video compositor hangs when no data pushing to appsrc

Tim Müller tim at
Wed May 22 08:01:57 UTC 2019

On Wed, 2019-05-22 at 02:45 -0500, longkas wrote:


> I want to mix two video streams together using compositor element, 
> first I add one stream in to the pipeline:
>    videotestsrc pattern=ball ! compositor name=mix ! autovideosink
> Then I build an appsrc with push mode and add it :
>     appsrc ! mix.
> Then the video hangs there if I do not push data, how to avoid the
> hang, I want the compositor to continue works whether or not my
> appsrc push data, please help, thank you

If you make one of your inputs live (e.g. videotestsrc is-live=true)
compositor will work in live mode and will produce data even if you
don't push anything into your appsrc. You might also want to set the
latency property on compositor then to tell it how long it should wait.


Tim Müller, Centricular Ltd -

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