GstElementFactory

GstElementFactory — Create GstElements from a factory

Synopsis


#include <gst/gst.h>


struct      GstElementFactory;
gboolean    gst_element_register            (GstPlugin *plugin,
                                             const gchar *name,
                                             guint rank,
                                             GType type);
GstElementFactory* gst_element_factory_find (const gchar *name);
GType       gst_element_factory_get_element_type
                                            (GstElementFactory *factory);
G_CONST_RETURN gchar* gst_element_factory_get_longname
                                            (GstElementFactory *factory);
G_CONST_RETURN gchar* gst_element_factory_get_klass
                                            (GstElementFactory *factory);
G_CONST_RETURN gchar* gst_element_factory_get_description
                                            (GstElementFactory *factory);
G_CONST_RETURN gchar* gst_element_factory_get_author
                                            (GstElementFactory *factory);
guint       gst_element_factory_get_num_pad_templates
                                            (GstElementFactory *factory);
G_CONST_RETURN GList* gst_element_factory_get_pad_templates
                                            (GstElementFactory *factory);
guint       gst_element_factory_get_uri_type
                                            (GstElementFactory *factory);
gchar**     gst_element_factory_get_uri_protocols
                                            (GstElementFactory *factory);
GstElement* gst_element_factory_create      (GstElementFactory *factory,
                                             const gchar *name);
GstElement* gst_element_factory_make        (const gchar *factoryname,
                                             const gchar *name);
gboolean    gst_element_factory_can_src_caps
                                            (GstElementFactory *factory,
                                             const GstCaps *caps);
gboolean    gst_element_factory_can_sink_caps
                                            (GstElementFactory *factory,
                                             const GstCaps *caps);

Object Hierarchy


  GObject
   +----GstPluginFeature
         +----GstElementFactory

Description

GstElementFactory is used to create instances of elements. A GstElementfactory can be added to a GstPlugin as it is also a GstPluginFeature.

Use gst_element_factory_new() to create a new factory which can be added to a plugin with gst_plugin_add_feature().

gst_element_factory_add_pad_template() is used to add a padtemplate to the factory. This function will enable the application to query for elementfactories that handle a specific media type.

Use the gst_element_factory_find() and gst_element_factory_create() functions to create element instances or use gst_element_factory_make() as a convenient shortcut.

The following code example shows you how to create a GstFileSrc element.

  include <gst/gst.h>

  GstElement *src;
  GstElementFactory *srcfactory;

  gst_init(&argc,&argv);

  srcfactory = gst_element_factory_find("filesrc");
  g_return_if_fail(srcfactory != NULL);

  src = gst_element_factory_create(srcfactory,"src");
  g_return_if_fail(src != NULL);
  ...

An elementfactory can be assigned a rank with gst_element_factory_set_rank() so that the autopluggers can select a plugin more appropriatly

Details

struct GstElementFactory

struct GstElementFactory;

gst_element_register ()

gboolean    gst_element_register            (GstPlugin *plugin,
                                             const gchar *name,
                                             guint rank,
                                             GType type);

Create a new elementfactory capable of instantiating objects of the given type.

`plugin` :	GstPlugin to register the element with
`name` :	name of elements of this type
`rank` :	rank of element (higher rank means more importance when autoplugging)
`type` :	GType of element to register
Returns :	TRUE, if the registering succeeded, FALSE on error

gst_element_factory_find ()

GstElementFactory* gst_element_factory_find (const gchar *name);

Search for an element factory of the given name.

`name` :	name of factory to find
Returns :	GstElementFactory if found, NULL otherwise

gst_element_factory_get_element_type ()

GType       gst_element_factory_get_element_type
                                            (GstElementFactory *factory);

Get the GType for elements managed by this factory

`factory` :	factory to get managed GType from
Returns :	the GType for elements managed by this factory

gst_element_factory_get_longname ()

G_CONST_RETURN gchar* gst_element_factory_get_longname
                                            (GstElementFactory *factory);

Gets the longname for this factory

`factory` :	a GstElementFactory
Returns :	the longname

gst_element_factory_get_klass ()

G_CONST_RETURN gchar* gst_element_factory_get_klass
                                            (GstElementFactory *factory);

`factory` :
Returns :

gst_element_factory_get_description ()

G_CONST_RETURN gchar* gst_element_factory_get_description
                                            (GstElementFactory *factory);

Gets the description for this factory.

`factory` :	a GstElementFactory
Returns :	the description

gst_element_factory_get_author ()

G_CONST_RETURN gchar* gst_element_factory_get_author
                                            (GstElementFactory *factory);

Gets the author for this factory.

`factory` :	a GstElementFactory
Returns :	the author

gst_element_factory_get_num_pad_templates ()

guint       gst_element_factory_get_num_pad_templates
                                            (GstElementFactory *factory);

Gets the number of pad_templates in this factory.

`factory` :	a GstElementFactory
Returns :	the number of pad_templates

gst_element_factory_get_pad_templates ()

G_CONST_RETURN GList* gst_element_factory_get_pad_templates
                                            (GstElementFactory *factory);

Gets the GList of padtemplates for this factory.

`factory` :	a GstElementFactory
Returns :	the padtemplates

gst_element_factory_get_uri_type ()

guint       gst_element_factory_get_uri_type
                                            (GstElementFactory *factory);

Gets the type of URIs the element supports or GST_URI_UNKNOWN if none.

`factory` :	a GstElementFactory
Returns :	type of URIs this element supports

gst_element_factory_get_uri_protocols ()

gchar**     gst_element_factory_get_uri_protocols
                                            (GstElementFactory *factory);

Gets a NULL-terminated array of protocols this element supports or NULL, if no protocols are supported. You may not change the contents of the returned array as it is still ownt by the element factory. Use g_strdupv() if you want to.

`factory` :	a GstElementFactory
Returns :	the supported protocols or NULL

gst_element_factory_create ()

GstElement* gst_element_factory_create      (GstElementFactory *factory,
                                             const gchar *name);

Create a new element of the type defined by the given elementfactory. It will be given the name supplied, since all elements require a name as their first argument.

`factory` :	factory to instantiate
`name` :	name of new element
Returns :	new GstElement or NULL if the element couldn't be created

gst_element_factory_make ()

GstElement* gst_element_factory_make        (const gchar *factoryname,
                                             const gchar *name);

Create a new element of the type defined by the given element factory. If name is NULL, then the element will receive a guaranteed unique name, consisting of the element factory name and a number. If name is given, it will be given the name supplied.

`factoryname` :	a named factory to instantiate
`name` :	name of new element
Returns :	new GstElement or NULL if unable to create element

gst_element_factory_can_src_caps ()

gboolean    gst_element_factory_can_src_caps
                                            (GstElementFactory *factory,
                                             const GstCaps *caps);

Checks if the factory can source the given capability.

`factory` :	factory to query
`caps` :	the caps to check
Returns :	true if it can src the capabilities

gst_element_factory_can_sink_caps ()

gboolean    gst_element_factory_can_sink_caps
                                            (GstElementFactory *factory,
                                             const GstCaps *caps);

Checks if the factory can sink the given capability.

`factory` :	factory to query
`caps` :	the caps to check
Returns :	true if it can sink the capabilities