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., 51 Franklin St, Fifth Floor,
17 * Boston, MA 02110-1301, 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 GST_EXPORT 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_FLAG_ANY: Caps has no specific content, but can contain
44 * Extra flags for a caps.
47 GST_CAPS_FLAG_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.
76 GST_CAPS_INTERSECT_ZIG_ZAG = 0,
77 GST_CAPS_INTERSECT_FIRST = 1
78 } GstCapsIntersectMode;
83 * Means that the element/pad can output 'anything'. Useful for elements
84 * that output unknown media, such as filesrc. This macro returns a singleton and
85 * should not be unreffed.
87 #define GST_CAPS_ANY _gst_caps_any
91 * The opposite of %GST_CAPS_ANY: it means that the pad/element outputs an
92 * undefined media type that can not be detected. This macro returns a singleton
93 * and should not be unreffed.
95 #define GST_CAPS_NONE _gst_caps_none
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) \
131 /* string */ string, \
135 typedef struct _GstCaps GstCaps;
136 typedef struct _GstStaticCaps GstStaticCaps;
138 GST_EXPORT GstCaps * _gst_caps_any;
139 GST_EXPORT GstCaps * _gst_caps_none;
144 * A flags word containing #GstCapsFlags flags set on this caps.
146 #define GST_CAPS_FLAGS(caps) GST_MINI_OBJECT_FLAGS(caps)
153 * Get access to the reference count field of the caps
155 #define GST_CAPS_REFCOUNT(caps) GST_MINI_OBJECT_REFCOUNT(caps)
157 * GST_CAPS_REFCOUNT_VALUE:
160 * Get the reference count value of the caps.
162 #define GST_CAPS_REFCOUNT_VALUE(caps) GST_MINI_OBJECT_REFCOUNT_VALUE(caps)
165 * GST_CAPS_FLAG_IS_SET:
167 * @flag: the #GstCapsFlags to check.
169 * Gives the status of a specific flag on a caps.
171 #define GST_CAPS_FLAG_IS_SET(caps,flag) GST_MINI_OBJECT_FLAG_IS_SET (caps, flag)
175 * @flag: the #GstCapsFlags to set.
177 * Sets a caps flag on a caps.
179 #define GST_CAPS_FLAG_SET(caps,flag) GST_MINI_OBJECT_FLAG_SET (caps, flag)
181 * GST_CAPS_FLAG_UNSET:
183 * @flag: the #GstCapsFlags to clear.
185 * Clears a caps flag.
187 #define GST_CAPS_FLAG_UNSET(caps,flag) GST_MINI_OBJECT_FLAG_UNSET (caps, flag)
192 * @caps: the #GstCaps to reference
194 * Add a reference to a #GstCaps object.
196 * From this point on, until the caller calls gst_caps_unref() or
197 * gst_caps_make_writable(), it is guaranteed that the caps object will not
198 * change. This means its structures won't change, etc. To use a #GstCaps
199 * object, you must always have a refcount on it -- either the one made
200 * implicitly by e.g. gst_caps_new_simple(), or via taking one explicitly with
203 * Returns: the same #GstCaps object.
205 #ifdef _FOOL_GTK_DOC_
206 G_INLINE_FUNC GstCaps * gst_caps_ref (GstCaps * caps);
209 static inline GstCaps *
210 gst_caps_ref (GstCaps * caps)
212 return (GstCaps *) gst_mini_object_ref (GST_MINI_OBJECT_CAST (caps));
219 * Unref a #GstCaps and and free all its structures and the
220 * structures' values when the refcount reaches 0.
222 #ifdef _FOOL_GTK_DOC_
223 G_INLINE_FUNC void gst_caps_unref (GstCaps * caps);
227 gst_caps_unref (GstCaps * caps)
229 gst_mini_object_unref (GST_MINI_OBJECT_CAST (caps));
237 * Creates a new #GstCaps as a copy of the old @caps. The new caps will have a
238 * refcount of 1, owned by the caller. The structures are copied as well.
240 * Note that this function is the semantic equivalent of a gst_caps_ref()
241 * followed by a gst_caps_make_writable(). If you only want to hold on to a
242 * reference to the data, you should use gst_caps_ref().
244 * When you are finished with the caps, call gst_caps_unref() on it.
246 * Returns: the new #GstCaps
248 #ifdef _FOOL_GTK_DOC_
249 G_INLINE_FUNC GstCaps * gst_caps_copy (const GstCaps * caps);
252 static inline GstCaps *
253 gst_caps_copy (const GstCaps * caps)
255 return GST_CAPS (gst_mini_object_copy (GST_MINI_OBJECT_CAST (caps)));
259 * gst_caps_is_writable:
262 * Tests if you can safely modify @caps. It is only safe to modify caps when
263 * there is only one owner of the caps - ie, the object is writable.
265 #define gst_caps_is_writable(caps) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (caps))
268 * gst_caps_make_writable:
269 * @caps: (transfer full): a #GstCaps
271 * Returns a writable copy of @caps.
273 * If there is only one reference count on @caps, the caller must be the owner,
274 * and so this function will return the caps object unchanged. If on the other
275 * hand there is more than one reference on the object, a new caps object will
276 * be returned. The caller's reference on @caps will be removed, and instead the
277 * caller will own a reference to the returned object.
279 * In short, this function unrefs the caps in the argument and refs the caps
280 * that it returns. Don't access the argument after calling this function. See
281 * also: gst_caps_ref().
283 * Returns: (transfer full): a writable caps which may or may not be the
286 #define gst_caps_make_writable(caps) GST_CAPS_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (caps)))
290 * @old_caps: (inout) (transfer full): pointer to a pointer to a #GstCaps to be
292 * @new_caps: (transfer none) (allow-none): pointer to a #GstCaps that will
293 * replace the caps pointed to by @ocaps.
295 * Modifies a pointer to a #GstCaps to point to a different #GstCaps. The
296 * modification is done atomically (so this is useful for ensuring thread safety
297 * in some cases), and the reference counts are updated appropriately (the old
298 * caps is unreffed, the new is reffed).
300 * Either @ncaps or the #GstCaps pointed to by @ocaps may be NULL.
302 * Returns: TRUE if @new_caps was different from @old_caps
304 #ifdef _FOOL_GTK_DOC_
305 G_INLINE_FUNC gboolean gst_caps_replace (GstCaps **old_caps, GstCaps *new_caps);
308 static inline gboolean
309 gst_caps_replace (GstCaps **old_caps, GstCaps *new_caps)
311 return gst_mini_object_replace ((GstMiniObject **) old_caps, (GstMiniObject *) new_caps);
316 * @old_caps: (inout) (transfer full): pointer to a pointer to a #GstCaps to be
318 * @new_caps: (transfer full) (allow-none): pointer to a #GstCaps that will
319 * replace the caps pointed to by @ocaps.
321 * Modifies a pointer to a #GstCaps to point to a different #GstCaps. This
322 * function is similar to gst_caps_replace() except that it takes ownership
325 * Returns: TRUE if @new_caps was different from @old_caps
327 #ifdef _FOOL_GTK_DOC_
328 G_INLINE_FUNC gboolean gst_caps_take (GstCaps **old_caps, GstCaps *new_caps);
331 static inline gboolean
332 gst_caps_take (GstCaps **old_caps, GstCaps *new_caps)
334 return gst_mini_object_take ((GstMiniObject **) old_caps, (GstMiniObject *) new_caps);
339 * @mini_object: the parent type
341 * Object describing media types.
344 GstMiniObject mini_object;
349 * @caps: the cached #GstCaps
350 * @string: a string describing a caps
352 * Datastructure to initialize #GstCaps from a string description usually
353 * used in conjunction with GST_STATIC_CAPS() and gst_static_caps_get() to
354 * instantiate a #GstCaps.
356 struct _GstStaticCaps {
362 gpointer _gst_reserved[GST_PADDING];
365 GType gst_caps_get_type (void);
367 GstCaps * gst_caps_new_empty (void);
368 GstCaps * gst_caps_new_any (void);
369 GstCaps * gst_caps_new_empty_simple (const char *media_type) G_GNUC_WARN_UNUSED_RESULT;
370 GstCaps * gst_caps_new_simple (const char *media_type,
371 const char *fieldname,
372 ...) G_GNUC_NULL_TERMINATED G_GNUC_WARN_UNUSED_RESULT;
373 GstCaps * gst_caps_new_full (GstStructure *struct1,
374 ...) G_GNUC_NULL_TERMINATED G_GNUC_WARN_UNUSED_RESULT;
375 GstCaps * gst_caps_new_full_valist (GstStructure *structure,
376 va_list var_args) G_GNUC_WARN_UNUSED_RESULT;
378 GType gst_static_caps_get_type (void);
379 GstCaps * gst_static_caps_get (GstStaticCaps *static_caps);
380 void gst_static_caps_cleanup (GstStaticCaps *static_caps);
383 void gst_caps_append (GstCaps *caps1,
385 void gst_caps_append_structure (GstCaps *caps,
386 GstStructure *structure);
387 void gst_caps_remove_structure (GstCaps *caps, guint idx);
388 GstCaps * gst_caps_merge (GstCaps *caps1,
389 GstCaps *caps2) G_GNUC_WARN_UNUSED_RESULT;
390 GstCaps * gst_caps_merge_structure (GstCaps *caps,
391 GstStructure *structure) G_GNUC_WARN_UNUSED_RESULT;
392 guint gst_caps_get_size (const GstCaps *caps);
393 GstStructure * gst_caps_get_structure (const GstCaps *caps,
395 GstStructure * gst_caps_steal_structure (GstCaps *caps,
396 guint index) G_GNUC_WARN_UNUSED_RESULT;
397 GstCaps * gst_caps_copy_nth (const GstCaps *caps, guint nth) G_GNUC_WARN_UNUSED_RESULT;
398 GstCaps * gst_caps_truncate (GstCaps *caps) G_GNUC_WARN_UNUSED_RESULT;
399 void gst_caps_set_value (GstCaps *caps,
401 const GValue *value);
402 void gst_caps_set_simple (GstCaps *caps,
403 const char *field, ...) G_GNUC_NULL_TERMINATED;
404 void gst_caps_set_simple_valist (GstCaps *caps,
409 gboolean gst_caps_is_any (const GstCaps *caps);
410 gboolean gst_caps_is_empty (const GstCaps *caps);
411 gboolean gst_caps_is_fixed (const GstCaps *caps);
412 gboolean gst_caps_is_always_compatible (const GstCaps *caps1,
413 const GstCaps *caps2);
414 gboolean gst_caps_is_subset (const GstCaps *subset,
415 const GstCaps *superset);
416 gboolean gst_caps_is_subset_structure (const GstCaps *caps,
417 const GstStructure *structure);
418 gboolean gst_caps_is_equal (const GstCaps *caps1,
419 const GstCaps *caps2);
420 gboolean gst_caps_is_equal_fixed (const GstCaps *caps1,
421 const GstCaps *caps2);
422 gboolean gst_caps_can_intersect (const GstCaps * caps1,
423 const GstCaps * caps2);
424 gboolean gst_caps_is_strictly_equal (const GstCaps *caps1,
425 const GstCaps *caps2);
429 GstCaps * gst_caps_intersect (GstCaps *caps1,
430 GstCaps *caps2) G_GNUC_WARN_UNUSED_RESULT;
431 GstCaps * gst_caps_intersect_full (GstCaps *caps1,
433 GstCapsIntersectMode mode) G_GNUC_WARN_UNUSED_RESULT;
434 GstCaps * gst_caps_subtract (GstCaps *minuend,
435 GstCaps *subtrahend) G_GNUC_WARN_UNUSED_RESULT;
436 GstCaps * gst_caps_normalize (GstCaps *caps) G_GNUC_WARN_UNUSED_RESULT;
437 GstCaps * gst_caps_simplify (GstCaps *caps) G_GNUC_WARN_UNUSED_RESULT;
439 GstCaps * gst_caps_fixate (GstCaps *caps) G_GNUC_WARN_UNUSED_RESULT;
442 gchar * gst_caps_to_string (const GstCaps *caps) G_GNUC_MALLOC;
443 GstCaps * gst_caps_from_string (const gchar *string) G_GNUC_WARN_UNUSED_RESULT;
447 #endif /* __GST_CAPS_H__ */