[gst-devel] Changing width/height properties from within plugin

[Karol]

On Fri, 26 Feb 2010 10:04:03 +0200, Stefan Kost wrote:

> Am 24.02.2010 18:09, schrieb Karol:
>> Hello,
>> 
>> I'm trying to write trivial plugin that does image rotation (90, 180,
>> etc. degrees).  My question is - where should I change "width" and
>> "height" properties?  I thought the proper place would be _chain()
>> function(*) where I deal with buffer contents.  However, pipeline dies
>> with internal error if I do that.  I guess I should handle that
>> mysterious beast called caps negotiation? (specifically: _set_caps()
>> function?)
> 
> If you can't use videflip, you can at least look how it is done there.

Well, yes.  I've looked at it already and implemented _transform_caps() 
in similar fashion.  However, why I needed to explicitly set "width" and 
"height" for caps when I wasn't any doing rotation/transformation is 
still puzzling to me.

While I don't understand why it happens that way - it does work.

Thanks.