Re: [PATCH] tracker: use "nfo" ontologies for media

[Lionel Landwerlin <lionel g landwerlin linux intel com>]

On Thu, 2011-02-03 at 11:38 +0100, Juan A. Suárez Romero wrote:
> On Thu, 2011-02-03 at 11:53 +0200, Jussi Kukkonen wrote:
> > The ontologies are a bit weird/incomplete here: nmm:Video is a
> > superclass of both nfo:Video and nfo:Audio. This makes some sense on
> > it's own but is fairly inconsistent with the lack of nmm:Audio --
> > there's no way to define non-music audio (say a podcast) in the
> > multimedia namespace so the only way to do that is with nfo:Audio
> > which
> > then gets tangled up with video...
> > 
> > Practical alternatives include
> >   A) more complex matching (grilo "audio" would mean something that is
> > "nfo:Audio" but is _not_ "nfo:Video").
> >   B) pretend all audio is music: IOW match only "nmm:MusicPiece". I'd
> > still continue using nfo-namespace for other media.
> > 
> > Option B is what most people seem to be doing at the moment -- the
> > downside of this is that if anyone later tries to do the right thing,
> > their data will appear broken in other apps (this is how I found the
> > problem in he first place -- a tracker miner doesn't necessarily know
> > if
> > an audio item is music so I thought nfo:Audio made perfect sense in
> > that
> > situation). Any opinions? 
> 
> 
> I do not have a deep understanding about how miners works. I guess that
> miners crawling a video file mark it as nfo:Video & nfo:Audio just
> because it is a video file, and then inspect the tags to mark them as
> nmm:Video.
> 
> I guess the same happens for audio files: they are nfo:Audio and, if
> they have tags, then are marked as nmm:MusicPiece[1].
> 
> The point is that I think miners can't distinguish between a music piece
> and other kind of audios, like podcasts. That is why nmm:Audio probably
> doesn't make too much sense.
> 

What make the distinction is the context in which you crawl the data. If
you have a podcast crawler then it will identify its audio files as
podcast where a filesystem crawler will identify the same files as
MusicPiece or Audio.

> 
> So regarding the alternatives, so far I was following the (b) approach.
> But I'm not sure if *all* audio will be tagged as nmm:MusicPiece by
> tracker. What happens with a file with no tags at all? If actually all
> miners tag audio files as nmm:MusicPiece then I would go with this
> option.
> 
> Else, I would go with option (a). In fact, I would go with (a) right now
> if nmm:MusicPiece were a nfo:Audio, but it isnt.
> 
> 	J.A.
> 
> 
> 
> [1] I know about the bug you filed: nmm:MusicPiece inherits from
> nfo:Media instead of nfo:Audio.
> 

Indeed the ontology is confusing...