"Uncrashable" video/audio source and sinks

[Tim Müller]

On Mon, 2014-01-20 at 05:19 -0800, superlou wrote:

> I apologize if this is a dumb question.  I've thrown around a video toaster
> like application for about a year now in my free time, where a requirement
> is to be able to add/remove/relocate bins without stopping the pipeline. 
> What I've found is that there is a huge world of edge cases to handle to
> block the pads, change the pipeline, and remove the blocks without the
> pipeline crashing.  Also, there are some elements (v4l2src) that crash
> themselves if they lose their source, and I haven't found a way to detect
> their loss of signals before the pipeline goes down.
> 
> I was wondering if there is a simpler way: is there some sort of generic
> video (and audio) sink element that generates black frames (or silent audio)
> of a predefined cap when it is not linked properly, and forwards the good
> data when it is linked properly?  Then I can create bins where all the
> inputs are linked first to this magic sink element so the worst case
> scenario is that I get black/silent output when the links are
> rearranged/broken.  Is there already some kind of functionality like this,
> or would it be possible to implement?  I'm not particularly concerned about
> performance since this is an application where I can throw a lot of the
> hardware at the problem.  Feel free to tell me off if I'm trying to abstract
> something in an inappropriate way.
> 
> Open to any suggestions, criticisms, etc.

Have a look at e.g. intervideosink/intervideosrc , maybe those are along
the lines of what you're looking for.

Cheers
 -Tim

-- 
Tim Müller, Centricular Ltd - http://www.centricular.com