Initializing the gstreamer library

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int
main (int argc, char *argv[])
{
  // initialize the GStreamer library
  gst_init (&argc, &argv);
  ...
}

It's allowed to pass two NULL pointers to gst_init() in case you don't want to pass the command line args to GStreamer.

You can also use GOption to initialize your own parameters as shown in the next code fragment:

Initializing own parameters when initializing gstreamer

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static gboolean stats = FALSE;
...
int
main (int argc, char *argv[])
{
 GOptionEntry options[] = {
  {"tags", 't', 0, G_OPTION_ARG_NONE, &tags,
      N_("Output tags (also known as metadata)"), NULL},
  {NULL}
 };
 ctx = g_option_context_new ("[ADDITIONAL ARGUMENTS]");
 g_option_context_add_main_entries (ctx, options, GETTEXT_PACKAGE);
 g_option_context_add_group (ctx, gst_init_get_option_group ());
 if (!g_option_context_parse (ctx, &argc, &argv, &err)) {
   g_print ("Error initializing: %s\n", GST_STR_NULL (err->message));
   exit (1);
 }
 g_option_context_free (ctx);
...
}

Use gst_version() to query the library version at runtime or use the GST_VERSION_* macros to find the version at compile time. Optionally gst_version_string() returns a printable string.

The gst_deinit() call is used to clean up all internal resources used by GStreamer. It is mostly used in unit tests to check for leaks.

gst_init ()

void
gst_init (int *argc,
          char **argv[]);

Initializes the GStreamer library, setting up internal path lists, registering built-in elements, and loading standard plugins.

Unless the plugin registry is disabled at compile time, the registry will be loaded. By default this will also check if the registry cache needs to be updated and rescan all plugins if needed. See gst_update_registry() for details and section

for how to disable automatic registry updates.

WARNING: This function does not work in the same way as corresponding functions in other glib-style libraries, such as gtk_init(). In particular, unknown command line options cause this function to abort program execution.

gst_init_check ()

gboolean
gst_init_check (int *argc,
                char **argv[],
                GError **err);

Initializes the GStreamer library, setting up internal path lists, registering built-in elements, and loading standard plugins.

This function will return FALSE if GStreamer could not be initialized for some reason. If you want your program to fail fatally, use gst_init() instead.

gst_init_get_option_group ()

GOptionGroup *
gst_init_get_option_group (void);

Returns a GOptionGroup with GStreamer's argument specifications. The group is set up to use standard GOption callbacks, so when using this group in combination with GOption parsing methods, all argument parsing and initialization is automated.

This function is useful if you want to integrate GStreamer with other libraries that use GOption (see g_option_context_add_group() ).

If you use this function, you should make sure you initialise the GLib threading system as one of the very first things in your program (see the example at the beginning of this section).

[skip]

gst_is_initialized ()

gboolean
gst_is_initialized (void);

Use this function to check if GStreamer has been initialized with gst_init() or gst_init_check().

gst_deinit ()

void
gst_deinit (void);

Clean up any resources created by GStreamer in gst_init().

It is normally not needed to call this function in a normal application as the resources will automatically be freed when the program terminates. This function is therefore mostly used by testsuites and other memory profiling tools.

After this call GStreamer (including this method) should not be used anymore.

gst_version ()

void
gst_version (guint *major,
             guint *minor,
             guint *micro,
             guint *nano);

Gets the version number of the GStreamer library.

gst_version_string ()

gchar *
gst_version_string (void);

This function returns a string that is useful for describing this version of GStreamer to the outside world: user agent strings, logging, ...

gst_segtrap_is_enabled ()

gboolean
gst_segtrap_is_enabled (void);

Some functions in the GStreamer core might install a custom SIGSEGV handler to better catch and report errors to the application. Currently this feature is enabled by default when loading plugins.

Applications might want to disable this behaviour with the gst_segtrap_set_enabled() function. This is typically done if the application wants to install its own handler without GStreamer interfering.

gst_segtrap_set_enabled ()

void
gst_segtrap_set_enabled (gboolean enabled);

Applications might want to disable/enable the SIGSEGV handling of the GStreamer core. See gst_segtrap_is_enabled() for more information.

gst_registry_fork_is_enabled ()

gboolean
gst_registry_fork_is_enabled (void);

By default GStreamer will perform scanning and rebuilding of the registry file using a helper child process.

Applications might want to disable this behaviour with the gst_registry_fork_set_enabled() function, in which case new plugins are scanned (and loaded) into the application process.

gst_registry_fork_set_enabled ()

void
gst_registry_fork_set_enabled (gboolean enabled);

Applications might want to disable/enable spawning of a child helper process when rebuilding the registry. See gst_registry_fork_is_enabled() for more information.

gst_update_registry ()

gboolean
gst_update_registry (void);

Forces GStreamer to re-scan its plugin paths and update the default plugin registry.

Applications will almost never need to call this function, it is only useful if the application knows new plugins have been installed (or old ones removed) since the start of the application (or, to be precise, the first call to gst_init()) and the application wants to make use of any newly-installed plugins without restarting the application.

Applications should assume that the registry update is neither atomic nor thread-safe and should therefore not have any dynamic pipelines running (including the playbin and decodebin elements) and should also not create any elements or access the GStreamer registry while the update is in progress.

Note that this function may block for a significant amount of time.

gst_get_main_executable_path ()

const gchar *
gst_get_main_executable_path (void);

This helper is mostly helpful for plugins that need to inspect the folder of the main executable to determine their set of features.

When a plugin is initialized from the gst-plugin-scanner external process, the returned path will be the same as from the parent process.

Since: 1.14