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

["Juan A." Suárez Romero <jasuarez igalia com>]

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.


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.