Re: How to actually use mp3-transcoding

[Jens Georg <mail jensge org>]

On Mi, 2012-11-07 at 15:45 +0200, Mehmet Giritli wrote:
> On Sun, 2012-10-28 at 09:48 +0100, Jens Georg wrote:
> > On So, 2012-10-28 at 09:19 +0200, Mehmet Giritli wrote:
> > > Hello,
> > > 
> > > I'm trying to use winamp on windows with the ml_dlna plugin to play
> > > files from a rygel server. The music library is entirely flac and winamp
> > > can not stream flacs (it can play local flacs tough). So, I'm tring to
> > > transcode flac to mp3. I enabled it in the config file but winamp still
> > > trying to get flacs and fail since it cant do that.
> > > 
> > > So, my question is, how is this supposed to work? I wrote to the author
> > > of the plugin and he is suggesting that "rygel has to exchange the
> > > FLAC-stream-urls with MP3-transcoding-stream-urls in its DLNA publishing
> > > service."
> > 
> > Sorry, that's just wrong. In DLNA/UPnP-AV, the _controlling_ party (in
> > this case ml_dlna) is responsible for choosing the most compatible
> > stream and not the server for working around broken implementations.
> > It's not our task to present any random renderer with just one
> > compatible stream, we would need to implement half a controller for
> > that. Instead we offer a list of streams in various formats.
> > 
> > Saying something like this is rather a sign that the "DLNA" in ml_dlna
> > is a false claim.
> > 
> 
> Hi Jens,
> 
> I have been communicating with the author of the plugin and he managed
> to get it working with rygel using transcoded streams. But there are
> some problems still. First of all, let me quote this from the author who
> tested various other programs with rygel:
> 
> "I've tried Windows Media Player (DLNA certificated), VLC Player and
> foobar2000 to listen FLAC files. All these programs are requesting the
> published (flac) files. They also not discovering transcoding streams.

I don't know which WMP he is talking of, but the WMP on my rather
pristine W7 ultimate picks the MP3 stream just fine.

And I don't know what's wrong with the other two picking FLAC, both of
them can play it. You should prefer DLNA.ORG_CI=01 files if you support
them (01 meaning non-transcoded).

>  I
> think they make the same mistake I did before and only look for the
> first published stream per file. For other systems it would be helpful
> to have a rygel config to control the order of published streams. MP3
> should be on first place, because this is the most common codec for all
> devices."

That's just an anecdotal assumption. MP3 is not mandatory in DLNA.

> Of course, they might all be broken I guess. But most important problem
> that remains is about meta data:
> 
> "An other point are the published meta data and file names. If you use
> ml_dlna you'll see that all mp3-transcoded files are named as MP3.mp3 in
> playlist. The transcoded files are not containing any meta data to make
> Winamp display the right artist and title so Winamp displays the file
> name - in this case the end of the stream url. So, it would be nice to
> rename the end part of transcoded streams to the original file name (or
> some meta data) followed by the extension (.mp3). Of course I send the
> correct artist and title to playlist but Winamp rename the entry with
> received meta data or file name if you start to play."

Well that's what happens when you plug foreign support on something
that's used to use files only.

> Is it possible at all to pack-in meta data for transcoded files? Or is
> this a feature not yet implemented?

I'm not sure if we'll ever implement that. Most implementations just
pick the meta-data from the XML.