Re: [Cellar] Matroska Elements to support frame side data

Tobias Rapp <t.rapp@noa-archive.com> Fri, 02 November 2018 09:31 UTC

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From: Tobias Rapp <t.rapp@noa-archive.com>
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Subject: Re: [Cellar] Matroska Elements to support frame side data
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Hi Dave,

On 01.11.2018 15:03, Dave Rice wrote:
> [...]
> 
> Here are a few use cases where I think this structure could be helpful:
> 
> === timecode
> We’ve made many starts and stops at defining how to store timecode in 
> Matroska but haven’t found consensus or resolution on those attempts. 
> With the Metadata Element I think a timecode value could be stored such as
> 
> Cluster/
> Timestamp=01:00:00.000
> BlockGroup/
> Block/
> ...
> Metadata/
> MetadataName=“timecode"
> MetadataString="01:23:45;12”

while I think that frame side data can be useful for the DPX scenario 
mentioned later, I see problems with storing timecode information that 
way. Shall timecode be attached to the video or audio track? Shall there 
be some sub-classification for VITC/LTC/other timecode sources?

Also I would prefer the timecode value to be stored as a number instead 
of a string representation, for the same reason that the Cluster 
Timestamp element uses a numerical representation: It makes processing a 
lot easier.

Best regards,
Tobias