Gstreamermm plugin initialization error

[Fernando Herrero Carrón <elferdo gmail com>]

Hello everyone,

I am beginning to play with gstreamermm (and gstreamer in general, for
that matter) eventhough I have been using gtk-- for a long time.

I'm using gstreamermm on FreeBSD 8.2-STABLE with the system compiler:

g++ (GCC) 4.2.2 20070831 prerelease [FreeBSD]

Compiling and installing gstreamermm from ports was flawless, and I can
compile, link and run simple examples against it. However, some plugins
that work OK for C programs fail to load when using the C++ wrappers.

For example, running

$> gstreamer-properties --gst-debug-level=5

yields

[...]
GST_PLUGIN_LOADING gstpluginfeature.c:107:gst_plugin_feature_load: loading plugin for feature 0x8067007e0; 'fakesink'
GST_PLUGIN_LOADING gstpluginfeature.c:111:gst_plugin_feature_load: loading plugin coreelements
GST_PLUGIN_LOADING gstplugin.c:1293:gst_plugin_load_by_name: looking up plugin coreelements in default registry
GST_PLUGIN_LOADING gstplugin.c:1296:gst_plugin_load_by_name: loading plugin coreelements from file /usr/local/lib/gstreamer-0.10/libgstcoreelements.so
GST_PLUGIN_LOADING gstplugin.c:737:gst_plugin_load_file: attempt to load plugin "/usr/local/lib/gstreamer-0.10/libgstcoreelements.so"
GST_PLUGIN_LOADING gstplugin.c:834:gst_plugin_load_file: Plugin 0x806767150 for file "/usr/local/lib/gstreamer-0.10/libgstcoreelements.so" prepared, calling entry function...
GST_PLUGIN_LOADING gstplugin.c:841:gst_plugin_load_file: Plugin 0x806767150 for file "/usr/local/lib/gstreamer-0.10/libgstcoreelements.so" prepared, registering...
GST_PLUGIN_LOADING gstplugin.c:540:gst_plugin_register_func: plugin "/usr/local/lib/gstreamer-0.10/libgstcoreelements.so" looks good
GST_ELEMENT_FACTORY gstelementfactory.c:232:gst_element_register:<registry0> update existing feature 0x8067005a0 (capsfilter)
GST_ELEMENT_FACTORY gstelementfactory.c:232:gst_element_register:<registry0> update existing feature 0x8067006c0 (fakesrc)
GST_ELEMENT_FACTORY gstelementfactory.c:232:gst_element_register:<registry0> update existing feature 0x8067007e0 (fakesink)
[...]

This looks like once a plugin gets loaded, all its features get registered.

Now I compile the following program:

#include <gstreamermm.h>

int main(int argc, char **argv) {
	// Initialize Gstreamermm:
	Gst::init(argc, argv);

	// Create elements:
	Glib::RefPtr<Gst::Element> fakesrc = Gst::ElementFactory::create_element("fakesrc");

	if(fakesrc == Glib::RefPtr<Gst::Element>(NULL))
		throw -1;

	return 0;
}

And if I run it with --gst-debug-level=5 I get the following errors:

[...]
GST_PLUGIN_LOADING gstpluginfeature.c:111:gst_plugin_feature_load: loading plugin coreelements
GST_PLUGIN_LOADING gstplugin.c:1293:gst_plugin_load_by_name: looking up plugin coreelements in default registry
GST_PLUGIN_LOADING gstplugin.c:1296:gst_plugin_load_by_name: loading plugin coreelements from file /usr/local/lib/gstreamer-0.10/libgstcoreelements.so
GST_PLUGIN_LOADING gstpluginfeature.c:116:gst_plugin_feature_load: loaded plugin coreelements
GST_PLUGIN_LOADING gstpluginfeature.c:146:gst_plugin_feature_load: Tried to load plugin containing feature 'fakesrc', but feature was not found.

(mygstreamer:31703): GStreamer-CRITICAL **: gst_element_factory_get_element_type: assertion `GST_IS_ELEMENT_FACTORY (factory)' failed

(mygstreamer:31703): GLib-GObject-CRITICAL **: g_object_unref: assertion `G_IS_OBJECT (object)' failed

(mygstreamer:31703): GStreamer-CRITICAL **: gst_element_register: assertion `g_type_is_a (type, GST_TYPE_ELEMENT)' failed
GST_PLUGIN_LOADING gstplugin.c:559:gst_plugin_register_func: plugin "/usr/local/lib/gstreamer-0.10/libgstcoreelements.so" failed to initialise
GST_PLUGIN_LOADING gstplugin.c:846:gst_plugin_load_file: gst_plugin_register_func failed for plugin "/usr/local/lib/gstreamer-0.10/libgstcoreelements.so"
GST_PLUGIN_LOADING gstplugin.c:1301:gst_plugin_load_by_name: load_plugin error: File "/usr/local/lib/gstreamer-0.10/libgstcoreelements.so" appears to be a GStreamer plugin, but it failed to initialize
GST_PLUGIN_LOADING gstpluginfeature.c:133:gst_plugin_feature_load: Failed to load plugin containing feature 'capsfilter'.
[...]
GST_PLUGIN_LOADING gstpluginfeature.c:146:gst_plugin_feature_load: Tried to load plugin containing feature 'fakesrc', but feature was not found.
GST_ELEMENT_FACTORY gstelementfactory.c:409:gst_element_factory_create:<elementfactory3> loading plugin containing feature (null) returned NULL!
GST_ELEMENT_FACTORY gstelementfactory.c:470:gst_element_factory_make:<elementfactory3> couldn't create instance!
terminate called after throwing an instance of 'int'


Here it looks like it is trying to initialize a plugin that has been
already loaded, is that possible?

Any help with this will be appreciated.

Thank you very much,
Fernando