RE: PFWG review of Ontology for Media Resource 1.0 http://www.w3.org/TR/2009/WD-mediaont-10-20090618/

Dear all,

As discussed in the telco on Sept. 2 please find below is a proposal for our response to the PFWG feedback.

Best regards,
Werner

> Comment 1: Property for alternate versions
> 
> We request that you provide a property to indicate the 
> location of alternate versions (complete with the MIME type 
> and location, and keeping in mind that alternate versions of 
> resources often have different granularities so have to be 
> referenced carefully). This might correspond to the DCMI 
> Metadata Terms hasFormat 
> http://www.w3.org/TR/2009/WD-mediaont-10-20090618/ or 
> isFormatOf 
> http://dublincore.org/documents/dcmi-terms/#terms-isFormatOf. 
> It is possible that the ma:relation property fulfills this 
> function but if so this needs to be documented more clearly, 
> including explanation of accessibility use cases (ability to 
> find alternate formats, including transcriptions, captions, 
> etc. of the "same" media).

The basic functionality for getting alternate versions is indeed covered by ma:relation. The value of the ma:relation property contains the URI of the alternate resource. It's MIME type, location and other properties can be queried by a subsequent request for annotations about the URI of the alternate content. The ma:relation property has a qualifier that allows to specify the type of relation. The definition of these lists of qualifiers is currently ongoing. 

We have already a note about accessibility metadata on our Wiki page for possible properties to be considered in future [1], mentioning links to transcripts, audio description of video etc. We plan to review whether the mechanism provided by ma:relation and qualifiers is sufficient to cover these requirements and will consider additional properties if necessary.

> Comment 2: Property for dependencies
> 
> It would be important to have a property corresponding to 
> DCMI Metadata Terms requires 
> http://dublincore.org/documents/dcmi-terms/#terms-requires. 
> This would be to indicate if the media requires something 
> else to be played. If it requires something else known to be 
> inaccessible on the user's system, then the media could be 
> known to be unplayable from its metadata.

We have tried to restrict technical properties to a minimum and included only those well motivated by the collected use cases [2]. We have not considered properties that are specific to a small set of content types or that are only needed by the player itself. Of course, as you mentioned, a property such as terms:requires could be useful in some for content selection before. I have added it to the list of possible future properties and we will discuss about it in due time.

[1] http://www.w3.org/2008/WebVideo/Annotations/wiki/Candidate_Additional_Elements
[2] http://www.w3.org/TR/media-annot-reqs/

Received on Wednesday, 2 September 2009 17:36:53 UTC