GStreamer plugin with GStreamermm(C++)

Question

I'm trying to write a gstreamer plugin in C++, using the GStreamermm bindings. Now, there's a good plugins writers guide (http://gstreamer.freedesktop.org/data/doc/gstreamer/head/pwg/html/), and on the web there's various examples and templates, but for gstreamermm, there's very little amount of documentation whatsoever.

I know I could just resort to using a mixture of C and C++, but using the C++ bindings seems so much more elegant.

Simply 'translating' the examples found in the gstreamer pwg to gstreamermm is kind of a dead end; gstreamer requires the use of quite a few macros for defining types, which I cannot see an immediate gstreamermm translation to. Additionally, I have only little experience with gstreamer, and absolutely no experience with gobj (so far).

Is anyone able to put me on the right track? Even the tiniest example or explanation would do.

Thanks

Answer 1

I've asked this on the gtkmm mailing list a couple of days ago, and got the following answer (from José Alburquerque):

Presently, the only plug-ins that have a (probably non-existent) possibility of being developed using gstreamermm are ones that are private to applications. If that's possible, These plug-ins would be registered using the Gst::Plugin::register_static()[1] method and not the process that you've described above.

[1] http://developer.gnome.org/gstreamermm/unstable/classGst_1_1Plugin.html#ac0728bb285ae1bed9298c0f9ea522ad9

In theory, one would extend one of the gstreamermm base classes[2] and call the Gst::ElementFactory::register_element()[3] method in the Gst::Plugin::SlotInit slot (callback) so that an element factory that generates these elements can be created. That factory can then be added to the registry using Gst::Registry::add_feature()[4] in the same Gst::Plugin::SlotInit slot.

[2] http://developer.gnome.org/gstreamermm/unstable/group__GstBaseClasses.html

[3] The Gst::ElementFactory::register_element() method is a method that is not implemented yet but would wrap the gst_element_register() function. That would be part of an upcoming release.

[4] http://developer.gnome.org/gstreamermm/unstable/classGst_1_1Registry.html#ae1f9a1ddd60ef5a7e1f8cddf14ec404f

I've not tested this and don't really know exactly how it would work (or if it actually would) but it's how I'd try if I had to. However, I think it's easier to write the plug-in in C presently, but that's just a matter of making things easier.