ges: Implement the GESExtractable interface

+ Generate the documentation

Note: Do not compile (add to Makefile.am) for now as we are missing pieces at that point

Co-Authored-By: Volodymyr Rudyi <vladimir.rudoy@gmail.com>

docs/libs/ges-docs.sgml

@@ -94,6 +94,7 @@ platform as well as Windows. It is released under the GNU Library General Public
   <chapter>
     <title>Interfaces</title>
     <xi:include href="xml/ges-meta-container.xml"/>
+    <xi:include href="xml/ges-extractable.xml"/>
   </chapter>
 
   <chapter id="ges-hierarchy">

docs/libs/ges-sections.txt

@@ -297,7 +297,7 @@ GES_TYPE_TIMELINE
 GESTimelineLayer
 GESTimelineLayerClass
 ges_timeline_layer_add_object
-ges_timeline_layer_add_asset
+ges_timeline_layer_add_material
 ges_timeline_layer_new
 ges_timeline_layer_remove_object
 ges_timeline_layer_set_priority
@@ -928,6 +928,23 @@ GES_TYPE_META_CONTAINER
 ges_meta_container_get_ype
 </SECTION>
 
+<SECTION>
+<FILE>ges-extractable</FILE>
+<TITLE>GESExtractableInterface</TITLE>
+GESExtractable
+GESExtractableInterface
+GESExtractableCheckId
+ges_extractable_get_asset
+ges_extractable_set_asset
+ges_extractable_get_id
+<SUBSECTION Standard>
+GES_IS_EXTRACTABLE
+GES_EXTRACTABLE
+GES_EXTRACTABLE_GET_INTERFACE
+GES_TYPE_EXTRACTABLE
+ges_extractable_get_type
+</SECTION>
+
 <SECTION>
 <FILE>ges-asset</FILE>
 <TITLE>GESAsset</TITLE>

ges/ges-extractable.c

@@ -0,0 +1,289 @@
+/* GStreamer Editing Services
+ *
+ * Copyright (C) 2012 Thibault Saunier <thibault.saunier@collabora.com>
+ * Copyright (C) 2012 Volodymyr Rudyi <vladimir.rudoy@gmail.com>
+ *
+ * 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.
+ */
+/**
+ * SECTION: ges-extractable
+ * @short_description: An interface letting an object be extracted from a #GESAsset
+ *
+ * FIXME: Long description needed
+ */
+#include "ges-asset.h"
+#include "ges-internal.h"
+#include "ges-extractable.h"
+#include "ges-timeline-file-source.h"
+
+static GQuark ges_asset_key;
+
+G_DEFINE_INTERFACE_WITH_CODE (GESExtractable, ges_extractable,
+    G_TYPE_INITIALLY_UNOWNED,
+    ges_asset_key = g_quark_from_static_string ("ges-extractable-data"));
+
+static gchar *
+ges_extractable_check_id_default (GType type, const gchar * id, GError ** error)
+{
+  return g_strdup (g_type_name (type));
+}
+
+static GType
+ges_extractable_get_real_extractable_type_default (GType type, const gchar * id)
+{
+  return type;
+}
+
+static GParameter *
+extractable_get_parameters_from_id (const gchar * id, guint * n_params)
+{
+  *n_params = 0;
+
+  return NULL;
+}
+
+static gchar *
+extractable_get_id (GESExtractable * self)
+{
+  return g_strdup (g_type_name (G_OBJECT_TYPE (self)));
+
+}
+
+static void
+ges_extractable_default_init (GESExtractableInterface * iface)
+{
+  iface->asset_type = GES_TYPE_ASSET;
+  iface->check_id = ges_extractable_check_id_default;
+  iface->get_real_extractable_type =
+      ges_extractable_get_real_extractable_type_default;
+  iface->get_parameters_from_id = extractable_get_parameters_from_id;
+  iface->set_asset = NULL;
+  iface->get_id = extractable_get_id;
+  iface->register_metas = NULL;
+  iface->can_update_asset = FALSE;
+}
+
+/**
+ * ges_extractable_get_asset:
+ * @self: The #GESExtractable from which to retrieve a #GESAsset from
+ *
+ * Method to get a asset from a #GESExtractable
+ *
+ * Returns: (transfer none): the #GESAsset or %NULL if none have been set
+ */
+GESAsset *
+ges_extractable_get_asset (GESExtractable * self)
+{
+  g_return_val_if_fail (GES_IS_EXTRACTABLE (self), NULL);
+
+  return g_object_get_qdata (G_OBJECT (self), ges_asset_key);;
+}
+
+/**
+ * ges_extractable_set_asset:
+ * @self: Target object
+ * @asset: (transfer none): The #GESAsset to set
+ *
+ * Method to set asset which was used to instaniate specified object
+ */
+void
+ges_extractable_set_asset (GESExtractable * self, GESAsset * asset)
+{
+  GESExtractableInterface *iface;
+
+  g_return_if_fail (GES_IS_EXTRACTABLE (self));
+
+  iface = GES_EXTRACTABLE_GET_INTERFACE (self);
+  GST_DEBUG_OBJECT (self, "Setting asset to %" GST_PTR_FORMAT, asset);
+
+  if (iface->can_update_asset == FALSE &&
+      g_object_get_qdata (G_OBJECT (self), ges_asset_key)) {
+    GST_WARNING_OBJECT (self, "Can not reset asset on object");
+
+    return;
+  }
+
+  g_object_set_qdata_full (G_OBJECT (self), ges_asset_key,
+      gst_object_ref (asset), gst_object_unref);
+
+  /* Let classes that implement the interface know that a asset has been set */
+  if (iface->set_asset)
+    iface->set_asset (self, asset);
+}
+
+/**
+ * ges_extractable_get_id:
+ * @self: The #GESExtractable
+ *
+ * Returns: The #id of the associated #GESAsset, free with #g_free
+ */
+gchar *
+ges_extractable_get_id (GESExtractable * self)
+{
+  g_return_val_if_fail (GES_IS_EXTRACTABLE (self), NULL);
+
+  return GES_EXTRACTABLE_GET_INTERFACE (self)->get_id (self);
+}
+
+/**
+ * ges_extractable_type_get_parameters_for_id:
+ * @type: The #GType implementing #GESExtractable
+ * @id: The ID of the Extractable
+ * @n_params: (out): Return location for the returned array
+ *
+ * Returns: (transfer full) (array length=n_params): an array of #GParameter
+ * needed to extract the #GESExtractable from a #GESAsset of @id
+ */
+GParameter *
+ges_extractable_type_get_parameters_from_id (GType type, const gchar * id,
+    guint * n_params)
+{
+  GObjectClass *klass;
+  GESExtractableInterface *iface;
+
+  GParameter *ret = NULL;
+
+  g_return_val_if_fail (g_type_is_a (type, G_TYPE_OBJECT), NULL);
+  g_return_val_if_fail (g_type_is_a (type, GES_TYPE_EXTRACTABLE), NULL);
+
+  klass = g_type_class_ref (type);
+  iface = g_type_interface_peek (klass, GES_TYPE_EXTRACTABLE);
+
+  ret = iface->get_parameters_from_id (id, n_params);
+
+  g_type_class_unref (klass);
+
+  return ret;
+}
+
+/**
+ * ges_extractable_type_get_asset_type:
+ * @type: The #GType implementing #GESExtractable
+ *
+ * Get the #GType, subclass of #GES_TYPE_ASSET to instanciate
+ * to be able to extract a @type
+ *
+ * Returns: the #GType to use to create a asset to extract @type
+ */
+GType
+ges_extractable_type_get_asset_type (GType type)
+{
+  GObjectClass *klass;
+  GESExtractableInterface *iface;
+
+  g_return_val_if_fail (g_type_is_a (type, G_TYPE_OBJECT), G_TYPE_INVALID);
+  g_return_val_if_fail (g_type_is_a (type, GES_TYPE_EXTRACTABLE),
+      G_TYPE_INVALID);
+
+  klass = g_type_class_ref (type);
+
+  iface = g_type_interface_peek (klass, GES_TYPE_EXTRACTABLE);
+
+  g_type_class_unref (klass);
+
+  return iface->asset_type;
+}
+
+/**
+ * ges_extractable_type_check_id:
+ * @type: The #GType implementing #GESExtractable
+ * @id: The ID to check
+ *
+ * Check if @id is valid for @type
+ *
+ * Returns: (transfer full): A newly allocated string containing the actuall
+ * ID (after some processing) or %NULL if the ID is wrong.
+ */
+gchar *
+ges_extractable_type_check_id (GType type, const gchar * id, GError ** error)
+{
+  GObjectClass *klass;
+  GESExtractableInterface *iface;
+
+  g_return_val_if_fail (error == NULL || *error == NULL, G_TYPE_INVALID);
+  g_return_val_if_fail (g_type_is_a (type, G_TYPE_OBJECT), G_TYPE_INVALID);
+  g_return_val_if_fail (g_type_is_a (type, GES_TYPE_EXTRACTABLE),
+      G_TYPE_INVALID);
+
+  klass = g_type_class_ref (type);
+
+  iface = g_type_interface_peek (klass, GES_TYPE_EXTRACTABLE);
+
+  g_type_class_unref (klass);
+
+  return iface->check_id (type, id, error);
+}
+
+/**
+ * ges_extractable_get_real_extractable_type:
+ * @type: The #GType implementing #GESExtractable
+ * @id: The ID to check
+ *
+ * Get the #GType that should be used as extractable_type for @type and
+ * @id. Usually this will be the same as @type but in some cases they can
+ * be some subclasses of @type. For example, in the case of #GESFormatter,
+ * the returned #GType will be a subclass of #GESFormatter that can be used
+ * to load the file pointed by @id.
+ *
+ * Returns: Return the #GESExtractable type that should be used for @id
+ */
+GType
+ges_extractable_get_real_extractable_type_for_id (GType type, const gchar * id)
+{
+  GType ret;
+  GObjectClass *klass;
+  GESExtractableInterface *iface;
+
+  klass = g_type_class_ref (type);
+  iface = g_type_interface_peek (klass, GES_TYPE_EXTRACTABLE);
+  g_type_class_unref (klass);
+
+  ret = iface->get_real_extractable_type (type, id);
+
+  GST_DEBUG ("Extractable type for id %s and wanted type %s is: %s",
+      id, g_type_name (type), g_type_name (ret));
+
+  return ret;
+}
+
+/**
+ * ges_extractable_register_metas:
+ * @self: A #GESExtractable
+ * @asset: The #GESAsset on which metadatas should be registered
+ *
+ * Lets you register standard method for @extractable_type on @asset
+ *
+ * Returns: %TRUE if metas could be register %FALSE otherwize
+ */
+gboolean
+ges_extractable_register_metas (GType extractable_type, GESAsset * asset)
+{
+  GObjectClass *klass;
+  gboolean ret = FALSE;
+  GESExtractableInterface *iface;
+
+  g_return_val_if_fail (g_type_is_a (extractable_type, GES_TYPE_EXTRACTABLE),
+      FALSE);
+
+  klass = g_type_class_ref (extractable_type);
+  iface = g_type_interface_peek (klass, GES_TYPE_EXTRACTABLE);
+
+  if (iface->register_metas)
+    ret = iface->register_metas (iface, klass, asset);
+
+  g_type_class_unref (klass);
+  return ret;
+}

ges/ges-extractable.h

@@ -0,0 +1,89 @@
+/* GStreamer Editing Services
+ *
+ * Copyright (C) 2012 Thibault Saunier <thibault.saunier@collabora.com>
+ * Copyright (C) 2012 Volodymyr Rudyi <vladimir.rudoy@gmail.com>
+ *
+ * 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_
+
+#include <glib-object.h>
+#include <gio/gio.h>
+#include <ges/ges-types.h>
+#include <ges/ges-asset.h>
+
+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))
+
+GType ges_extractable_get_type (void);
+
+/**
+ * GESExtractableCheckId:
+ * @type: The #GType to check @id for:
+ * @id: The id to check
+ * @error: An error that can be set if needed
+ *
+ * Returns: The ID to use for the asset or %NULL if @id is not valid
+ */
+
+typedef gchar* (*GESExtractableCheckId) (GType type, const gchar *id,
+    GError **error);
+
+/**
+ * GESExtractable:
+ * @get_asset: A #GESExtractableGetAsset function
+ */
+struct _GESExtractableInterface
+{
+  GTypeInterface parent;
+
+  GType asset_type;
+
+  GESExtractableCheckId check_id;
+  gboolean can_update_asset;
+
+  void (*set_asset)                  (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 *class,
+                                         GESAsset *asset);
+
+  gpointer _ges_reserved[GES_PADDING];
+};
+
+GESAsset* ges_extractable_get_asset      (GESExtractable *self);
+void ges_extractable_set_asset              (GESExtractable *self,
+                                                GESAsset *asset);
+
+gchar * ges_extractable_get_id                 (GESExtractable *self);
+
+G_END_DECLS
+#endif /* _GES_EXTRACTABLE_ */

ges/ges-internal.h

@@ -87,5 +87,23 @@ ges_asset_set_proxy (GESAsset *asset, const gchar *new_id);
 G_GNUC_INTERNAL gboolean
 ges_asset_request_id_update (GESAsset *asset, gchar **proposed_id,
     GError *error);
+
+/* GESExtractable internall methods
+ *
+ * FIXME Check if that should be public later
+ */
+GType
+ges_extractable_type_get_asset_type              (GType type);
+
+G_GNUC_INTERNAL gchar *
+ges_extractable_type_check_id                    (GType type, const gchar *id, GError **error);
+
+GParameter *
+ges_extractable_type_get_parameters_from_id      (GType type, const gchar *id,
+                                                  guint *n_params);
+GType
+ges_extractable_get_real_extractable_type_for_id (GType type, const gchar * id);
+
+gboolean ges_extractable_register_metas          (GType extractable_type, GESAsset *asset);
 #endif
 #endif /* __GES_INTERNAL_H__ */

ges/ges-types.h

@@ -145,4 +145,7 @@ typedef struct _GESAsset GESAsset;
 typedef struct _GESAssetClass GESAssetClass;
 #endif
 
+typedef struct _GESExtractable GESExtractable;
+typedef struct _GESExtractableInterface GESExtractableInterface;
+
 #endif /* __GES_TYPES_H__ */

ges/ges.h

@@ -47,6 +47,7 @@
 #include <ges/ges-screenshot.h>
 #if 0
 #include <ges/ges-asset.h>
+#include <ges/ges-extractable.h>
 #endif
 
 #include <ges/ges-track.h>