[gst-devel] Some advice

[Michael Smith]

On Mon, Sep 22, 2008 at 1:41 AM, Colin Guthrie <gmane at colin.guthr.ie> wrote:
> Hi,
>
> I have been working on hacking the phonon-gstreamer backend recently and
> as I'm a significant degree short of even having a rudimentary knowledge
> of gstreamer, this was a bit of an uphill struggle.
>
> I've managed to get a few things working now, but I have a couple of
> questions that hopefully some of the development gurus can answer me.
>
>
> 1) Is it possible to find out which sink is really used when you use
> gconfsink, autoaudiosink or halsink?

These are all bins (they contain other elements); so you can just
iterate (possibly recursively) over all the elements in them, looking
for sinks, and then look at the type of the sink. autoaudiosink and
halsink are both pretty easy, but gconfsink lets you have a
more-or-less arbitrary bin, which could even contain multiple sinks
(though that would be rare).

>
>
> 2) When streaming data from shoutcast, it is possible to decode the
> StreamTitle= header via icydemux. I have hacked phonon-gstreamer backed
> to do this now (in a similar way to how playbin does it). However it
> only extracts the title.
>
> When I use the Xine backend it appears to be able to extract inline
> metadata out of the stream content itself (e.g. when it finds a vorbis
> comment header or an id3 tag). That's as much as I can tell from
> observation. I've hacked the phonon-gstreamer to be able to "guess" the
> artist name from the StreamTitle but it's really not very nice. So my
> main question is, can the decoders handle inline metadata decoding and
> if so how can I enabled this?
>

I guess it'd be useful to point us at a stream that behaves like this.

'icydemux' will extract metadata properly from shoutcast streams (so
long as the source is providing this data). Vorbis streams have inline
metadata that should be handled automatically, without anything
special being needed. I've never seen inline id3 being streamed, nor
have I ever seen software that would handle it at all.

So you shouldn't need to do anything special apart from requesting the
http sources to get shoutcast-style metadata.

Mike