[gst-devel] Fading images

[Greg Franklin]

I'm trying to write an application that will fade an image to black in a
smooth and controllable way.

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.

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