2 * Copyright (C) 2003 David A. Schleef <ds@schleef.org>
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
14 * You should have received a copy of the GNU Library General Public
15 * License along with this library; if not, write to the
16 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 * Boston, MA 02111-1307, USA.
20 #ifndef __GST_CAPS_H__
21 #define __GST_CAPS_H__
23 #include <gst/gstconfig.h>
24 #include <gst/gstminiobject.h>
25 #include <gst/gststructure.h>
26 #include <gst/glib-compat.h>
30 extern GType _gst_caps_type;
32 #define GST_TYPE_CAPS (_gst_caps_type)
33 #define GST_IS_CAPS(obj) (GST_IS_MINI_OBJECT_TYPE((obj), GST_TYPE_CAPS))
34 #define GST_CAPS_CAST(obj) ((GstCaps*)(obj))
35 #define GST_CAPS(obj) (GST_CAPS_CAST(obj))
37 #define GST_TYPE_STATIC_CAPS (gst_static_caps_get_type())
41 * @GST_CAPS_FLAGS_ANY: Caps has no specific content, but can contain
44 * Extra flags for a caps.
47 GST_CAPS_FLAGS_ANY = (GST_MINI_OBJECT_FLAG_LAST << 0)
51 * GstCapsIntersectMode:
52 * @GST_CAPS_INTERSECT_ZIG_ZAG : Zig-zags over both caps.
53 * @GST_CAPS_INTERSECT_FIRST : Keeps the first caps order.
55 * Modes of caps intersection
57 * @GST_CAPS_INTERSECT_ZIG_ZAG tries to preserve overall order of both caps
58 * by iterating on the caps' structures as the following matrix shows:
66 * Used when there is no explicit precedence of one caps over the other. e.g.
67 * tee's sink pad getcaps function, it will probe its src pad peers' for their
68 * caps and intersect them with this mode.
70 * @GST_CAPS_INTERSECT_FIRST is useful when an element wants to preserve
71 * another element's caps priority order when intersecting with its own caps.
72 * Example: If caps1 is [A, B, C] and caps2 is [E, B, D, A], the result
73 * would be [A, B], maintaining the first caps priority on the intersection.
78 GST_CAPS_INTERSECT_ZIG_ZAG = 0,
79 GST_CAPS_INTERSECT_FIRST = 1
80 } GstCapsIntersectMode;
85 * Means that the element/pad can output 'anything'. Useful for elements
86 * that output unknown media, such as filesrc.
88 #define GST_CAPS_ANY gst_caps_new_any()
92 * The opposite of %GST_CAPS_ANY: it means that the pad/element outputs an
93 * undefined media type that can not be detected.
95 #define GST_CAPS_NONE gst_caps_new_empty()
98 * GST_STATIC_CAPS_ANY:
100 * Creates a new #GstCaps static caps that matches anything.
101 * This can be used in pad templates.
103 #define GST_STATIC_CAPS_ANY GST_STATIC_CAPS("ANY")
105 * GST_STATIC_CAPS_NONE:
107 * Creates a new #GstCaps static caps that matches nothing.
108 * This can be used in pad templates.
110 #define GST_STATIC_CAPS_NONE GST_STATIC_CAPS("NONE")
113 * GST_CAPS_IS_SIMPLE:
114 * @caps: the #GstCaps instance to check
116 * Convenience macro that checks if the number of structures in the given caps
119 #define GST_CAPS_IS_SIMPLE(caps) (gst_caps_get_size(caps) == 1)
123 * @string: the string describing the caps
125 * Creates a new #GstCaps static caps from an input string.
126 * This can be used in pad templates.
128 #define GST_STATIC_CAPS(string) \
130 /* miniobject */ { { 0, 0, 0, 0, NULL, NULL, NULL }, \
132 /* string */ string, \
136 typedef struct _GstCaps GstCaps;
137 typedef struct _GstStaticCaps GstStaticCaps;
143 * A flags word containing #GstCapsFlags flags set on this caps.
145 #define GST_CAPS_FLAGS(caps) GST_MINI_OBJECT_FLAGS(caps)
152 * Get access to the reference count field of the caps
154 #define GST_CAPS_REFCOUNT(caps) GST_MINI_OBJECT_REFCOUNT(caps)
156 * GST_CAPS_REFCOUNT_VALUE:
159 * Get the reference count value of the caps.
161 #define GST_CAPS_REFCOUNT_VALUE(caps) GST_MINI_OBJECT_REFCOUNT_VALUE(caps)
164 * GST_CAPS_FLAG_IS_SET:
166 * @flag: the #GstCapsFlags to check.
168 * Gives the status of a specific flag on a caps.
170 #define GST_CAPS_FLAG_IS_SET(caps,flag) GST_MINI_OBJECT_FLAG_IS_SET (caps, flag)
174 * @flag: the #GstCapsFlags to set.
176 * Sets a caps flag on a caps.
178 #define GST_CAPS_FLAG_SET(caps,flag) GST_MINI_OBJECT_FLAG_SET (caps, flag)
180 * GST_CAPS_FLAG_UNSET:
182 * @flag: the #GstCapsFlags to clear.
184 * Clears a caps flag.
186 #define GST_CAPS_FLAG_UNSET(caps,flag) GST_MINI_OBJECT_FLAG_UNSET (caps, flag)
191 * @caps: the #GstCaps to reference
193 * Add a reference to a #GstCaps object.
195 * From this point on, until the caller calls gst_caps_unref() or
196 * gst_caps_make_writable(), it is guaranteed that the caps object will not
197 * change. This means its structures won't change, etc. To use a #GstCaps
198 * object, you must always have a refcount on it -- either the one made
199 * implicitly by e.g. gst_caps_new_simple(), or via taking one explicitly with
202 * Returns: the same #GstCaps object.
204 #ifdef _FOOL_GTK_DOC_
205 G_INLINE_FUNC GstCaps * gst_caps_ref (GstCaps * caps);
208 static inline GstCaps *
209 gst_caps_ref (GstCaps * caps)
211 return (GstCaps *) gst_mini_object_ref (GST_MINI_OBJECT_CAST (caps));
218 * Unref a #GstCaps and and free all its structures and the
219 * structures' values when the refcount reaches 0.
221 #ifdef _FOOL_GTK_DOC_
222 G_INLINE_FUNC void gst_caps_unref (GstCaps * caps);
226 gst_caps_unref (GstCaps * caps)
228 gst_mini_object_unref (GST_MINI_OBJECT_CAST (caps));
236 * Creates a new #GstCaps as a copy of the old @caps. The new caps will have a
237 * refcount of 1, owned by the caller. The structures are copied as well.
239 * Note that this function is the semantic equivalent of a gst_caps_ref()
240 * followed by a gst_caps_make_writable(). If you only want to hold on to a
241 * reference to the data, you should use gst_caps_ref().
243 * When you are finished with the caps, call gst_caps_unref() on it.
245 * Returns: the new #GstCaps
247 #ifdef _FOOL_GTK_DOC_
248 G_INLINE_FUNC GstCaps * gst_caps_copy (const GstCaps * caps);
251 static inline GstCaps *
252 gst_caps_copy (const GstCaps * caps)
254 return GST_CAPS (gst_mini_object_copy (GST_MINI_OBJECT_CAST (caps)));
258 * gst_caps_is_writable:
261 * Tests if you can safely modify @caps. It is only safe to modify caps when
262 * there is only one owner of the caps - ie, the refcount is 1.
264 #define gst_caps_is_writable(caps) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (caps))
267 * gst_caps_make_writable:
268 * @caps: (transfer full): a #GstCaps
270 * Returns a writable copy of @caps.
272 * If there is only one reference count on @caps, the caller must be the owner,
273 * and so this function will return the caps object unchanged. If on the other
274 * hand there is more than one reference on the object, a new caps object will
275 * be returned. The caller's reference on @caps will be removed, and instead the
276 * caller will own a reference to the returned object.
278 * In short, this function unrefs the caps in the argument and refs the caps
279 * that it returns. Don't access the argument after calling this function. See
280 * also: gst_caps_ref().
282 * Returns: (transfer full): a writable caps which may or may not be the
285 #define gst_caps_make_writable(caps) GST_CAPS_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (caps)))
289 * @ocaps: (inout) (transfer full): pointer to a pointer to a #GstCaps to be
291 * @ncaps: (transfer none) (allow-none): pointer to a #GstCaps that will
292 * replace the caps pointed to by @ocaps.
294 * Modifies a pointer to a #GstCaps to point to a different #GstCaps. The
295 * modification is done atomically (so this is useful for ensuring thread safety
296 * in some cases), and the reference counts are updated appropriately (the old
297 * caps is unreffed, the new is reffed).
299 * Either @ncaps or the #GstCaps pointed to by @ocaps may be NULL.
301 #define gst_caps_replace(ocaps,ncaps) \
303 GstCaps **___ocapsaddr = (GstCaps **)(ocaps); \
304 gst_mini_object_replace ((GstMiniObject **)___ocapsaddr, \
305 GST_MINI_OBJECT_CAST (ncaps)); \
310 * @mini_object: the parent type
312 * Object describing media types.
315 GstMiniObject mini_object;
323 * @caps: the cached #GstCaps
324 * @string: a string describing a caps
326 * Datastructure to initialize #GstCaps from a string description usually
327 * used in conjunction with GST_STATIC_CAPS() and gst_static_caps_get() to
328 * instantiate a #GstCaps.
330 struct _GstStaticCaps {
336 gpointer _gst_reserved[GST_PADDING];
339 GType gst_caps_get_type (void);
341 GstCaps * gst_caps_new_empty (void);
342 GstCaps * gst_caps_new_any (void);
343 GstCaps * gst_caps_new_simple (const char *media_type,
344 const char *fieldname,
346 GstCaps * gst_caps_new_full (GstStructure *struct1, ...);
347 GstCaps * gst_caps_new_full_valist (GstStructure *structure,
350 GType gst_static_caps_get_type (void);
351 GstCaps * gst_static_caps_get (GstStaticCaps *static_caps);
352 void gst_static_caps_cleanup (GstStaticCaps *static_caps);
355 void gst_caps_append (GstCaps *caps1,
357 void gst_caps_merge (GstCaps *caps1,
359 void gst_caps_append_structure (GstCaps *caps,
360 GstStructure *structure);
361 void gst_caps_remove_structure (GstCaps *caps, guint idx);
362 void gst_caps_merge_structure (GstCaps *caps,
363 GstStructure *structure);
364 guint gst_caps_get_size (const GstCaps *caps);
365 GstStructure * gst_caps_get_structure (const GstCaps *caps,
367 GstStructure * gst_caps_steal_structure (GstCaps *caps,
369 GstCaps * gst_caps_copy_nth (const GstCaps *caps, guint nth);
370 void gst_caps_truncate (GstCaps *caps);
371 void gst_caps_set_value (GstCaps *caps,
373 const GValue *value);
374 void gst_caps_set_simple (GstCaps *caps,
375 const char *field, ...) G_GNUC_NULL_TERMINATED;
376 void gst_caps_set_simple_valist (GstCaps *caps,
381 gboolean gst_caps_is_any (const GstCaps *caps);
382 gboolean gst_caps_is_empty (const GstCaps *caps);
383 gboolean gst_caps_is_fixed (const GstCaps *caps);
384 gboolean gst_caps_is_always_compatible (const GstCaps *caps1,
385 const GstCaps *caps2);
386 gboolean gst_caps_is_subset (const GstCaps *subset,
387 const GstCaps *superset);
388 gboolean gst_caps_is_subset_structure (const GstCaps *caps,
389 const GstStructure *structure);
390 gboolean gst_caps_is_equal (const GstCaps *caps1,
391 const GstCaps *caps2);
392 gboolean gst_caps_is_equal_fixed (const GstCaps *caps1,
393 const GstCaps *caps2);
394 gboolean gst_caps_can_intersect (const GstCaps * caps1,
395 const GstCaps * caps2);
399 GstCaps * gst_caps_intersect (const GstCaps *caps1,
400 const GstCaps *caps2);
401 GstCaps * gst_caps_intersect_full (const GstCaps *caps1,
402 const GstCaps *caps2,
403 GstCapsIntersectMode mode);
404 GstCaps * gst_caps_subtract (const GstCaps *minuend,
405 const GstCaps *subtrahend);
406 GstCaps * gst_caps_union (const GstCaps *caps1,
407 const GstCaps *caps2);
408 GstCaps * gst_caps_normalize (const GstCaps *caps);
409 gboolean gst_caps_do_simplify (GstCaps *caps);
411 void gst_caps_fixate (GstCaps *caps);
414 gchar * gst_caps_to_string (const GstCaps *caps);
415 GstCaps * gst_caps_from_string (const gchar *string);
419 #endif /* __GST_CAPS_H__ */