[gst-devel] DVD Navigation progress

[Mathrick]

W liście z wto, 20-01-2004, godz. 14:22, Jan Schmidt pisze: 
> Hi all,
> 
> I'm sending in a patch (attached) with what I have so far rather than
> just committing it, because I've touched a few things and would like
> comments. If I get none, I'll just commit it.

Your current threats on IRC about not commiting seem to be contrary to
that statement, but whatever ;)

> * There is no way to change audio/video/subtitle tracks apart from
> unplugging the mpegdemux->mpeg2subt link and reconnecting it to a
> different pad on mpegdemux
[snip]
> 	Implementing the 'change language/format' etc features of DVDs where
> the user can select a different video/audio/subtitle stream to watch. 
> 		- How can this be done? I could add new 'video_nav', 'audio_nav' and
> 'subtitle_nav' pads to mpegdemux and have navigation events select the
> streamids that are sent to those pads.
> 		- alternatively there may be some system of moving the
> video/audio/subtitle decoders links between the 'sometimes' pads of
> mpegdemux depending on the chosen stream. Ideally I'd like it all to
> work without special application support, but I don't know.

[Not commenting on actual code, just random ideas]

Selecting tracks seems to be possible using switch element, ie. link all
tracks of given type to single switch, and then make it handle 'track
select' event. Possible problems:

- Worse track identification than with dedicated mpegdemux solution. But
then, mpegdemux could just emit appropriate tags containing that info

- Issues with autoplugging. Yep, this one is much tougher, and I don't
even want to try convincing Benjamin it should be done with multiple
pads ;). Yet there is a question: how much of that funtionality is
possible to achieve w/o special support? Apps not taking multiple tracks
into account can't offer provision to select them whatsoever, so maybe
autoplugging shouldn't go so far to try providing it anyway?

Cheers,
Maciej

-- 
"Tautologizm to coś tautologicznego"
   Maciej Katafiasz <mnews2 at wp.pl>
       http://mathrick.blog.pl