A container for features loaded from a shared object module. More...

#include <gstreamermm/plugin.h>

Inheritance diagram for Gst::Plugin:

Public Types
typedef sigc::slot< bool, const Glib::RefPtr< Gst::Plugin >&>	SlotInit
	For example, bool on_plugin_init(const Glib::RefPtr<Gst::Plugin>& plugin);. More...

typedef sigc::slot< bool, const Glib::RefPtr< Gst::Plugin >&>	SlotFilter
	For example, bool on_plugin_filter(const Glib::RefPtr<Gst::Plugin>& plugin);. More...

Public Member Functions
	Plugin (Plugin&& src) noexcept

Plugin&	operator= (Plugin&& src) noexcept

	~Plugin () noexcept override

GstPlugin*	gobj ()
	Provides access to the underlying C GObject. More...

const GstPlugin*	gobj () const
	Provides access to the underlying C GObject. More...

GstPlugin*	gobj_copy ()
	Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs. More...

Glib::ustring	get_name () const
	Get the short name of the plugin. More...

Glib::ustring	get_description () const
	Get the long descriptive name of the plugin. More...

Glib::ustring	get_filename () const
	get the filename of the plugin More...

Glib::ustring	get_license () const
	get the license of the plugin More...

Glib::ustring	get_package () const
	get the package the plugin belongs to. More...

Glib::ustring	get_origin () const
	get the URL where the plugin comes from More...

Glib::ustring	get_source () const
	get the source module the plugin belongs to. More...

Glib::ustring	get_version () const
	get the version of the plugin More...

Glib::ustring	get_release_date_string () const
	Get the release date (and possibly time) in form of a string, if available. More...

bool	is_loaded () const
	queries if the plugin is loaded into memory More...

Gst::Structure	get_cache_data () const
	Gets the plugin specific data cache. More...

void	set_cache_data (Gst::Structure& cache_data)
	Adds plugin specific data to cache. More...

Glib::RefPtr< Gst::Plugin >	load ()
	Loads plugin. More...

void	add_dependency (const Glib::StringArrayHandle& env_vars, const Glib::StringArrayHandle& paths, const Glib::StringArrayHandle& names, Gst::PluginDependencyFlags flags)
	Make GStreamer aware of external dependencies which affect the feature set of this plugin (ie. More...

void	add_dependency (const Glib::ustring& env_vars, const Glib::ustring& paths, const Glib::ustring& names, Gst::PluginDependencyFlags flags)
	Make GStreamer aware of external dependencies which affect the feature set of this plugin (ie. More...

Public Member Functions inherited from Gst::Object
	Object (Object&& src) noexcept

Object&	operator= (Object&& src) noexcept

	~Object () noexcept override

GstObject*	gobj ()
	Provides access to the underlying C GObject. More...

const GstObject*	gobj () const
	Provides access to the underlying C GObject. More...

GstObject*	gobj_copy ()
	Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs. More...

bool	is_element () const

bool	is_element_factory () const

bool	is_pad () const

bool	is_pad_template () const

bool	is_bin () const

guint32	get_flags () const
	Returns the entire set of flags for the object. More...

bool	set_name (const Glib::ustring& name)
	Sets the name of object, or gives object a guaranteed unique name (if name is `nullptr`). More...

Glib::ustring	get_name () const
	Returns a copy of the name of object. More...

bool	set_parent (const Glib::RefPtr< Gst::Object >& parent)
	Sets the parent of object to parent. More...

Glib::RefPtr< Gst::Object >	get_parent ()
	Returns the parent of object. More...

Glib::RefPtr< const Gst::Object >	get_parent () const
	Returns the parent of object. More...

void	unparent ()
	Clear the parent of object, removing the associated reference. More...

void	set_control_rate (Gst::ClockTime control_rate)
	Change the control-rate for this object. More...

Gst::ClockTime	get_control_rate () const
	Obtain the control-rate for this object. More...

Gst::ClockTime	suggest_next_sync () const
	Returns a suggestion for timestamps where buffers should be split to get best controller results. More...

bool	sync_values (Gst::ClockTime timestamp)
	Sets the properties of the object, according to the Gst::ControlSources that (maybe) handle them and for the given timestamp. More...

void	set_control_bindings_disabled (bool disabled)
	This function is used to disable all controlled properties of the object for some time, i.e. sync_values() will do nothing. More...

bool	has_asctive_control_bindings () const
	Check if the object has an active controlled properties. More...

bool	has_ancestor (const Glib::RefPtr< const Gst::Object >& ancestor) const
	Check if object has an ancestor ancestor somewhere up in the hierarchy. More...

bool	has_as_ancestor (const Glib::RefPtr< Gst::Object >& ancestor) const
	Check if object has an ancestor ancestor somewhere up in the hierarchy. More...

bool	has_as_parent (const Glib::RefPtr< Gst::Object >& parent) const
	Check if parent is the parent of object. More...

Glib::ustring	get_path_string ()
	Generates a string describing the path of object in the object hierarchy. More...

Glib::PropertyProxy< Glib::ustring >	property_name ()
	The name of the object. More...

Glib::PropertyProxy_ReadOnly< Glib::ustring >	property_name () const
	The name of the object. More...

Glib::PropertyProxy< Glib::RefPtr< Gst::Object > >	property_parent ()
	The parent of the object. More...

Glib::PropertyProxy_ReadOnly< Glib::RefPtr< Gst::Object > >	property_parent () const
	The parent of the object. More...

Glib::SignalProxy< void, const Glib::RefPtr< Gst::Object >&, GParamSpec*>	signal_deep_notify ()

int	get_refcount () const

Static Public Member Functions
static GType	get_type ()
	Get the GType for this class, for use with the underlying GObject type system. More...

static Glib::QueryQuark	error_quark ()
	Get the error quark. More...

static Glib::RefPtr< Gst::Plugin >	load_file (const Glib::ustring& filename)

static Glib::RefPtr< Gst::Plugin >	load_by_name (const Glib::ustring& name)
	Load the named plugin. More...

static bool	register_static (int major_version, int minor_version, const Glib::ustring& name, const Glib::ustring& description, const SlotInit& init_slot, const Glib::ustring&version, const Glib::ustring& license, const Glib::ustring& source, const Glib::ustring& package, const Glib::ustring& origin)

Static Public Member Functions inherited from Gst::Object
static GType	get_type ()
	Get the GType for this class, for use with the underlying GObject type system. More...

static bool	check_uniqueness (const Glib::ListHandle< const Gst::Object >& list, const Glib::ustring& name)
	Checks to see if there is any object named name in list. More...

Related Functions
(Note that these are not member functions.)
Glib::RefPtr< Gst::Plugin >	wrap (GstPlugin* object, bool take_copy=false)
	A Glib::wrap() method for this object. More...

Related Functions inherited from Gst::Object
Glib::RefPtr< Gst::Object >	wrap (GstObject* object, bool take_copy=false)
	A Glib::wrap() method for this object. More...

Additional Inherited Members
Protected Member Functions inherited from Gst::Object
virtual void	on_deep_notify (const Glib::RefPtr< Gst::Object >& prop_object, GParamSpec* prop)
	This is a default handler for the signal signal_deep_notify(). More...

Detailed Description

A container for features loaded from a shared object module.

GStreamer is extensible, so Gst::Element instances can be loaded at runtime. A plugin system can provide one or more of the basic GStreamer Gst::PluginFeature subclasses.

A plugin should export a symbol gst_plugin_desc that is a struct of type PluginDesc. the plugin loader will check the version of the core library the plugin was linked against and will create a new Gst::Plugin. It will then call the PluginInitFunc function that was provided in the gst_plugin_desc.

Once you have a handle to a Gst::Plugin (e.g. from the RegistryPool), you can add any object that subclasses Gst::PluginFeature.

Usually plugins are always automaticlly loaded so you don't need to call gst_plugin_load() explicitly to bring it into memory. There are options to statically link plugins to an app or even use GStreamer without a plugin repository in which case load() can be needed to bring the plugin into memory.

Last reviewed on 2016-06-06 (1.8.0)

Member Typedef Documentation

◆ SlotFilter

typedef sigc::slot< bool, const Glib::RefPtr<Gst::Plugin>& > Gst::Plugin::SlotFilter

For example, bool on_plugin_filter(const Glib::RefPtr<Gst::Plugin>& plugin);.

The filter function should return true if plugin is a match, false otherwise.

◆ SlotInit

typedef sigc::slot< bool, const Glib::RefPtr<Gst::Plugin>& > Gst::Plugin::SlotInit

For example, bool on_plugin_init(const Glib::RefPtr<Gst::Plugin>& plugin);.

The init function should return true if plugin was initialized successfully, false otherwise.

Constructor & Destructor Documentation

◆ Plugin()

Gst::Plugin::Plugin ( Plugin&& src )

noexcept

◆ ~Plugin()

Gst::Plugin::~Plugin ( )

overridenoexcept

Member Function Documentation

◆ add_dependency() [1/2]

void Gst::Plugin::add_dependency	(	const Glib::StringArrayHandle &	env_vars,
		const Glib::StringArrayHandle &	paths,
		const Glib::StringArrayHandle &	names,
		Gst::PluginDependencyFlags	flags
	)

Make GStreamer aware of external dependencies which affect the feature set of this plugin (ie.

the elements or typefinders associated with it).

GStreamer will re-inspect plugins with external dependencies whenever any of the external dependencies change. This is useful for plugins which wrap other plugin systems, e.g. a plugin which wraps a plugin-based visualisation library and makes visualisations available as GStreamer elements, or a codec loader which exposes elements and/or caps dependent on what external codec libraries are currently installed.

Parameters

env_vars	`nullptr`-terminated array of environment variables affecting the feature set of the plugin (e.g. an environment variable containing paths where to look for additional modules/plugins of a library), or `nullptr`. Environment variable names may be followed by a path component which will be added to the content of the environment variable, e.g. "HOME/.mystuff/plugins".
paths	`nullptr`-terminated array of directories/paths where dependent files may be, or `nullptr`.
names	`nullptr`-terminated array of file names (or file name suffixes, depending on flags) to be used in combination with the paths from paths and/or the paths extracted from the environment variables in env_vars, or `nullptr`.
flags	Optional flags, or Gst::PLUGIN_DEPENDENCY_FLAG_NONE.

◆ add_dependency() [2/2]

void Gst::Plugin::add_dependency	(	const Glib::ustring &	env_vars,
		const Glib::ustring &	paths,
		const Glib::ustring &	names,
		Gst::PluginDependencyFlags	flags
	)

Make GStreamer aware of external dependencies which affect the feature set of this plugin (ie.

the elements or typefinders associated with it).

GStreamer will re-inspect plugins with external dependencies whenever any of the external dependencies change. This is useful for plugins which wrap other plugin systems, e.g. a plugin which wraps a plugin-based visualisation library and makes visualisations available as GStreamer elements, or a codec loader which exposes elements and/or caps dependent on what external codec libraries are currently installed.

Convenience wrapper function for add_dependency() which takes simple strings as arguments instead of string arrays, with multiple arguments separated by predefined delimiters (see above).

Parameters

env_vars	One or more environment variables (separated by ':', ';' or ','), or `nullptr`. Environment variable names may be followed by a path component which will be added to the content of the environment variable, e.g. "HOME/.mystuff/plugins:MYSTUFF_PLUGINS_PATH".
paths	One ore more directory paths (separated by ':' or ';' or ','), or `nullptr`. Example: "/usr/lib/mystuff/plugins".
names	One or more file names or file name suffixes (separated by commas), or `nullptr`.
flags	Optional flags, or Gst::PLUGIN_DEPENDENCY_FLAG_NONE.

◆ error_quark()

static Glib::QueryQuark Gst::Plugin::error_quark ( )

static

Get the error quark.

Returns: The error quark used in GError messages.

◆ get_cache_data()

Gst::Structure Gst::Plugin::get_cache_data ( ) const

Gets the plugin specific data cache.

If it is nullptr there is no cached data stored. This is the case when the registry is getting rebuilt.

Returns: The cached data as a Gst::Structure or nullptr.

◆ get_description()

Glib::ustring Gst::Plugin::get_description ( ) const

Get the long descriptive name of the plugin.

Returns: The long name of the plugin.

◆ get_filename()

Glib::ustring Gst::Plugin::get_filename ( ) const

get the filename of the plugin

Returns: The filename of the plugin.

◆ get_license()

Glib::ustring Gst::Plugin::get_license ( ) const

get the license of the plugin

Returns: The license of the plugin.

◆ get_name()

Glib::ustring Gst::Plugin::get_name ( ) const

Get the short name of the plugin.

Returns: The name of the plugin.

◆ get_origin()

Glib::ustring Gst::Plugin::get_origin ( ) const

get the URL where the plugin comes from

Returns: The origin of the plugin.

◆ get_package()

Glib::ustring Gst::Plugin::get_package ( ) const

get the package the plugin belongs to.

Returns: The package of the plugin.

◆ get_release_date_string()

Glib::ustring Gst::Plugin::get_release_date_string ( ) const

Get the release date (and possibly time) in form of a string, if available.

For normal GStreamer plugin releases this will usually just be a date in the form of "YYYY-MM-DD", while pre-releases and builds from git may contain a time component after the date as well, in which case the string will be formatted like "YYYY-MM-DDTHH:MMZ" (e.g. "2012-04-30T09:30Z").

There may be plugins that do not have a valid release date set on them.

Returns: The date string of the plugin, or nullptr if not available.

◆ get_source()

Glib::ustring Gst::Plugin::get_source ( ) const

get the source module the plugin belongs to.

Returns: The source of the plugin.

◆ get_type()

static GType Gst::Plugin::get_type ( )

static

Get the GType for this class, for use with the underlying GObject type system.

◆ get_version()

Glib::ustring Gst::Plugin::get_version ( ) const

get the version of the plugin

Returns: The version of the plugin.

◆ gobj() [1/2]

GstPlugin* Gst::Plugin::gobj ( )

inline

Provides access to the underlying C GObject.

◆ gobj() [2/2]

const GstPlugin* Gst::Plugin::gobj ( ) const

inline

Provides access to the underlying C GObject.

◆ gobj_copy()

GstPlugin* Gst::Plugin::gobj_copy ( )

Provides access to the underlying C instance. The caller is responsible for unrefing it. Use when directly setting fields in structs.

◆ is_loaded()

bool Gst::Plugin::is_loaded ( ) const

queries if the plugin is loaded into memory

Returns: true is loaded, false otherwise.

◆ load()

Glib::RefPtr<Gst::Plugin> Gst::Plugin::load ( )

Loads plugin.

Note that the return value is the loaded plugin; plugin is untouched. The normal use pattern of this function goes like this:

GstPlugin *loaded_plugin; loaded_plugin = gst_plugin_load (plugin); // presumably, we're no longer interested in the potentially-unloaded plugin gst_object_unref (plugin); plugin = loaded_plugin;

Returns: A reference to a loaded plugin, or nullptr on error.

◆ load_by_name()

static Glib::RefPtr<Gst::Plugin> Gst::Plugin::load_by_name ( const Glib::ustring & name )

static

Load the named plugin.

Refs the plugin.

Parameters

name	Name of plugin to load.

Returns: A reference to a loaded plugin, or nullptr on error.

◆ load_file()

static Glib::RefPtr<Gst::Plugin> Gst::Plugin::load_file ( const Glib::ustring & filename )

static

Exceptions

Gst::PluginError.

◆ operator=()

Plugin& Gst::Plugin::operator= ( Plugin&& src )

noexcept

◆ register_static()

static bool Gst::Plugin::register_static	(	int	major_version,
		int	minor_version,
		const Glib::ustring &	name,
		const Glib::ustring &	description,
		const SlotInit&	init_slot,
		const Glib::ustring &	version,
		const Glib::ustring &	license,
		const Glib::ustring &	source,
		const Glib::ustring &	package,
		const Glib::ustring &	origin
	)

static

◆ set_cache_data()

void Gst::Plugin::set_cache_data ( Gst::Structure& cache_data )

Adds plugin specific data to cache.

Passes the ownership of the structure to the plugin.

The cache is flushed every time the registry is rebuilt.

Parameters

cache_data A structure containing the data to cache.

Friends And Related Function Documentation

◆ wrap()

Glib::RefPtr< Gst::Plugin > wrap	(	GstPlugin *	object,
		bool	take_copy = `false`
	)

Parameters

object	The C instance.
take_copy	False if the result should take ownership of the C instance. True if it should take a new copy or ref.

Returns: A C++ instance that wraps this C instance.

Public Types

Public Member Functions

Static Public Member Functions

Related Functions

Additional Inherited Members

Detailed Description

Member Typedef Documentation

◆ SlotFilter

◆ SlotInit

Constructor & Destructor Documentation

◆ Plugin()

◆ ~Plugin()

Member Function Documentation

◆ add_dependency() [1/2]

◆ add_dependency() [2/2]

◆ error_quark()

◆ get_cache_data()

◆ get_description()

◆ get_filename()

◆ get_license()

◆ get_name()

◆ get_origin()

◆ get_package()

◆ get_release_date_string()

◆ get_source()

◆ get_type()

◆ get_version()

◆ gobj() [1/2]

◆ gobj() [2/2]

◆ gobj_copy()

◆ is_loaded()

◆ load()

◆ load_by_name()

◆ load_file()

◆ operator=()

◆ register_static()

◆ set_cache_data()

Friends And Related Function Documentation

◆ wrap()