must be present for certain codecs in order for them to
be decodable. So yes, their request is that we say something like: "for
Codec == V_ABC/DEF/GHI the CodecPrivate element MUST be present. It MUST
contain data according to ReferenceToSomeOtherStandard."

Not only that the content MUST contain data following certain format, but
also that the element MUST be present.

Kind regards,
mosu