/* GStreamer * Copyright (C) 2003 Benjamin Otte <in7y118@public.uni-hamburg.de> * * gsttypefind.h: 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., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, USA. */ #ifndef __GST_TYPE_FIND_H__ #define __GST_TYPE_FIND_H__ #include <gst/gstcaps.h> #include <gst/gstplugin.h> #include <gst/gstpluginfeature.h> G_BEGIN_DECLS /** * GST_TYPE_FIND_REGISTER_DEFINE_CUSTOM: * @type_find: The type find name in lower case, with words separated by '_'. * Used to generate `gst_type_find_register_*(GstPlugin* plugin)`. * @register_func: pointer to a method with the format: `gboolean register_func (GstPlugin* plugin);` * * A convenience macro to define the entry point of a * type find `gst_type_find_register_*(GstPlugin* plugin)` which uses * register_func as the main registration method for the type find. * As an example, you may define the type find named "custom-typefind" * as following using `type_find_register_custom`: * * ``` * GST_TYPE_FIND_REGISTER_DEFINE_CUSTOM (plugin, type_find_register_custom) * ``` * * Since: 1.20 */ #define GST_TYPE_FIND_REGISTER_DEFINE_CUSTOM(type_find, register_func) \ G_BEGIN_DECLS \ gboolean G_PASTE (gst_type_find_register_, type_find) (GstPlugin * plugin) \ { \ return register_func (plugin); \ } \ G_END_DECLS /** * GST_TYPE_FIND_REGISTER_DEFINE: * @t_f: The type find name in lower case, with words separated by '_'. * Used to generate `gst_type_find_register_*(GstPlugin* plugin)`. * @t_f_n: The public name of the type find * @r: The #GstRank of the type find (higher rank means more importance when autoplugging, see #GstRank) * @func: The #GstTypeFindFunction to use * @extensions: (nullable): Optional comma-separated list of extensions * that could belong to this type * @possible_caps: (nullable): Optionally the caps that could be returned when typefinding * succeeds * @data: Optional user data. This user data must be available until the plugin * is unloaded. * @data_notify: a #GDestroyNotify that will be called on @data when the plugin * is unloaded. * * A convenience macro to define the entry point of a * type find `gst_type_find_register_*(GstPlugin* plugin)`. * * Since: 1.20 */ #define GST_TYPE_FIND_REGISTER_DEFINE(t_f, t_f_n, r, func, extensions, possible_caps, data, data_notify) \ G_BEGIN_DECLS \ gboolean G_PASTE (gst_type_find_register_, t_f) (GstPlugin * plugin) \ { \ return gst_type_find_register (plugin, t_f_n, r, func, extensions, possible_caps, data, data_notify); \ } \ G_END_DECLS /** * GST_TYPE_FIND_REGISTER_DECLARE: * @t_f: The type find name in lower case, with words separated by '_'. * * This macro can be used to declare a new type find. * It has to be used in combination with #GST_TYPE_FIND_REGISTER_DEFINE macro * and must be placed outside any block to declare the type find registration * function. * * Since: 1.20 */ #define GST_TYPE_FIND_REGISTER_DECLARE(t_f) \ G_BEGIN_DECLS \ gboolean G_PASTE(gst_type_find_register_, t_f) (GstPlugin * plugin); \ G_END_DECLS /** * GST_TYPE_FIND_REGISTER: * @t_f: The type find name in lower case, with words separated by '_'. * @plugin: The #GstPlugin where to register the type find. * * This macro can be used to register a type find into a #GstPlugin. * This method will be usually called in the plugin init function * but can also be called with a NULL plugin. * * Since: 1.20 */ #define GST_TYPE_FIND_REGISTER(t_f, plugin) G_PASTE(gst_type_find_register_, t_f) (plugin) #define GST_TYPE_TYPE_FIND (gst_type_find_get_type()) typedef struct _GstTypeFind GstTypeFind; /** * GstTypeFindFunction: * @find: A #GstTypeFind structure * @user_data: optional data to pass to the function * * A function that will be called by typefinding. */ typedef void (* GstTypeFindFunction) (GstTypeFind *find, gpointer user_data); /** * GstTypeFindProbability: * @GST_TYPE_FIND_NONE: type undetected. * @GST_TYPE_FIND_MINIMUM: unlikely typefind. * @GST_TYPE_FIND_POSSIBLE: possible type detected. * @GST_TYPE_FIND_LIKELY: likely a type was detected. * @GST_TYPE_FIND_NEARLY_CERTAIN: nearly certain that a type was detected. * @GST_TYPE_FIND_MAXIMUM: very certain a type was detected. * * The probability of the typefind function. Higher values have more certainty * in doing a reliable typefind. */ typedef enum { GST_TYPE_FIND_NONE = 0, GST_TYPE_FIND_MINIMUM = 1, GST_TYPE_FIND_POSSIBLE = 50, GST_TYPE_FIND_LIKELY = 80, GST_TYPE_FIND_NEARLY_CERTAIN = 99, GST_TYPE_FIND_MAXIMUM = 100 } GstTypeFindProbability; /** * GstTypeFind: * @peek: Method to peek data. * @suggest: Method to suggest #GstCaps with a given probability. * @data: The data used by the caller of the typefinding function. * @get_length: Returns the length of current data. * * Object that stores typefind callbacks. To use with #GstTypeFindFactory. */ struct _GstTypeFind { /* private to the caller of the typefind function */ const guint8 * (* peek) (gpointer data, gint64 offset, guint size); void (* suggest) (gpointer data, guint probability, GstCaps *caps); gpointer data; /* optional */ guint64 (* get_length) (gpointer data); /* <private> */ gpointer _gst_reserved[GST_PADDING]; }; /** * gst_type_find_get_type: (attributes doc.skip=true) */ GST_API GType gst_type_find_get_type (void); /* typefind function interface */ GST_API const guint8 * gst_type_find_peek (GstTypeFind * find, gint64 offset, guint size); GST_API void gst_type_find_suggest (GstTypeFind * find, guint probability, GstCaps * caps); GST_API void gst_type_find_suggest_simple (GstTypeFind * find, guint probability, const char * media_type, const char * fieldname, ...); GST_API guint64 gst_type_find_get_length (GstTypeFind * find); /* registration interface */ GST_API gboolean gst_type_find_register (GstPlugin * plugin, const gchar * name, guint rank, GstTypeFindFunction func, const gchar * extensions, GstCaps * possible_caps, gpointer data, GDestroyNotify data_notify); G_END_DECLS #endif /* __GST_TYPE_FIND_H__ */