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

From: Thierry MICHEL <tmichel@w3.org>
Date: Sat, 29 Jan 2011 15:28:44 +0100
Message-ID: <4D44241C.4070104@w3.org>
To: Joakim Söderberg <joakim.soderberg@ericsson.com>
CC: Daniel Park <soohongp@gmail.com>, "public-media-annotation@w3.org" <public-media-annotation@w3.org>

> 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
Received on Saturday, 29 January 2011 14:29:03 GMT

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