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Re: Review of 'Use Cases and Requirements for Ontology and API for Media Object 1.0', Working Draft 19 January 2009

From: Yves Raimond <yves.raimond@bbc.co.uk>
Date: Fri, 6 Feb 2009 10:51:17 +0000
Message-ID: <82593ac00902060251s29ff502ej6f8e9c37ef4f8add@mail.gmail.com>
To: Felix Sasaki <fsasaki@w3.org>
Cc: Michael Hausenblas <michael.hausenblas@deri.org>, public-media-annotation@w3.org, public-media-fragment@w3.org

Hello!

> many thanks for your description of FRBR. I am aware of its usage goals in
> the library and archives world, though I do not know actual implementations
> of it in the area of video. With implementations I mean applications which
> make use of e.g. the distinction of content and item which you described
> below, e.g. for search. Do you know any of these we could look at?

Well, BBC Programmes or BBC iPlayer for example. A single programme
can have many versions, which are the actual items. See
http://www.bbc.co.uk/ontologies/programmes/2008-02-28.shtml for a more
formal definition of that.
I think most relational db backing popular video websites use a
similar distinction. I *never* (apart from Magnatune) saw a db schema
not reflecting that distinction.

Cheers!
y

>
> Note also that have no consensus to take the related requirement into
> account
> http://www.w3.org/TR/2009/WD-media-annot-reqs-20090119/#req-r07
> which, by the way, cites FRBR.
> For the use case of "Audiovisual archive as a Cultural Heritage Institution"
> http://www.w3.org/TR/2009/WD-media-annot-reqs-20090119/#uc-cultural-heritage-institutions
> This requirement is a crucial one, but
> a) we may not be able to implement this use case in the given amount of time
> - according to our charter we should be finished in about 10 months ..., and
> b) with several abtraction layers we face the challenge of loosing
> simplicity for people who want to implement simple applications as described
> at
> http://www.w3.org/2008/10/24-mediaann-minutes.html#item01
> or as exemplified at
> http://www.w3.org/2008/Talks/video-capgemini/#(16)
> http://www.w3.org/2008/03/metadata_demo
> http://www.w3.org/2008/03/meta_functions.js
>
> Regards,
>
> Felix
>
>
> Yves Raimond さんは書きました:
>>
>> Hello!
>>
>> On Thu, Feb 5, 2009 at 1:43 AM, Felix Sasaki <fsasaki@w3.org> wrote:
>>
>>>
>>> Hello Michael,
>>>
>>> many thanks for the follow up! Some replies below.
>>>
>>> Michael Hausenblas wrote:
>>>
>>>>
>>>> Felix,
>>>>
>>>> Most of the stuff seems sorted, thanks. Remaining points inline:
>>>>
>>>>
>>>>
>>>>>
>>>>> I think that the paragraph
>>>>> "An important aspect of the above figure is that everything visualized
>>>>> above the API is left to applications, like: languages for simple or
>>>>> complex queries, analysis of user preferences (like "preferring movies
>>>>> with actor X and suitable for children"), or other mechanisms for
>>>>> accessing metadata. The ontology and the API provide merely a basic,
>>>>> simple means of interoperability for such applications."
>>>>> Tries to answer some of your questions.
>>>>>
>>>>>
>>>>
>>>> Some, yes ;)
>>>>
>>>> Seriously, I *think* it would be good to have the ontology as the
>>>> primary
>>>> model and derive the API from it (automagically?) if possible. I must
>>>> admit
>>>> that I still didn't entirely grok how these two things play together.
>>>> Assume
>>>> for a second that I'm a total noob - how'd you explain that in some
>>>> simple
>>>> language?
>>>>
>>>>
>>>
>>> The ontology describes relations between properties in existing formats.
>>> As an example of the relation description see the table at
>>>
>>> http://dev.w3.org/cvsweb/~checkout~/2008/video/mediaann/mediaont-1.0/mapping_table_common.xls?rev=1.3&content-type=text/plain
>>> This table (and our working group) has put XMP into the focus, see
>>> leftmost column. That means that all other formats are related to XMP as
>>> much as possible.
>>>
>>> The ontology which we will produce may be
>>> 1) just this table, in a more readable and verified version, "verified"
>>> meaning: checking with users and implementers of the format and XMP
>>> specialists whether our description of the relations is appropriate
>>> 2) an ontology using a formal language like RDF, or an RDF-based
>>> vocabulary (like SKOS), an XML-based format with an addition formal
>>> semantics, some other language etc.
>>>
>>> Currently we have no consensus in the Working Group whether we should do
>>> only 1), only 2), both 1) and 2) and make 2) the normative version, both
>>> 1) and 2) and make 1) the normative version, etc. This is especially my
>>> fault ;) , since I have the use case of a client-side API, e.g.
>>> JavaScript in a browser, in mind, which implements the mappings between
>>> formats. Such an API can be built easily *by hand*, that is by reading
>>> the prose in the table from 1), but IMO it cannot be expected that such
>>> an API would process RDF or another formal language. Or to put it
>>> differently: we have different user communities with different usage
>>> scenarios for the ontology in mind, and it is hard to find a middle
>>> ground. The automatic derivation of the API sounds interesting in
>>> theory, but I have a hard to imagine it in practice.
>>>
>>>
>>>>>>
>>>>>> + Regarding '6.7 Requirement r07: Introducing several abstraction
>>>>>> levels in
>>>>>> the ontology' I'd say this is an absolute must.
>>>>>>
>>>>>>
>>>>>
>>>>> Do you have any existing implemention we could look at to be able to
>>>>> judge the efforts of this?
>>>>>
>>>>>
>>>>
>>>> Well, yes, I guess so, see [1] and [2]; its from the audio domain and
>>>> the
>>>> chap behind it, Yves Raimond, is lurking here around as well, so he may
>>>> be
>>>> able to chip in ;)
>>>>
>>>>
>>>
>>> It would be great to get more information about this. I have a hard time
>>> to grasp the abstraction layers, and to understand how one can make use
>>> of them in [2]. Some explanation would be really helpful.
>>>
>>
>> Well, [2] is perhaps not the clearer reference about FRBR :-)
>> Anyway, to summarise briefly, when annotating media, you can't simply
>> consider the actual multimedia item, you need to consider more
>> abstraction layers than that. The first obvious layering is the
>> distinction between the content (the actual signal) and the item (the
>> CD on my shelf, the MP3 on my hard drive). You may want to describe
>> the content without having access to the actual item, or you may want
>> to describe the content once for many different items. These two
>> layers are absolutely necessary in a multimedia annotation context,
>> IMHO.
>>
>> FRBR (on which the Music Ontology is (loosely) based) goes a bit
>> beyond that. It defines four abstraction layers:  Work (J. S. Bach's
>> Six suites for unaccompanied cello),
>> Expression (performance by Janos Starker in 1963), Manifestation
>> (recordings released on 33 1/3 rpm sound discs in 1965 by Mercury),
>> and Item (my FLAC rip of that disc).
>>
>> FRBR in a video context is a bit trickier, but the distinction between
>> content and item should at least *really* be there.
>>
>> Kind regards,
>> y
>>
>>
>>>>
>>>> Mostly I'd recommend to focus on FRBR [3], but I guess the real expert
>>>> is
>>>> actually Yves. Ah, I'll CC him and see what happens ...
>>>>
>>>>
>>>>
>>>>>>
>>>>>> + the TOC is not well-formatted, although pubrule-checker [2] seems
>>>>>> not to
>>>>>> complain - rather use use <ol> and <li>
>>>>>>
>>>>>>
>>>>>>
>>>>>
>>>>> mm ... I checked
>>>>>
>>>>> http://validator.w3.org/check?uri=http://www.w3.org/TR/2009/WD-media-annot-req
>>>>> s-20090119/
>>>>> and did not see any problems. Could you point me to the markup part
>>>>> which you think has a problem?
>>>>>
>>>>>
>>>>
>>>> Well, true. As I said. It's perfectly *valid*, it's about the markup you
>>>> are
>>>> using (list rather <p> + <br/>) ...
>>>>
>>>>
>>>
>>> ah, now I understand. Many thanks for checking, we will fix that for the
>>> next publication.
>>>
>>>
>>>>>
>>>>> I did not see any comments on the requirements which I think are the
>>>>> most important "message" of the WD. Do you think these need a revision
>>>>> or are stable?
>>>>>
>>>>>
>>>>
>>>> Seems pretty stable, beside my comments ;)
>>>>
>>>>
>>>
>>> Thanks. So let me phrase this as a question: except that you regard r07
>>> as important ("several abstraction layers"), do you or somebody else
>>> from the Media Fragments Working Group think there are other
>>> requirements we should take into account? Could you reply with "no" on
>>> behalf of your Working Group?
>>>
>>> It would also be great to get feedback from you about our conversation:
>>>
>>> [
>>>
>>>>
>>>> If you can't talk about the
>>>> different abstraction layers, I guess the effort is pretty worthless.
>>>>
>>>>
>>>
>>> At the TPAC meeting in October we had a presentation from a video search
>>> engine with not more than *five*, "flat" properties, see
>>> http://www.w3.org/2008/10/24-mediaann-minutes.html#item01
>>> I think we saw a metadata mapping which was very useful and worth it, so
>>> I would disagree with your statement above.
>>> ]
>>>
>>> that is, your feedback about the example of a simple approach I
>>> mentioned. Although you stated that without different abstraction layers
>>> you regard the effort as worthless, there seem to be even rather large
>>> applications which work without abstraction layers.
>>>
>>> Regards,
>>>
>>> Felix
>>>
>>>
>>>>
>>>> Cheers,
>>>>      Michael
>>>>
>>>> [1]
>>>>
>>>> http://wiki.musicontology.com/index.php/Structural_annotations_of_%22Can%27t
>>>> _buy_me_love%22_by_the_Beatles
>>>> [2] http://dbtune.org/henry/
>>>> [3] http://www.loc.gov/cds/downloads/FRBR.PDF
>>>>
>>>>
>>>>
>>>
>>>
>
>
>
>
Received on Friday, 6 February 2009 10:53:15 GMT

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