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Re: RE : RE : Recapitulation of ma:format vs. ma:compression.

From: David Singer <singer@apple.com>
Date: Mon, 31 Jan 2011 09:12:15 -0800
Cc: "tmichel@w3.org" <tmichel@w3.org>, Joakim Söderberg <joakim.soderberg@ericsson.com>, Daniel Park <soohongp@gmail.com>, "public-media-annotation@w3.org" <public-media-annotation@w3.org>
Message-Id: <4CB3E301-D550-42F3-A775-B3721568A780@apple.com>
To: "Evain, Jean-Pierre" <evain@ebu.ch>
Hi

OK, so it looks as though we are converging.  How about this text?

compression

(attName="compression", attValue="URI#Name")

The compression type used. For container files (e.g., QuickTime, AVI), the compression is not defined by the format, as a container file can have several tracks that each use different encodings. In such a case, several compression instances SHOULD be used. Thus, querying the compression property of the track media fragments will return different values for each track fragment.   The indicator is a pair of values, separated by a hash sign ("#"). The first is a URI that identifies the naming convention used for the second parameter, which is a string name from that convention.  A URL is preferred for the URI, and if it is used, it (a) should contain a date in the form mmyyyy, indicating that the owner of the domain in the URL agreed to its use as a label around that date and (b) should be de-referencable, yielding an informative resource about the naming convention.

Note that for some container files, the format parameter can also carry an extended MIME type to document this; see [RFC 4281] for one such instance.

Examples:
   compression="urn:example-org:codingnames2010#ITU-H264"
   compression="http://example.net/012011/standards/codecs.htm#G711"
where ITU-H264 and G711 are defined by example.org (who also defined a URN to identify their naming conventions), and by example.net (who use a URL to identify theirs).

Glad your travels were good.

On Jan 30, 2011, at 22:28 , Evain, Jean-Pierre wrote:

> Hi David,
> 
> I see you had a safe trip back. Me too but I arrived quite late in Geneva with Touradj.
> 
> As discussed, fine by me as # constructs are URI and is directly compatible with the way the ontology has been written. 
> 
> However only one additional comment: I would suggest we recommend the use of ea dereferencable URIs, which use a URL basis instead of namespaces.  For example, EBU Skos classification schemes are available as permanent web resources and use URL based URIs.
> 
> Regards,
> 
> Jean-Pierre
> ________________________________________
> De : public-media-annotation-request@w3.org [public-media-annotation-request@w3.org] de la part de David Singer [singer@apple.com]
> Date d'envoi : samedi, 29. janvier 2011 23:26
> Ā : tmichel@w3.org
> Cc : Joakim Söderberg; Daniel Park; public-media-annotation@w3.org
> Objet : Re: RE : Recapitulation of ma:format vs. ma:compression.
> 
> In further discussion, it seems that using anchor syntax and a # as the separator is cleaner.  Can we change to
> 
>>> attValue="URI#Name"
> 
>>>    compression="urn:example-org:codingnames2010#ITU-H264"
>>>    compression="http://example.net/standards/codecs#G711"
> 
> with corresponding changes to the text?
> 
> On Jan 29, 2011, at 23:28 , Thierry MICHEL wrote:
> 
>> 
>>> compression
>>> 
>>> (attName="compression", attValue="URI" | "String")
>>> 
>>> The compression type used. For container files (e.g., QuickTime, AVI), the compression is not defined by the format, as a container file can have several tracks that each use different encodings. In such a case, several compression instances SHOULD be used. Thus, querying the compression property of the track media fragments will return different values for each track fragment. Note: it is possible to use an extendedMIME type as the value for this property, see [RFC 4281].
>>> 
>>> 
>>> 
>>> suggested change to
>>> 
>>> compression
>>> 
>>> (attName="compression", attValue="URI, String")
>>> 
>>> The compression type used. For container files (e.g., QuickTime, AVI), the compression is not defined by the format, as a container file can have several tracks that each use different encodings. In such a case, several compression instances SHOULD be used. Thus, querying the compression property of the track media fragments will return different values for each track fragment.   The indicator is a pair of values, separated by a comma. The first is a URI that identifies the naming convention used for the second parameter, which is a string.  For some container files, the format parameter can also carry an extended MIME type to document this; see [RFC 4281] for one such instance.
>>> 
>>> Examples:
>>>    compression="urn:example-org:codingnames2010, ITU-H264"
>>>    compression="http://example.net/standards/codecs, G711"
>>> where ITU-H264 and G711 are defined by example.org (who also defined a URN to identify their naming conventions), and by example.net (who use a URL to identify theirs).
>>> 
>> 
>> 
>> Updated the compression Statement.
>> http://dev.w3.org/2008/video/mediaann/mediaont-1.0/mediaont-1.0.html#core-property-lists
>> 
>> For the examples; I have added a link to the following section, which contains the examples.
>> 
>> 5.1.3.1 Examples for the compression property
>> 
>> Best,
>> 
>> Thierry
>> 
> 
> David Singer
> Multimedia and Software Standards, Apple Inc.

David Singer
Multimedia and Software Standards, Apple Inc.
Received on Monday, 31 January 2011 17:12:52 GMT

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