1/* GStreamer
2 * Copyright (C) 2003 Benjamin Otte <in7y118@public.uni-hamburg.de>
3 *
4 * gsttypefind.h: typefinding subsystem
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
15 *
16 * You should have received a copy of the GNU Library General Public
17 * License along with this library; if not, write to the
18 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
19 * Boston, MA 02110-1301, USA.
20 */
21
22
23#ifndef __GST_TYPE_FIND_H__
24#define __GST_TYPE_FIND_H__
25
26#include <gst/gstcaps.h>
27#include <gst/gstplugin.h>
28#include <gst/gstpluginfeature.h>
29
30G_BEGIN_DECLS
31
32#define GST_TYPE_TYPE_FIND (gst_type_find_get_type())
33
34typedef struct _GstTypeFind GstTypeFind;
35
36/**
37 * GstTypeFindFunction:
38 * @find: A #GstTypeFind structure
39 * @user_data: optional data to pass to the function
40 *
41 * A function that will be called by typefinding.
42 */
43typedef void (* GstTypeFindFunction) (GstTypeFind *find, gpointer user_data);
44
45/**
46 * GstTypeFindProbability:
47 * @GST_TYPE_FIND_NONE: type undetected.
48 * @GST_TYPE_FIND_MINIMUM: unlikely typefind.
49 * @GST_TYPE_FIND_POSSIBLE: possible type detected.
50 * @GST_TYPE_FIND_LIKELY: likely a type was detected.
51 * @GST_TYPE_FIND_NEARLY_CERTAIN: nearly certain that a type was detected.
52 * @GST_TYPE_FIND_MAXIMUM: very certain a type was detected.
53 *
54 * The probability of the typefind function. Higher values have more certainty
55 * in doing a reliable typefind.
56 */
57typedef enum {
58 GST_TYPE_FIND_NONE = 0,
59 GST_TYPE_FIND_MINIMUM = 1,
60 GST_TYPE_FIND_POSSIBLE = 50,
61 GST_TYPE_FIND_LIKELY = 80,
62 GST_TYPE_FIND_NEARLY_CERTAIN = 99,
63 GST_TYPE_FIND_MAXIMUM = 100
64} GstTypeFindProbability;
65
66/**
67 * GstTypeFind:
68 * @peek: Method to peek data.
69 * @suggest: Method to suggest #GstCaps with a given probability.
70 * @data: The data used by the caller of the typefinding function.
71 * @get_length: Returns the length of current data.
72 *
73 * Object that stores typefind callbacks. To use with #GstTypeFindFactory.
74 */
75struct _GstTypeFind {
76 /* private to the caller of the typefind function */
77 const guint8 * (* peek) (gpointer data,
78 gint64 offset,
79 guint size);
80
81 void (* suggest) (gpointer data,
82 guint probability,
83 GstCaps *caps);
84
85 gpointer data;
86
87 /* optional */
88 guint64 (* get_length) (gpointer data);
89
90 /* <private> */
91 gpointer _gst_reserved[GST_PADDING];
92};
93
94GST_API
95GType gst_type_find_get_type (void);
96
97/* typefind function interface */
98
99GST_API
100const guint8 * gst_type_find_peek (GstTypeFind * find,
101 gint64 offset,
102 guint size);
103GST_API
104void gst_type_find_suggest (GstTypeFind * find,
105 guint probability,
106 GstCaps * caps);
107GST_API
108void gst_type_find_suggest_simple (GstTypeFind * find,
109 guint probability,
110 const char * media_type,
111 const char * fieldname, ...);
112GST_API
113guint64 gst_type_find_get_length (GstTypeFind * find);
114
115/* registration interface */
116
117GST_API
118gboolean gst_type_find_register (GstPlugin * plugin,
119 const gchar * name,
120 guint rank,
121 GstTypeFindFunction func,
122 const gchar * extensions,
123 GstCaps * possible_caps,
124 gpointer data,
125 GDestroyNotify data_notify);
126
127G_END_DECLS
128
129#endif /* __GST_TYPE_FIND_H__ */
130