Called when a new preroll sample is available. This callback is called from the streaming thread. The new preroll sample can be retrieved with gstapp.app_sink.AppSink.pullPreroll either from this callback or from any other thread.
Called when a new preroll sample is available. This callback is called from the streaming thread. The new preroll sample can be retrieved with gstapp.app_sink.AppSink.pullPreroll either from this callback or from any other thread.