Using an element factory

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#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);
...

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 type and add the factory to plugin .

gst_element_factory_find ()

GstElementFactory *
gst_element_factory_find (const gchar *name);

Search for an element factory of the given name. Refs the returned element factory; caller is responsible for unreffing.

gst_element_factory_get_element_type ()

GType
gst_element_factory_get_element_type (GstElementFactory *factory);

Get the GType for elements managed by this factory. The type can only be retrieved if the element factory is loaded, which can be assured with gst_plugin_feature_load().

gst_element_factory_get_metadata ()

const gchar *
gst_element_factory_get_metadata (GstElementFactory *factory,
                                  const gchar *key);

Get the metadata on factory with key .

gst_element_factory_get_metadata_keys ()

gchar **
gst_element_factory_get_metadata_keys (GstElementFactory *factory);

Get the available keys for the metadata on factory .

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.

gst_element_factory_get_uri_type ()

GstURIType
gst_element_factory_get_uri_type (GstElementFactory *factory);

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

gst_element_factory_get_uri_protocols ()

const gchar * const *
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 owned by the element factory. Use g_strdupv() to make a copy of the protocol string array if you need to.

gst_element_factory_has_interface ()

gboolean
gst_element_factory_has_interface (GstElementFactory *factory,
                                   const gchar *interfacename);

Check if factory implements the interface with name interfacename .

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.

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.

gst_element_factory_can_sink_all_caps ()

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

Checks if the factory can sink all possible capabilities.

gst_element_factory_can_src_all_caps ()

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

Checks if the factory can src all possible capabilities.

gst_element_factory_can_sink_any_caps ()

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

Checks if the factory can sink any possible capability.

gst_element_factory_can_src_any_caps ()

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

Checks if the factory can src any possible capability.

gst_element_factory_get_static_pad_templates ()

const GList *
gst_element_factory_get_static_pad_templates
                               (GstElementFactory *factory);

Gets the GList of GstStaticPadTemplate for this factory.

gst_element_factory_list_filter ()

GList *
gst_element_factory_list_filter (GList *list,
                                 const GstCaps *caps,
                                 GstPadDirection direction,
                                 gboolean subsetonly);

Filter out all the elementfactories in list that can handle caps in the given direction.

If subsetonly is TRUE, then only the elements whose pads templates are a complete superset of caps will be returned. Else any element whose pad templates caps can intersect with caps will be returned.

gst_element_factory_list_get_elements ()

GList *
gst_element_factory_list_get_elements (GstElementFactoryListType type,
                                       GstRank minrank);

Get a list of factories that match the given type . Only elements with a rank greater or equal to minrank will be returned. The list of factories is returned by decreasing rank.

gst_element_factory_list_is_type ()

gboolean
gst_element_factory_list_is_type (GstElementFactory *factory,
                                  GstElementFactoryListType type);

Check if factory is of the given types.

GstElementFactory

typedef struct _GstElementFactory GstElementFactory;

The opaque GstElementFactory data structure.

GstElementFactoryListType

typedef guint64 GstElementFactoryListType;

GST_ELEMENT_FACTORY_TYPE_ANY

#define  GST_ELEMENT_FACTORY_TYPE_ANY ((GstElementFactoryListType)((G_GUINT64_CONSTANT (1) << 49) - 1))

Elements of any of the defined GST_ELEMENT_FACTORY_LIST types

GST_ELEMENT_FACTORY_TYPE_AUDIOVIDEO_SINKS

#define GST_ELEMENT_FACTORY_TYPE_AUDIOVIDEO_SINKS ((GstElementFactoryListType)(GST_ELEMENT_FACTORY_TYPE_SINK | GST_ELEMENT_FACTORY_TYPE_MEDIA_AUDIO | GST_ELEMENT_FACTORY_TYPE_MEDIA_VIDEO | GST_ELEMENT_FACTORY_TYPE_MEDIA_IMAGE))

All sinks handling audio, video or image media types

GST_ELEMENT_FACTORY_TYPE_AUDIO_ENCODER

#define GST_ELEMENT_FACTORY_TYPE_AUDIO_ENCODER ((GstElementFactoryListType)(GST_ELEMENT_FACTORY_TYPE_ENCODER | GST_ELEMENT_FACTORY_TYPE_MEDIA_AUDIO))

All encoders handling audio media types

GST_ELEMENT_FACTORY_TYPE_DECODABLE

#define             GST_ELEMENT_FACTORY_TYPE_DECODABLE

All elements used to 'decode' streams (decoders, demuxers, parsers, depayloaders)

GST_ELEMENT_FACTORY_TYPE_DECODER

#define  GST_ELEMENT_FACTORY_TYPE_DECODER        ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 0))

GST_ELEMENT_FACTORY_TYPE_DECRYPTOR

#define  GST_ELEMENT_FACTORY_TYPE_DECRYPTOR      ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 10))

GST_ELEMENT_FACTORY_TYPE_DEMUXER

#define  GST_ELEMENT_FACTORY_TYPE_DEMUXER        ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 5))

GST_ELEMENT_FACTORY_TYPE_DEPAYLOADER

#define  GST_ELEMENT_FACTORY_TYPE_DEPAYLOADER    ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 8))

GST_ELEMENT_FACTORY_TYPE_ENCODER

#define  GST_ELEMENT_FACTORY_TYPE_ENCODER        ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 1))

GST_ELEMENT_FACTORY_TYPE_ENCRYPTOR

#define  GST_ELEMENT_FACTORY_TYPE_ENCRYPTOR      ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 11))

GST_ELEMENT_FACTORY_TYPE_FORMATTER

#define  GST_ELEMENT_FACTORY_TYPE_FORMATTER      ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 9))

GST_ELEMENT_FACTORY_TYPE_MAX_ELEMENTS

#define  GST_ELEMENT_FACTORY_TYPE_MAX_ELEMENTS   ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 48))

GST_ELEMENT_FACTORY_TYPE_MEDIA_AUDIO

#define  GST_ELEMENT_FACTORY_TYPE_MEDIA_AUDIO    ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 50))

GST_ELEMENT_FACTORY_TYPE_MEDIA_IMAGE

#define  GST_ELEMENT_FACTORY_TYPE_MEDIA_IMAGE    ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 51))

GST_ELEMENT_FACTORY_TYPE_MEDIA_METADATA

#define  GST_ELEMENT_FACTORY_TYPE_MEDIA_METADATA ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 53))

GST_ELEMENT_FACTORY_TYPE_MEDIA_SUBTITLE

#define  GST_ELEMENT_FACTORY_TYPE_MEDIA_SUBTITLE ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 52))

GST_ELEMENT_FACTORY_TYPE_MEDIA_VIDEO

#define  GST_ELEMENT_FACTORY_TYPE_MEDIA_VIDEO    ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 49))

GST_ELEMENT_FACTORY_TYPE_MEDIA_ANY

#define GST_ELEMENT_FACTORY_TYPE_MEDIA_ANY ((GstElementFactoryListType)(~G_GUINT64_CONSTANT (0) << 48))

Elements matching any of the defined GST_ELEMENT_FACTORY_TYPE_MEDIA types

Note: Do not use this if you wish to not filter against any of the defined media types. If you wish to do this, simply don't specify any GST_ELEMENT_FACTORY_TYPE_MEDIA flag.

GST_ELEMENT_FACTORY_TYPE_MUXER

#define  GST_ELEMENT_FACTORY_TYPE_MUXER          ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 4))

GST_ELEMENT_FACTORY_TYPE_PARSER

#define  GST_ELEMENT_FACTORY_TYPE_PARSER         ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 6))

GST_ELEMENT_FACTORY_TYPE_PAYLOADER

#define  GST_ELEMENT_FACTORY_TYPE_PAYLOADER      ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 7))

GST_ELEMENT_FACTORY_TYPE_SINK

#define  GST_ELEMENT_FACTORY_TYPE_SINK           ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 2))

GST_ELEMENT_FACTORY_TYPE_SRC

#define  GST_ELEMENT_FACTORY_TYPE_SRC            ((GstElementFactoryListType)(G_GUINT64_CONSTANT (1) << 3))

GST_ELEMENT_FACTORY_TYPE_VIDEO_ENCODER

#define GST_ELEMENT_FACTORY_TYPE_VIDEO_ENCODER ((GstElementFactoryListType)(GST_ELEMENT_FACTORY_TYPE_ENCODER | GST_ELEMENT_FACTORY_TYPE_MEDIA_VIDEO | GST_ELEMENT_FACTORY_TYPE_MEDIA_IMAGE))

All encoders handling video or image media types