Generic error of GStreamer

[Tim-Philipp Müller]

On Sun, 2013-06-09 at 15:37 +0200, Marco Trapanese wrote:
> Il 09/06/2013 12:57, Tim-Philipp Müller ha scritto:
> > decodebin2 has dynamic pads which will only be created after you start 
> > up the pipeline. gst-launch handles this magically under the hood. I 
> > suspect this call: decoder->link(colorspace); fails. Anyway, just use 
> > playbin2 - much easier (create it, set the "uri" property, set it to 
> > playing state). Cheers -Tim 
> 
> 
> Hi, I know playbin2 and it works, indeed.
> I'm trying to avoid to use it because I'll need to add a " videobalance 
> saturation=0.0" in the pipeline and I don't know how to do that with 
> playbin2.

You can do that by creating a GstBin, adding a videobalance to it, and
your videosink (with both linked together). Then you create a "ghost
pad" that has videobalance's sink pad as "target". Then you add that
ghost pad to the GstBin, and then you can set that bin as video-sink on
playbin2. That's roughly what totem does as well.

In 1.0 playbin contains a colorbalance internally already, fwiw.

> Furthermore using filesrc allows me to change to another source easily 
> (e.g. v4l2src).

It's not that easy really, you'll have to shut down the pipeline before
changing the source.

> I read the docs but I cannot find indication how to achieve that.

"the docs" ? :)

http://gstreamer.freedesktop.org/data/doc/gstreamer/head/manual/html/chapter-pads.html

Cheers
 -Tim