/* GStreamer

 * Copyright (C) 2003 Benjamin Otte <in7y118@public.uni-hamburg.de>

 *

 * gsttypefindfactory.c: typefinding subsystem

 *

 * 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:gsttypefindfactory

 * @short_description: Information about registered typefind functions

 *

 * These functions allow querying informations about registered typefind

 * functions. How to create and register these functions is described in

 * the section <link linkend="gstreamer-Writing-typefind-functions">

 * "Writing typefind functions"</link>.

 *

 * <example>

 *   <title>how to write a simple typefinder</title>

 *   <programlisting>

 *   typedef struct {

 *     guint8 *data;

 *     guint size;

 *     guint probability;

 *     GstCaps *data;

 *   } MyTypeFind;

 *   static void

 *   my_peek (gpointer data, gint64 offset, guint size)

 *   {

 *     MyTypeFind *find = (MyTypeFind *) data;

 *     if (offset >= 0 && offset + size <= find->size) {

 *       return find->data + offset;

 *     }

 *     return NULL;

 *   }

 *   static void

 *   my_suggest (gpointer data, guint probability, GstCaps *caps)

 *   {

 *     MyTypeFind *find = (MyTypeFind *) data;

 *     if (probability > find->probability) {

 *       find->probability = probability;

 *       gst_caps_replace (&find->caps, caps);

 *     }

 *   }

 *   static GstCaps *

 *   find_type (guint8 *data, guint size)

 *   {

 *     GList *walk, *type_list;

 *     MyTypeFind find = {data, size, 0, NULL};

 *     GstTypeFind gst_find = {my_peek, my_suggest, &find, };

 *     walk = type_list = gst_type_find_factory_get_list ();

 *     while (walk) {

 *       GstTypeFindFactory *factory = GST_TYPE_FIND_FACTORY (walk->data);

 *       walk = g_list_next (walk)

 *       gst_type_find_factory_call_function (factory, &gst_find);

 *     }

 *     g_list_free (type_list);

 *     return find.caps;

 *   };

 *   </programlisting>

 * </example>

 *

 * The above example shows how to write a very simple typefinder that

 * identifies the given data. You can get quite a bit more complicated than

 * that though.

 *

 * Last reviewed on 2005-11-09 (0.9.4)

 */

#include "gst_private.h"

#include "gstinfo.h"

#include "gsttypefind.h"

#include "gsttypefindfactory.h"

#include "gstregistry.h"

GST_DEBUG_CATEGORY (type_find_debug);

#define GST_CAT_DEFAULT type_find_debug

static void gst_type_find_factory_dispose (GObject * object);

static GstPluginFeatureClass *parent_class = NULL;

}

static void

{

  object_class->dispose = gst_type_find_factory_dispose;

}

static void

{

  factory->user_data = factory;

  factory->user_data_notify = NULL;

}

static void

gst_type_find_factory_dispose (GObject * object)

{

  GstTypeFindFactory *factory = GST_TYPE_FIND_FACTORY (object);

  if (factory->caps) {

    gst_caps_unref (factory->caps);

    factory->caps = NULL;

  }

  if (factory->extensions) {

    g_strfreev (factory->extensions);

    factory->extensions = NULL;

  }

  if (factory->user_data_notify && factory->user_data) {

    factory->user_data_notify (factory->user_data);

    factory->user_data = NULL;

  }

  G_OBJECT_CLASS (parent_class)->dispose (object);

}

/**

 * gst_type_find_factory_get_list:

 *

 * Gets the list of all registered typefind factories. You must free the

 * list using gst_plugin_feature_list_free.

 *

 * Returns: the list of all registered #GstTypeFindFactory.

 */

#ifdef __SYMBIAN32__

EXPORT_C

#endif

GList *

gst_type_find_factory_get_list (void)

{

  return gst_registry_get_feature_list (gst_registry_get_default (),

      GST_TYPE_TYPE_FIND_FACTORY);

}

/**

 * gst_type_find_factory_get_caps:

 * @factory: A #GstTypeFindFactory

 *

 * Gets the #GstCaps associated with a typefind factory.

 *

 * Returns: The #GstCaps associated with this factory

 */

#ifdef __SYMBIAN32__

EXPORT_C

#endif

GstCaps *

gst_type_find_factory_get_caps (GstTypeFindFactory * factory)

{

  g_return_val_if_fail (GST_IS_TYPE_FIND_FACTORY (factory), NULL);

  return factory->caps;

}

/**

 * gst_type_find_factory_get_extensions:

 * @factory: A #GstTypeFindFactory

 *

 * Gets the extensions associated with a #GstTypeFindFactory. The returned

 * array should not be changed. If you need to change stuff in it, you should

 * copy it using g_stdupv().  This function may return NULL to indicate

 * a 0-length list.

 *

 * Returns: a NULL-terminated array of extensions associated with this factory

 */

#ifdef __SYMBIAN32__

EXPORT_C

#endif

gchar **

gst_type_find_factory_get_extensions (GstTypeFindFactory * factory)

{

  g_return_val_if_fail (GST_IS_TYPE_FIND_FACTORY (factory), NULL);

  return factory->extensions;

}

/**

 * gst_type_find_factory_call_function:

 * @factory: A #GstTypeFindFactory

 * @find: A properly setup #GstTypeFind entry. The get_data and suggest_type

 *        members must be set.

 *

 * Calls the #GstTypeFindFunction associated with this factory.

 */

#ifdef __SYMBIAN32__

EXPORT_C

#endif

void

gst_type_find_factory_call_function (GstTypeFindFactory * factory,

    GstTypeFind * find)

{

  GstTypeFindFactory *new_factory;

  g_return_if_fail (GST_IS_TYPE_FIND_FACTORY (factory));

  g_return_if_fail (find != NULL);

  g_return_if_fail (find->peek != NULL);

  g_return_if_fail (find->suggest != NULL);

  new_factory =

      GST_TYPE_FIND_FACTORY (gst_plugin_feature_load (GST_PLUGIN_FEATURE

          (factory)));

  if (new_factory) {

    gst_object_unref (new_factory);

  }

}