GStreamer 1.2.1, vs2013, cinder 0.8.5 and a 'hello world'

[Lasse Laursen]

Hey,

I've posted a bit previously about intentions of using GStreamer for 
streaming some video to an OpenGL texture. It resulted in a drawn out 
period of development where I spent about 2-3 weeks scrambling trying to 
recompile this and that and using all sorts of tools. Sufficed to say - 
it's taking me too long to figure out how to do that, so I'm forced to 
try a much, much simpler approach, just to get something simple working.

Essentially I'm just content with getting a set of raw frames out of a 
video using gstreamer and putting these in memory for my own use. I know 
that can easily ballon to several hundred megs, but I'm content with 
restricting myself to smaller film clips.

So I grabbed the latest releases of gstreamer 1.2.1 and got to work 
compiling the following simple 'hello world' example:

void VideoMaster::gstTesting3()
{
     GstElement *pipeline;
     GstBus *bus;
     GstMessage *msg;

     /* Initialize GStreamer */
     gst_init( NULL, NULL );

     /* Build the pipeline */
     pipeline = gst_parse_launch("playbin 
uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm", NULL);

     /* Start playing */
     gst_element_set_state(pipeline, GST_STATE_PLAYING);

     /* Wait until error or EOS */
     bus = gst_element_get_bus(pipeline);
     msg = gst_bus_timed_pop_filtered(bus, GST_CLOCK_TIME_NONE, 
(GstMessageType) (GST_MESSAGE_ERROR | GST_MESSAGE_EOS));

     /* Free resources */
     if (msg != NULL)
         gst_message_unref(msg);
     gst_object_unref(bus);
     gst_element_set_state(pipeline, GST_STATE_NULL);
     gst_object_unref(pipeline);

     //return 0;
}

So - if I run the command 'playbin 
uri=http://docs.gstreamer.com/media/sintel_trailer-480p.webm' straight 
from the command line gst-launch-1.0.exe, then things work out fine more 
or less. However, in my cinder application I get a big fat nothing.

I'm assuming this may have something to do with the fact that Cinder 
creates its own personal OpenGL rendering context and this simple 'hello 
world' example tries to create it's own rendering window which somehow 
creates trouble?

I am a bit puzzled though as the pipeline object itself just becomes a 
NULL object. Perhaps that's normal behavior if something goes wrong?

While I'm on a roll here - I was also wondering if someone could point 
me in the direction of what I should be looking at if I'm interested in 
letting the program open any video file gStreamer can handle, and 
putting them into a sink that allows me to extract raw single frame data?

Regards,
Gazoo