Re: ClutterGst plans

[Lionel Landwerlin <llandwerlin gmail com>]

On 05/02/13 02:24, Rob Kramer wrote:
> Hi Lionel,
>
> On 02/04/2013 08:17 PM, Lionel Landwerlin wrote:
> > So I think the most important change would be to detach what is 
> > playing the video from what displays the video. In recent patches 
> > from Collabora [1], a ClutterGstActor class has been introduced. I 
> > think it would be cool if we could use this class as a point of 
> > display for a media pipeline. Basically this class/interface would 
> > just be charge of drawing images on the screen. And the way we set 
> > what it's going to be display, is by attaching a player element to it.
>
> I'm interested in gapless playback as well, but my definition of 
> gapless is related to GST pre-rolling time. I basically have a set of 
> a few clips that need to be started at specific time intervals, but 
> the pre-rolling time is not deterministic and can take up to a second. 
> Could the player/actor split be used to keep a few idle pre-rolled 
> players lying around, which can be slotted into an actor and started 
> when needed?

Hi Rob,

I think you should be able to do that already, by using 2 
ClutterVideoTexture. Let say you have the first pipeline playing a 
stream. While it's playing, just prepare the second one, and put it to 
PAUSED state. By getting the GstPipeline from the ClutterVideoTexture, 
you can listen to the state of the pipeline. When it becomes READY, you 
should be able to start playing without preroll delay.

We don't really have such a mechanism in ClutterGst at the moment. And 
I'm not sure if we will at some point. But as explained above, that's a 
bit of logic you can easily implement into you application.

The changes we are going to make will pretty much keep things the same 
way. Except you won't need to have 2 ClutterVideoTexture (and the 2 
respective GstPipeline). You will just have a ClutterGstActor and 2 
ClutterGstPlayer, each of them having a GstPipeline on which you need to 
listen to the READY state in order to be sure the preroll has been done.

-
Lionel