basics/element_factory.cc

A gstreamermm Gst::ElementFactory example.

/*
 * This example presents how to use Gst::ElementFactory class, getting
 * information and create specific element.
 */
#include <gstreamermm.h>

#include <iostream>

int main(int argc, char *argv[])
{
  Gst::init(argc, argv);

  // Get list of all primary demuxers in the system
  std::cout << "List of primary demuxers: " << std::endl;
  for (Glib::RefPtr<Gst::ElementFactory> factory
        : Gst::ElementFactory::get_elements(Gst::ELEMENT_FACTORY_TYPE_DEMUXER, Gst::RANK_PRIMARY))
  {
    std::cout << " * " << factory->get_name() << std::endl;
  }
  std::cout << std::endl;

  Glib::RefPtr<Gst::ElementFactory> fakesrc_factory = Gst::ElementFactory::find("fakesrc");
  if (!fakesrc_factory)
  {
    std::cerr << "Failed to find factory of type 'fakesrc'" << std::endl;
    return -1;
  }

  // Read information about an author of the element
  std::cout << "Author of the element '" << fakesrc_factory->get_name() << "' is "
      << fakesrc_factory->get_metadata(GST_ELEMENT_METADATA_AUTHOR) << std::endl << std::endl;

  // Read all available information about the element
  std::cout << "All information about element '" << fakesrc_factory->get_name() << "':" << std::endl;
  for (auto metadata_key : fakesrc_factory->get_metadata_keys())
  {
    std::cout << " * " << metadata_key << ": " << fakesrc_factory->get_metadata(metadata_key) << std::endl;
  }


  // Create element fakesrc

  // Method 1
  {
    Glib::RefPtr<Gst::Element> fakesrc = fakesrc_factory->create("source");

    if (!fakesrc)
    {
      std::cerr << "Failed to create element of type 'fakesrc'" << std::endl;
      return -1;
    }
  }

  // Method 2
  {
    Glib::RefPtr<Gst::Element> fakesrc = Gst::ElementFactory::create_element("fakesrc", "source");
    if (!fakesrc)
    {
      std::cerr << "Failed to create element of type 'fakesrc'" << std::endl;
      return -1;
    }
  }

  return 0;
}