videocrop and videobox not working in video coordinate...

[Eric Trousset]

Yes, I understand that. Then, when using playbin, how can I get the original video size and to be able the add a capfilter in front of the videocrop element to avoid video scaling prior to the cropping?

> -----Original Message-----
> From: gstreamer-devel-bounces at lists.freedesktop.org [mailto:gstreamer-
> devel-bounces at lists.freedesktop.org] On Behalf Of Sebastian Dröge
> Sent: jeudi 23 janvier 2014 09:22
> To: Discussion of the development of and with GStreamer
> Subject: Re: videocrop and videobox not working in video coordinate...
> 
> On Mi, 2014-01-22 at 09:59 +0100, Eric Trousset wrote:
> > Hi,
> > It looks like videocrop and videobox tries to negotiate the caps based on
> the output, thus negotiating a input of output size + cropping offsets.
> > So if we have a 1920x1080 video that we want to render in a 320x200
> surface, the videoxxx element will negociate an input of
> 320+left+rightx200+top+bottom.
> > This doesn't really make sence IMO cause we want to crop a certain
> amount in the original video coordinate , so videoxxx should accept the full
> video size on input, crop it, and then we can do the videoscale to obtain the
> final video size.
> >
> > Actually this is an issue only when using playbin, giving a custom videosink
> bin that has the videobox/crop element.
> >
> > Is there a easy way to have the input negotiate the fullvideo size?
> 
> Well, that's how these elements work. They add or remove X pixels to/from
> every border. Thus the output will be the same size as the input with these
> changes. Which on the other hand means that if downstream can only accept
> a single size, then the input will have to be that size with the inverse changes
> of the videocrop/box element.
> 
> You'll have to put a videoscale somewhere for example if you want to scale
> the video before or after cropping.
> 
> --
> Sebastian Dröge, Centricular Ltd - http://www.centricular.com Expertise,
> Straight from the Source