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Re: Action-28: updated syntax document with time formats

From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Thu, 5 Feb 2009 13:05:23 +1100
Message-ID: <2c0e02830902041805t4cfe8150s412fa90bd56c814e@mail.gmail.com>
To: Conrad Parker <conrad@metadecks.org>
Cc: Media Fragment <public-media-fragment@w3.org>

On Thu, Feb 5, 2009 at 11:39 AM, Conrad Parker <conrad@metadecks.org> wrote:
> 2009/2/5 Silvia Pfeiffer <silviapfeiffer1@gmail.com>:
>>
>> I totally agree with not using a single colon as a separator. I just
>> thought that it would make sense to specify in a URL which time scheme
>> we are using (as we did in the temporal URIs). However, if there is
>> already a widespread consensus on specifying time scheme changes by
>> using different characters, then we may as well use that. I am only
>> afraid that people will make mistakes easily.
>
> In the avid cmx syntax as I understand it, the frame separator is not
> used to signify which time scheme is used, but to signify which field
> of an interlaced frame is used in an edit.
>
> The syntax that Jack wrote on the wiki does include the timescheme
> name (just as we have for temporal URIs).

In the wiki, we distiguish between "smpte-25" | "smpte-30" | "smpte-30-drop".

In the avid cmx syntax "presence of a period in the bottom of the
separator indicates NON Drop frame timecode, and presences of the
comma (dropping below the line ) indicates Drop Frame timecode". So,
at least a part of the avid cmx syntax is about dealing with drop
frame time code or not.

As for the other part of the cmx syntax which allows addressing of the
interlacing fields, I guess it is necessary from an editing viewpoint
what with digital interlacing formats around and such.

Cheers,
Silvia.
Received on Thursday, 5 February 2009 02:05:59 GMT

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