gstreamer pipeline states

[Mayank Agarwal]

Hi,


I have gstreamer plugin by the name firstplugin:

gst_firstplugin_init{

}
gst_firstplugin_base_init
{



}
gst_firstplugin_class_init
{


gobject_class->set_property = gst_firstplugin_set_property;
gobject_class->get_property = gst_firstplugin_get_property;
gobject_class->finalize = gst_firstplugin_finalize;


and  functons like:
gstelement_class->change_state = gst_qamtunersrc_change_state;
gstbasesrc_class->start = gst_firstplugin_start;
gstbasesrc_class->stop = gst_firstplugin_stop;


}




I am getting logs to the function set property but
gstreamer pipeline is not starting.I want to ask when does the gst
plugin pipeline state changes
1.GST_STATE_CHANGE_NULL_TO_READY
2.GST_STATE_CHANGE_READY_TO_PAUSED
3.GST_STATE_CHANGE_PAUSED_TO_PLAYING

how the gstreamer pipeline changes state internally.
Is there anyway to debug the internal state of the pipeline.
if the pipeline is not starting what can be the reasons for that.
when does the function pointer functions in class_init gets
executed.

Regards,
Mayank