[gst-devel] Fading images

[Stefan Kost]

Hi Greg,

Greg Franklin wrote:
> I'm trying to write an application that will fade an image to black in a
> smooth and controllable way.
>
>   
Check out the GstController stuff.
> I'm using the videobalance plugin to do the fade but I'm unable to control
> the brightness while the image is playing.  All I've been able to do is
> create new pipelines each with gradually decreasing brightness and output
> them to the same display.
> This works except that the fade isn't smooth.  The problem is getting the
> pipelines to display in sequence.  Because of the amount of time it takes
> to get the pipeline into the playing state I have to create them all at
> the same time, however there is no guarantee which order the pipelines
> will display in.
>   
Ouch, I am afraid you have to add Controller support to the videobalance
element first. Fortunately that is very easy and well documented (I
hope) in the API docs.
> I have tried changing the state of the pipeline/videobalance element to
> paused or ready to change the brightness but various attempts at this have
> either resulted in the image disappearing or the new brightness doesn't
> get applied to the image.
>
> Is there a way to either control the brightness of the image whilst it is
> displaying or get the pipelines to run in order without introducing any
> delay.  The first option would be the prefered method.
>
> Many thanks
>
> Greg Franklin
>   
Stefan