Re: [Vala] Problem with gstreamer bin

["Thijs Vermeir" <thijsvermeir gmail com>]

Hi,

2008/11/14 Spencer, Matthew <MSpencer nds com>:
> Hi Guys
>
> I am playing with Vala with a view to presenting information about it at our
> companies developer conference in a couple of weeks.  With this in mind I am
> trying to build up a test application that shows video playback using
> GStreamer.  I am having problems with the following code:
>
> private Element createVideoBin() {
>   var bin=new Bin("videobin");
>   var queue=ElementFactory.make("queue","queue");
>   var sink=ElementFactory.make("autovideosink","videosink");
>   var ghostPad=new GhostPad("sink",queue.get_pad("sink"));
>   bin.add_many(queue,sink);
>   queue.link(sink);
>   bin.add_pad(ghost);
>   return(bin);
> }

bin.add_many is the problem because the c function takes the
ownership, but the bindings don't do it. Just use bin.add for every
element as a workaround...

Gr,
Thijs

> When attempting to use the returned bin, I get a segfault.  This is because
> (I think, on examining the generated C code) the elements are being unrefd
> before the bin is returned.  I am sure this is not supposed to happen.
>
> I get a number of error messaged when running the app:
> (mystreamer:16361): GStreamer-CRITICAL **:
> Trying to dispose of object "videosink", but it still has a parent
> "videobin".
> You need to let the parent manage the object instead of unreffing the object
> directly.
>
> I am assuming this is because I need to inform the code that I wish to
> transfer ownership of the objects to the 'Bin', but how do I do this, and is
> there a way that this can be picked up by the compiler to prevent this type
> of problem?
>
> Cheers
>
> Matt
> *********************************************************************************************************
> This e-mail is confidential, the property of NDS Ltd and intended for the
> addressee only. Any dissemination, copying or distribution of this message
> or any attachments by anyone other than the intended recipient is strictly
> prohibited. If you have received this message in error, please immediately
> notify the postmaster nds com and destroy the original message. Messages
> sent to and from NDS may be monitored. NDS cannot guarantee any message
> delivery method is secure or error-free. Information could be intercepted,
> corrupted, lost, destroyed, arrive late or incomplete, or contain viruses.
> We do not accept responsibility for any errors or omissions in this message
> and/or attachment that arise as a result of transmission. You should carry
> out your own virus checks before opening any attachment. Any views or
> opinions presented are solely those of the author and do not necessarily
> represent those of NDS.
>
> To protect the environment please do not print this e-mail unless necessary.
>
> NDS Limited Registered office: One Heathrow Boulevard, 286 Bath Road, West
> Drayton, Middlesex, UB7 0DQ, United Kingdom. A company registered in England
> and Wales Registered no. 3080780 VAT no. GB 603 8808 40-00
> **********************************************************************************************************
>
> _______________________________________________
> Vala-list mailing list
> Vala-list gnome org
> http://mail.gnome.org/mailman/listinfo/vala-list