W3C home > Mailing lists > Public > public-media-annotation@w3.org > April 2010

Re: [W3C Media Annotation WG] Request for Expert Review (API)

From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Tue, 20 Apr 2010 00:47:02 +1000
Message-ID: <q2u2c0e02831004190747l411ef5ebyb2d6d3f9830e5dd1@mail.gmail.com>
To: Pierre-Antoine Champin <pierre-antoine.champin@liris.cnrs.fr>
Cc: "Chris.Poppe@ugent.be" <Chris.Poppe@ugent.be>, "public-media-annotation@w3.org" <public-media-annotation@w3.org>
On Mon, Apr 19, 2010 at 11:10 PM, Pierre-Antoine Champin
<pierre-antoine.champin@liris.cnrs.fr> wrote:
> Hi Silvia and all,
> On 16/04/2010 01:52, Silvia Pfeiffer wrote:
>> Hi Chris,
>> Thanks for the clarification of how the interface seems to have been designed.
>> I can now see how you have designed the interface to associate
>> multiple metadata resources with one media resource through the
>> function:
>>   boolean setContext(in DOMString mediaResource, in optional Object[]
>> metadataSources );
>> From what you are describing, the order in which the metadataSources
>> are given in the second parameter will be important, since getProperty
>> will return for every one of these resource the value of the requested
>> propertyName.
> I'm not sure this was implied here. I don't remember us discussing the
> *order* of multiple return values, but indeed, relating it to the order
> of metadataSources seems like a reasonable default choice...
>> I must admit I am uncomfortable with an API that chunks all the
>> possible metadata formats together in one return object. I would
>> rather that the list of metadata resources is administrated at a
>> higher level and not within the Media Annotations API.
> with the proposed API, nothing prevents you from creating separate
> MAResource for separate metadata sources, if you want to keep them
> separate...
> But you can also create one that aggregate them, if you do not care for
> the provenance, e.g. if you equaly trust the different sources.
> Furthermore, it seems to me that your examples below make the asumption
> that we know in advance which subset of metadata is contained in each
> metadata source, which may not always be the case.

The assumption is that the Media Annotation API provides a certain set
of metadata - the standard set. Whether they are all filled with
values is a different matter. I think it is very important to be able
to ask for each resource what data is available for it - even if
there's none.

> As for the language attribute, it will not always be the case that a
> metadata source will use a single language for all its properties. For
> example, an RDF file may contain :
> <video.ogg> dc:title
>  "Planet of the apes"@en,
>  "La plančte des singes"@fr .
> So you can't really escape the per-value language attribute, can you?

Generally, you will not get a mixed language metadata file. I don't
know where you take your example from. I am following general practice
in libraries and other institutes that create metadata and they will
keep metadata descriptions for the same media resource separate as
much as possible. You can, of course, make up a metadata format that
can have multiple mixed language annotations, but I am finding those
rather unusable and am not sure we should be supporting it in the API.

Received on Monday, 19 April 2010 14:47:56 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 21:17:37 UTC