Re: [Banshee-List] Mirage - Automatic Playlist Generation Plugin

[Dominik Schnitzer <dominik schnitzer at>]

David Nielsen wrote:
> fre, 31 08 2007 kl. 16:21 +0200, skrev Dominik Schnitzer:
> > Hi,
> > After all your songs are analyzed. You can generate playlists by
> > dragging a seed song on the Playlist Generator item in banshee. Mirage
> > then searches its database for similar sounding songs. The 5 top-hits
> > are then put in the playlist.
>
> I appear to have some issues making that part work, I compiled mirage on
> Fedora 7 against Banshee SVN on an x86_64 box and when ever I drag a
> song to the playlist generator all I get is that one song. This happens
> even when I use some of the same music as you displayed in your
> demonstration video (Indidginus more specifically). I assume the fact
> that all my music is in the FLAC format might have something do do with
> this.

Hi,

you're right.. At the moment the "mirage-decoder" shellscript only
handles  ogg/mp3/aac/wav files - so your songs were not analyzed. You
could rewrite it to handle FLAC too.

Then you would need to reset your Banshee database.
# rm -f ~/.mirage/*

and

# sqlite3 ~/.config/banshee/banshee.db
OR (depending on your banshee version)
# sqlite3 ~/.gnome2/banshee/banshee.db
THEN
> delete from MirageProcessed;
> .quit


> >   * MPG123/FAAD/OGG123/SOX are reguired because of performance reasons.
> > Since Mirage needs to decode every music piece in order to analyze it
> > the fastest decoders available are needed. I.e. using the gstreamer
> > framework would have been really nice, but in the end it was too slow
> > :-/ Even libmad is about 4-5 times slower than MPG123, just to name an
> > example. Opinions on this issue are welcome!
>
> Speed sadly isn't the only problem, by going with a GStreamer based
> solution you'd be able to support any format Banshee already plays not
> to mention it would make packaging Mirage easier for distribtions that
> have to take US law seriously (no mp3 support allowed e.g.). 

Ok, I guess I'll think about a Gstreamer solution... The nice thing 
about mpg123 is that it is so fast in decoding and downsampling (22khz, 
mono) a piece:

"mpg123 -2 -m out.wav file.mp3"

is done in 1-2secs. Gstreamer takes about 32secs with audioresample and 
the mad plugin.
I'll have a look at an adequate gstreamer pipe.. Maybe there is 
something wrong with my gstreamer pipe.

> If the numbers from my database, around 2600 songs all in FLAC is any
> indication of the performance it ran the analysis in around 30 secs
> (seems suspect - very suspect especially since it doesn't work), even if
> performance problems are unsolvable I think I'd favor a solution based
> on GStreamer just based on those to points. It's a one off action to
> scan the database anyways and after that I assume you just analyse songs
> that are added seperately.

Usually analyzing a collection of that size takes about 6-8 hours (with
mpg123 doing the job). It actually depends how long flac -> 22khz, mono
wav takes.

> > It would be very cool, if someone could try this out and give some
> > feedback. I know it is far from being perfect but hey, it somehow works
> > :). Patches are welcome. I am planning to improve and work on this,
> > since smooth integration in Banshee and functionality like this would be
> > cool.
>
> I can't offer a patch but I will translate this mother into Danish for
> you once such support is added.

That would be cool. I've added a roadmap item on the homepage where I'll
start collecting plans for the next version. Internationalization
support is on it :-)

thanks for your feedback,
domi.