[Nepomuk] Bangarang player media library

[Evgeny Egorochkin]

В сообщении от Воскресенье 31 января 2010 19:12:32 автор Jamboarder написал:
> Thanks much for the heads up Evgeny.
> 
> > From: Evgeny Egorochkin
> > I have uncovered another issue with Bangarang, It seems to have it's own
> > media library scanner and metadata extractor which also marks song
> > metadata as user- created, and not automatically generated.
> 
> Bangarang doesn't really have an explicit media scanner function.  It just
>  updates nepomuk whenever a file with extractable metadata is opened or
>  when a user updates metadata for a media resource.

This is what I meant. That it adds media metadata generated from tags on 
occasion.

>  It uses the methods
>  (setProperty, addType and setTypes) of Nepomuk::Resource to set/update
>  data. Am I using the api incorrectly?

Not really incorectly. However, it conflicts with nepomuks file indexer which 
adds another copy of metadata extracted from tags.

> > A much better solution would be to tell nepomuk which files to index and
> > add any of you custom data extractors into libstreamanalyzer or at least
> > refactor them as libstreamanalyzer plugins.
> 
> Sounds good. That makes sense for metadata that is techinically extractable
>  from the file itself. 

This is what I'm talking about.

>  Since there's quite a lot of metadata that may or
>  may not be extractable there will still be a need for Bangarang to
>  maintain the in-context update of the nepomuk resource.

You're handling user-generated metadata just fine.

>  At the moment, when updating nepomuk data, Bangarang doesn't distinguish 
between techinically extractable file metadata and non-extractable metadata.


>  Video
>  metadata is the prime example.  The entirety of the the video metadata in
>  Bangarang right now is user created. I hope to add some support of video
>  file metadata formats in the 2.0 version.  I like the idea of refactoring
>  the file metadata extractors as libstreamanalyser plugins, but I'll still
>  need to maintain functionality for in-context user-created metadata that
>  is not technically extractable.
> 
> > You would get the same or better functionality, contribute to nepomuk and
> > avoid lots of pitfalls like your custom extractors and file indexing
> > service adding what essentially is 2 copies of the same data.
> 
> That seems a little odd.  Does that mean a duplicate triple for the same
>  resource is created when setProperty is called on an existing resource
>  property?

Not at all. Ontology allows you to specify several performers/artists for 
media, which is fine, unless 2 different services create their own copy of 
performer metadata.

>  I can kinda see the reasoning for setting it to user-created but
>  it seams like it shouldn't duplicate it.  Is there anyway for an app to
>  just update the automatically generated triples since, whether strigi or
>  Bangarang or any other app does it, the data is still automatically
>  generated from the file metadata.

I think we need to add such an API call to nepomuk.

> In the short term I'd like to sort out this duplicate issue as a potential
>  bugfix.

We'd need Sebastian Trueg's input on how to handle this the best way.

>  Then, if it still makes sense, in the medium term (version 2.0)
>  I'd like to try for the libstreamanalyser solution.

I think it will be easier for you as I'm planning a major media overhaul... so 
maybe it will take no effort on your part at all :)

> > I can help you with strigi part, and I hope Sebastian can find a way to
> > let Bangarang extend the media collection via some nepomuk API call.
> 
> Thanks much Evgeny.   A quick first thought is that since a
>  libstreamanalyser plugin would result in a split in the code path for
>  writing to nepomuk in Bangarang, to keep the user feedback consistent I'll
>  probably need some progress feedback. Does that already exist?

I hope to have Sebastian's input on this too...

>  Also, probably a silly question but can the plugin be delivered at app 
install  time? Or does it have to be delivered at strigi install time?

You can add your plugins anytime.
-- 
Evgeny