/* GStreamer Editing Services * * Copyright (C) 2012 Thibault Saunier * Copyright (C) 2012 Volodymyr Rudyi * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 59 Temple Place - Suite 330, * Boston, MA 02111-1307, USA. */ #ifndef _GES_EXTRACTABLE_ #define _GES_EXTRACTABLE_ typedef struct _GESExtractable GESExtractable; #include #include #include #include #include G_BEGIN_DECLS /* GESExtractable interface declarations */ #define GES_TYPE_EXTRACTABLE (ges_extractable_get_type ()) #define GES_EXTRACTABLE(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GES_TYPE_EXTRACTABLE, GESExtractable)) #define GES_IS_EXTRACTABLE(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GES_TYPE_EXTRACTABLE)) #define GES_EXTRACTABLE_GET_INTERFACE(inst) (G_TYPE_INSTANCE_GET_INTERFACE ((inst), GES_TYPE_EXTRACTABLE, GESExtractableInterface)) GES_API GType ges_extractable_get_type (void); /** * GESExtractableCheckId: * @type: The #GESExtractable type to check @id for * @id: The ID to check * @error: An error that can be set if needed * * Method for checking that an ID is valid for the given #GESExtractable * type. If the given ID is considered valid, it can be adjusted into some * standard and returned to prevent the creation of separate #GESAsset-s, * with different #GESAsset:id, that would otherwise act the same. * * Returns (transfer full) (nullable): The actual #GESAsset:id to set on * any corresponding assets, based on @id, or %NULL if @id is not valid. */ typedef gchar* (*GESExtractableCheckId) (GType type, const gchar *id, GError **error); /** * GESExtractableInterface: * @asset_type: The subclass type of #GESAsset that should be created when * an asset with the corresponding #GESAsset:extractable-type is * requested. * @check_id: The method to call to check whether a given ID is valid as * an asset #GESAsset:id for the given #GESAsset:extractable-type. The * returned ID is the actual #GESAsset:id that is set on the asset. The * default implementation will simply always return the type name of the * #GESAsset:extractable-type, even if the received ID is %NULL. As such, * any given ID is considered valid (or is ignored), but only one is * actually ever set on an asset, which means the given * #GESAsset:extractable-type can only have one associated asset. * @can_update_asset: Whether an object of this class can have its * #GESAsset change over its lifetime. This should be set to %TRUE if one * of the object's parameters that is associated with its ID can change * after construction, which would require an asset with a new ID. Note * that the subclass is required to handle the requesting and setting of * the new asset on the object. * @set_asset: This method is called after the #GESAsset of an object is * set. If your class supports the asset of an object changing, then you * can use this method to change the parameters of the object to match the * new asset #GESAsset:id. If setting the asset should be able to fail, * you should implement @set_asset_full instead. * @set_asset_full: Like @set_asset, but also allows you to return %FALSE * to indicate a failure to change the object in response to a change in * its asset. * @get_parameters_from_id: The method to call to get the object * properties corresponding to a given asset #GESAsset:id. The default * implementation will simply return no parameters. The default #GESAsset * will call this to set the returned properties on the extracted object, * but other subclasses may ignore this method. * @get_id: The method to fetch the #GESAsset:id of some associated asset. * Note that it may be the case that the object does not have its asset * set, or even that an asset with such an #GESAsset:id does not exist in * the GES cache. Instead, this should return the #GESAsset:id that is * _compatible_ with the current state of the object. The default * implementation simply returns the type name of the object, which is * what is used as the #GESAsset:id by default. * @get_real_extractable_type: The method to call to get the actual * #GESAsset:extractable-type an asset should have set, given the * requested #GESAsset:id. The default implementation simply returns the * same type as given. You can overwrite this if it is more appropriate * to extract the object from a subclass, depending on the requested * #GESAsset:id. Note that when an asset is requested, this method will be * called before the other class methods. In particular, this means that * the @check_id and @get_parameters_from_id class methods of the returned * type will be used (instead of our own). * @register_metas: The method to set metadata on an asset. This is called * on initiation of the asset, but before it begins to load its state. */ G_GNUC_BEGIN_IGNORE_DEPRECATIONS struct _GESExtractableInterface { GTypeInterface parent; GType asset_type; GESExtractableCheckId check_id; gboolean can_update_asset; void (*set_asset) (GESExtractable *self, GESAsset *asset); gboolean (*set_asset_full) (GESExtractable *self, GESAsset *asset); GParameter *(*get_parameters_from_id) (const gchar *id, guint *n_params); gchar * (*get_id) (GESExtractable *self); GType (*get_real_extractable_type) (GType wanted_type, const gchar *id); gboolean (*register_metas) (GESExtractableInterface *self, GObjectClass *klass, GESAsset *asset); gpointer _ges_reserved[GES_PADDING]; }; G_GNUC_END_IGNORE_DEPRECATIONS GES_API GESAsset* ges_extractable_get_asset (GESExtractable *self); GES_API gboolean ges_extractable_set_asset (GESExtractable *self, GESAsset *asset); GES_API gchar * ges_extractable_get_id (GESExtractable *self); G_END_DECLS #endif /* _GES_EXTRACTABLE_ */