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.
22 * @short_description: Structure describing sets of media formats
23 * @see_also: #GstStructure
25 * Caps (capabilities) are lighweight refcounted objects describing media types.
26 * They are composed of an array of #GstStructure.
28 * Caps are exposed on #GstPadTemplate to describe all possible types a
29 * given pad can handle. They are also stored in the #GstRegistry along with
30 * a description of the #GstElement.
32 * Caps are exposed on the element pads using the gst_pad_get_caps() pad
33 * function. This function describes the possible types that the pad can
34 * handle or produce at runtime.
36 * Caps are also attached to buffers to describe to content of the data
37 * pointed to by the buffer with gst_buffer_set_caps(). Caps attached to
38 * a #GstBuffer allow for format negotiation upstream and downstream.
40 * A #GstCaps can be constructed with the following code fragment:
43 * <title>Creating caps</title>
46 * caps = gst_caps_new_simple ("video/x-raw-yuv",
47 * "format", GST_TYPE_FOURCC, GST_MAKE_FOURCC ('I', '4', '2', '0'),
48 * "framerate", GST_TYPE_FRACTION, 25, 1,
49 * "pixel-aspect-ratio", GST_TYPE_FRACTION, 1, 1,
50 * "width", G_TYPE_INT, 320,
51 * "height", G_TYPE_INT, 240,
56 * A #GstCaps is fixed when it has no properties with ranges or lists. Use
57 * gst_caps_is_fixed() to test for fixed caps. Only fixed caps can be
58 * set on a #GstPad or #GstBuffer.
60 * Various methods exist to work with the media types such as subtracting
63 * Last reviewed on 2007-02-13 (0.10.10)
72 #include "gst_private.h"
75 #define DEBUG_REFCOUNT
77 #define CAPS_POISON(caps) G_STMT_START{ \
79 GstCaps *_newcaps = gst_caps_copy (caps); \
80 gst_caps_unref(caps); \
84 #define STRUCTURE_POISON(structure) G_STMT_START{ \
86 GstStructure *_newstruct = gst_structure_copy (structure); \
87 gst_structure_free(structure); \
88 structure = _newstruct; \
91 #define IS_WRITABLE(caps) \
92 (g_atomic_int_get (&(caps)->refcount) == 1)
94 /* quick way to get a caps structure at an index without doing a type or array
96 #define gst_caps_get_structure_unchecked(caps, index) \
97 ((GstStructure *)g_ptr_array_index ((caps)->structs, (index)))
100 /* lock to protect multiple invocations of static caps to caps conversion */
101 G_LOCK_DEFINE_STATIC (static_caps_lock);
103 static void gst_caps_transform_to_string (const GValue * src_value,
104 GValue * dest_value);
105 static gboolean gst_caps_from_string_inplace (GstCaps * caps,
106 const gchar * string);
107 static GstCaps *gst_caps_copy_conditional (GstCaps * src);
110 gst_caps_get_type (void)
112 static GType gst_caps_type = 0;
114 if (G_UNLIKELY (gst_caps_type == 0)) {
115 gst_caps_type = g_boxed_type_register_static ("GstCaps",
116 (GBoxedCopyFunc) gst_caps_copy_conditional,
117 (GBoxedFreeFunc) gst_caps_unref);
119 g_value_register_transform_func (gst_caps_type,
120 G_TYPE_STRING, gst_caps_transform_to_string);
123 return gst_caps_type;
126 /* creation/deletion */
129 * gst_caps_new_empty:
131 * Creates a new #GstCaps that is empty. That is, the returned
132 * #GstCaps contains no media formats.
133 * Caller is responsible for unreffing the returned caps.
135 * Returns: the new #GstCaps
138 gst_caps_new_empty (void)
140 GstCaps *caps = g_slice_new (GstCaps);
142 caps->type = GST_TYPE_CAPS;
145 caps->structs = g_ptr_array_new ();
146 /* the 32 has been determined by logging caps sizes in _gst_caps_free
147 * but g_ptr_array uses 16 anyway if it expands once, so this does not help
149 * caps->structs = g_ptr_array_sized_new (32);
152 #ifdef DEBUG_REFCOUNT
153 GST_CAT_LOG (GST_CAT_CAPS, "created caps %p", caps);
162 * Creates a new #GstCaps that indicates that it is compatible with
165 * Returns: the new #GstCaps
168 gst_caps_new_any (void)
170 GstCaps *caps = gst_caps_new_empty ();
172 caps->flags = GST_CAPS_FLAGS_ANY;
178 * gst_caps_new_simple:
179 * @media_type: the media type of the structure
180 * @fieldname: first field to set
181 * @...: additional arguments
183 * Creates a new #GstCaps that contains one #GstStructure. The
184 * structure is defined by the arguments, which have the same format
185 * as gst_structure_new().
186 * Caller is responsible for unreffing the returned caps.
188 * Returns: the new #GstCaps
191 gst_caps_new_simple (const char *media_type, const char *fieldname, ...)
194 GstStructure *structure;
197 caps = gst_caps_new_empty ();
199 va_start (var_args, fieldname);
200 structure = gst_structure_new_valist (media_type, fieldname, var_args);
203 gst_caps_append_structure (caps, structure);
210 * @struct1: the first structure to add
211 * @...: additional structures to add
213 * Creates a new #GstCaps and adds all the structures listed as
214 * arguments. The list must be NULL-terminated. The structures
215 * are not copied; the returned #GstCaps owns the structures.
217 * Returns: the new #GstCaps
220 gst_caps_new_full (GstStructure * struct1, ...)
225 va_start (var_args, struct1);
226 caps = gst_caps_new_full_valist (struct1, var_args);
233 * gst_caps_new_full_valist:
234 * @structure: the first structure to add
235 * @var_args: additional structures to add
237 * Creates a new #GstCaps and adds all the structures listed as
238 * arguments. The list must be NULL-terminated. The structures
239 * are not copied; the returned #GstCaps owns the structures.
241 * Returns: the new #GstCaps
244 gst_caps_new_full_valist (GstStructure * structure, va_list var_args)
248 caps = gst_caps_new_empty ();
251 gst_caps_append_structure (caps, structure);
252 structure = va_arg (var_args, GstStructure *);
260 * @caps: the #GstCaps to copy
262 * Creates a new #GstCaps as a copy of the old @caps. The new caps will have a
263 * refcount of 1, owned by the caller. The structures are copied as well.
265 * Note that this function is the semantic equivalent of a gst_caps_ref()
266 * followed by a gst_caps_make_writable(). If you only want to hold on to a
267 * reference to the data, you should use gst_caps_ref().
269 * When you are finished with the caps, call gst_caps_unref() on it.
271 * Returns: the new #GstCaps
274 gst_caps_copy (const GstCaps * caps)
277 GstStructure *structure;
280 g_return_val_if_fail (GST_IS_CAPS (caps), NULL);
282 newcaps = gst_caps_new_empty ();
283 newcaps->flags = caps->flags;
284 n = caps->structs->len;
286 for (i = 0; i < n; i++) {
287 structure = gst_caps_get_structure_unchecked (caps, i);
288 gst_caps_append_structure (newcaps, gst_structure_copy (structure));
295 _gst_caps_free (GstCaps * caps)
297 GstStructure *structure;
300 /* The refcount must be 0, but since we're only called by gst_caps_unref,
301 * don't bother testing. */
302 len = caps->structs->len;
303 /* This can be used to get statistics about caps sizes */
304 /*GST_CAT_INFO (GST_CAT_CAPS, "caps size: %d", len); */
305 for (i = 0; i < len; i++) {
306 structure = (GstStructure *) gst_caps_get_structure_unchecked (caps, i);
307 gst_structure_set_parent_refcount (structure, NULL);
308 gst_structure_free (structure);
310 g_ptr_array_free (caps->structs, TRUE);
312 memset (caps, 0xff, sizeof (GstCaps));
315 #ifdef DEBUG_REFCOUNT
316 GST_CAT_LOG (GST_CAT_CAPS, "freeing caps %p", caps);
318 g_slice_free (GstCaps, caps);
322 * gst_caps_make_writable:
323 * @caps: the #GstCaps to make writable
325 * Returns a writable copy of @caps.
327 * If there is only one reference count on @caps, the caller must be the owner,
328 * and so this function will return the caps object unchanged. If on the other
329 * hand there is more than one reference on the object, a new caps object will
330 * be returned. The caller's reference on @caps will be removed, and instead the
331 * caller will own a reference to the returned object.
333 * In short, this function unrefs the caps in the argument and refs the caps
334 * that it returns. Don't access the argument after calling this function. See
335 * also: gst_caps_ref().
337 * Returns: the same #GstCaps object.
340 gst_caps_make_writable (GstCaps * caps)
344 g_return_val_if_fail (caps != NULL, NULL);
346 /* we are the only instance reffing this caps */
347 if (g_atomic_int_get (&caps->refcount) == 1)
351 copy = gst_caps_copy (caps);
352 gst_caps_unref (caps);
359 * @caps: the #GstCaps to reference
361 * Add a reference to a #GstCaps object.
363 * From this point on, until the caller calls gst_caps_unref() or
364 * gst_caps_make_writable(), it is guaranteed that the caps object will not
365 * change. This means its structures won't change, etc. To use a #GstCaps
366 * object, you must always have a refcount on it -- either the one made
367 * implicitly by gst_caps_new(), or via taking one explicitly with this
370 * Returns: the same #GstCaps object.
373 gst_caps_ref (GstCaps * caps)
375 g_return_val_if_fail (caps != NULL, NULL);
377 #ifdef DEBUG_REFCOUNT
378 GST_CAT_LOG (GST_CAT_REFCOUNTING, "%p %d->%d", caps,
379 GST_CAPS_REFCOUNT_VALUE (caps), GST_CAPS_REFCOUNT_VALUE (caps) + 1);
381 g_return_val_if_fail (GST_CAPS_REFCOUNT_VALUE (caps) > 0, NULL);
383 g_atomic_int_inc (&caps->refcount);
390 * @caps: the #GstCaps to unref
392 * Unref a #GstCaps and and free all its structures and the
393 * structures' values when the refcount reaches 0.
396 gst_caps_unref (GstCaps * caps)
398 g_return_if_fail (caps != NULL);
400 #ifdef DEBUG_REFCOUNT
401 GST_CAT_LOG (GST_CAT_REFCOUNTING, "%p %d->%d", caps,
402 GST_CAPS_REFCOUNT_VALUE (caps), GST_CAPS_REFCOUNT_VALUE (caps) - 1);
405 g_return_if_fail (GST_CAPS_REFCOUNT_VALUE (caps) > 0);
407 /* if we ended up with the refcount at zero, free the caps */
408 if (G_UNLIKELY (g_atomic_int_dec_and_test (&caps->refcount)))
409 _gst_caps_free (caps);
413 gst_static_caps_get_type (void)
415 static GType staticcaps_type = 0;
417 if (G_UNLIKELY (staticcaps_type == 0)) {
418 staticcaps_type = g_pointer_type_register_static ("GstStaticCaps");
420 return staticcaps_type;
425 * gst_static_caps_get:
426 * @static_caps: the #GstStaticCaps to convert
428 * Converts a #GstStaticCaps to a #GstCaps.
430 * Returns: A pointer to the #GstCaps. Unref after usage. Since the
431 * core holds an additional ref to the returned caps,
432 * use gst_caps_make_writable() on the returned caps to modify it.
435 gst_static_caps_get (GstStaticCaps * static_caps)
439 g_return_val_if_fail (static_caps != NULL, NULL);
441 caps = (GstCaps *) static_caps;
443 /* refcount is 0 when we need to convert */
444 if (G_UNLIKELY (g_atomic_int_get (&caps->refcount) == 0)) {
448 G_LOCK (static_caps_lock);
449 /* check if other thread already updated */
450 if (G_UNLIKELY (g_atomic_int_get (&caps->refcount) > 0))
453 string = static_caps->string;
455 if (G_UNLIKELY (string == NULL))
458 GST_CAT_LOG (GST_CAT_CAPS, "creating %p", static_caps);
460 /* we construct the caps on the stack, then copy over the struct into our
461 * real caps, refcount last. We do this because we must leave the refcount
462 * of the result caps to 0 so that other threads don't run away with the
463 * caps while we are constructing it. */
464 temp.type = GST_TYPE_CAPS;
466 temp.structs = g_ptr_array_new ();
468 /* initialize the caps to a refcount of 1 so the caps can be writable for
469 * the next statement */
472 /* convert to string */
473 if (G_UNLIKELY (!gst_caps_from_string_inplace (&temp, string)))
474 g_critical ("Could not convert static caps \"%s\"", string);
476 /* now copy stuff over to the real caps. */
477 caps->type = temp.type;
478 caps->flags = temp.flags;
479 caps->structs = temp.structs;
480 /* and bump the refcount so other threads can now read */
481 g_atomic_int_set (&caps->refcount, 1);
483 GST_CAT_LOG (GST_CAT_CAPS, "created %p", static_caps);
485 G_UNLOCK (static_caps_lock);
487 /* ref the caps, makes it not writable */
495 G_UNLOCK (static_caps_lock);
496 g_warning ("static caps %p string is NULL", static_caps);
502 static GstStructure *
503 gst_caps_remove_and_get_structure (GstCaps * caps, guint idx)
505 /* don't use index_fast, gst_caps_do_simplify relies on the order */
506 GstStructure *s = g_ptr_array_remove_index (caps->structs, idx);
508 gst_structure_set_parent_refcount (s, NULL);
513 gst_structure_is_equal_foreach (GQuark field_id, const GValue * val2,
516 GstStructure *struct1 = (GstStructure *) data;
517 const GValue *val1 = gst_structure_id_get_value (struct1, field_id);
519 if (G_UNLIKELY (val1 == NULL))
521 if (gst_value_compare (val1, val2) == GST_VALUE_EQUAL) {
529 gst_caps_structure_is_subset_field (GQuark field_id, const GValue * value,
532 GstStructure *subtract_from = user_data;
533 GValue subtraction = { 0, };
536 if (!(other = gst_structure_id_get_value (subtract_from, field_id)))
537 /* field is missing in one set */
540 /* equal values are subset */
541 if (gst_value_compare (other, value) == GST_VALUE_EQUAL)
549 * -> 1 - [1,2] = empty
553 * -> [1,2] - [1,3] = empty
557 * -> {1,3} - {1,2} = 3
560 * First caps subtraction needs to return a non-empty set, second
561 * subtractions needs to give en empty set.
563 if (gst_value_subtract (&subtraction, other, value)) {
564 g_value_unset (&subtraction);
565 /* !empty result, swapping must be empty */
566 if (!gst_value_subtract (&subtraction, value, other))
569 g_value_unset (&subtraction);
575 gst_caps_structure_is_subset (const GstStructure * minuend,
576 const GstStructure * subtrahend)
578 if ((minuend->name != subtrahend->name) ||
579 (gst_structure_n_fields (minuend) !=
580 gst_structure_n_fields (subtrahend))) {
584 return gst_structure_foreach ((GstStructure *) subtrahend,
585 gst_caps_structure_is_subset_field, (gpointer) minuend);
590 * @caps1: the #GstCaps that will be appended to
591 * @caps2: the #GstCaps to append
593 * Appends the structures contained in @caps2 to @caps1. The structures in
594 * @caps2 are not copied -- they are transferred to @caps1, and then @caps2 is
595 * freed. If either caps is ANY, the resulting caps will be ANY.
598 gst_caps_append (GstCaps * caps1, GstCaps * caps2)
600 GstStructure *structure;
603 g_return_if_fail (GST_IS_CAPS (caps1));
604 g_return_if_fail (GST_IS_CAPS (caps2));
605 g_return_if_fail (IS_WRITABLE (caps1));
606 g_return_if_fail (IS_WRITABLE (caps2));
611 if (G_UNLIKELY (gst_caps_is_any (caps1) || gst_caps_is_any (caps2))) {
612 /* FIXME: this leaks */
613 caps1->flags |= GST_CAPS_FLAGS_ANY;
614 for (i = caps2->structs->len - 1; i >= 0; i--) {
615 structure = gst_caps_remove_and_get_structure (caps2, i);
616 gst_structure_free (structure);
619 for (i = caps2->structs->len; i; i--) {
620 structure = gst_caps_remove_and_get_structure (caps2, 0);
621 gst_caps_append_structure (caps1, structure);
624 gst_caps_unref (caps2); /* guaranteed to free it */
629 * @caps1: the #GstCaps that will take the new entries
630 * @caps2: the #GstCaps to merge in
632 * Appends the structures contained in @caps2 to @caps1 if they are not yet
633 * expressed by @caps1. The structures in @caps2 are not copied -- they are
634 * transferred to @caps1, and then @caps2 is freed.
635 * If either caps is ANY, the resulting caps will be ANY.
640 gst_caps_merge (GstCaps * caps1, GstCaps * caps2)
642 GstStructure *structure;
645 g_return_if_fail (GST_IS_CAPS (caps1));
646 g_return_if_fail (GST_IS_CAPS (caps2));
647 g_return_if_fail (IS_WRITABLE (caps1));
648 g_return_if_fail (IS_WRITABLE (caps2));
653 if (G_UNLIKELY (gst_caps_is_any (caps1))) {
654 for (i = caps2->structs->len - 1; i >= 0; i--) {
655 structure = gst_caps_remove_and_get_structure (caps2, i);
656 gst_structure_free (structure);
658 } else if (G_UNLIKELY (gst_caps_is_any (caps2))) {
659 caps1->flags |= GST_CAPS_FLAGS_ANY;
660 for (i = caps1->structs->len - 1; i >= 0; i--) {
661 structure = gst_caps_remove_and_get_structure (caps1, i);
662 gst_structure_free (structure);
665 for (i = caps2->structs->len; i; i--) {
666 structure = gst_caps_remove_and_get_structure (caps2, 0);
667 gst_caps_merge_structure (caps1, structure);
670 GstCaps *com = gst_caps_intersect (caps1, caps2);
671 GstCaps *add = gst_caps_subtract (caps2, com);
673 GST_DEBUG ("common : %d", gst_caps_get_size (com));
674 GST_DEBUG ("adding : %d", gst_caps_get_size (add));
675 gst_caps_append (caps1, add);
676 gst_caps_unref (com);
679 gst_caps_unref (caps2); /* guaranteed to free it */
683 * gst_caps_append_structure:
684 * @caps: the #GstCaps that will be appended to
685 * @structure: the #GstStructure to append
687 * Appends @structure to @caps. The structure is not copied; @caps
688 * becomes the owner of @structure.
691 gst_caps_append_structure (GstCaps * caps, GstStructure * structure)
693 g_return_if_fail (GST_IS_CAPS (caps));
694 g_return_if_fail (IS_WRITABLE (caps));
696 if (G_LIKELY (structure)) {
697 g_return_if_fail (structure->parent_refcount == NULL);
700 STRUCTURE_POISON (structure);
703 gst_structure_set_parent_refcount (structure, &caps->refcount);
704 g_ptr_array_add (caps->structs, structure);
709 * gst_caps_remove_structure:
710 * @caps: the #GstCaps to remove from
711 * @idx: Index of the structure to remove
713 * removes the stucture with the given index from the list of structures
714 * contained in @caps.
717 gst_caps_remove_structure (GstCaps * caps, guint idx)
719 GstStructure *structure;
721 g_return_if_fail (caps != NULL);
722 g_return_if_fail (idx <= gst_caps_get_size (caps));
723 g_return_if_fail (IS_WRITABLE (caps));
725 structure = gst_caps_remove_and_get_structure (caps, idx);
726 gst_structure_free (structure);
730 * gst_caps_merge_structure:
731 * @caps: the #GstCaps that will the the new structure
732 * @structure: the #GstStructure to merge
734 * Appends @structure to @caps if its not already expressed by @caps. The
735 * structure is not copied; @caps becomes the owner of @structure.
738 gst_caps_merge_structure (GstCaps * caps, GstStructure * structure)
740 g_return_if_fail (GST_IS_CAPS (caps));
741 g_return_if_fail (IS_WRITABLE (caps));
743 if (G_LIKELY (structure)) {
744 GstStructure *structure1;
746 gboolean unique = TRUE;
748 g_return_if_fail (structure->parent_refcount == NULL);
751 STRUCTURE_POISON (structure);
754 /* check each structure */
755 for (i = caps->structs->len - 1; i >= 0; i--) {
756 structure1 = gst_caps_get_structure_unchecked (caps, i);
757 /* if structure is a subset of structure1, then skip it */
758 if (gst_caps_structure_is_subset (structure1, structure)) {
764 gst_structure_set_parent_refcount (structure, &caps->refcount);
765 g_ptr_array_add (caps->structs, structure);
767 gst_structure_free (structure);
777 * Gets the number of structures contained in @caps.
779 * Returns: the number of structures that @caps contains
782 gst_caps_get_size (const GstCaps * caps)
784 g_return_val_if_fail (GST_IS_CAPS (caps), 0);
786 return caps->structs->len;
790 * gst_caps_get_structure:
792 * @index: the index of the structure
794 * Finds the structure in @caps that has the index @index, and
797 * WARNING: This function takes a const GstCaps *, but returns a
798 * non-const GstStructure *. This is for programming convenience --
799 * the caller should be aware that structures inside a constant
800 * #GstCaps should not be modified. However, if you know the caps
801 * are writable, either because you have just copied them or made
802 * them writable with gst_caps_make_writable(), you may modify the
803 * structure returned in the usual way, e.g. with functions like
804 * gst_structure_set_simple().
806 * You do not need to free or unref the structure returned, it
807 * belongs to the #GstCaps.
809 * Returns: a pointer to the #GstStructure corresponding to @index
812 gst_caps_get_structure (const GstCaps * caps, guint index)
814 g_return_val_if_fail (GST_IS_CAPS (caps), NULL);
815 g_return_val_if_fail (index < caps->structs->len, NULL);
817 return gst_caps_get_structure_unchecked (caps, index);
822 * @caps: the #GstCaps to copy
823 * @nth: the nth structure to copy
825 * Creates a new #GstCaps and appends a copy of the nth structure
826 * contained in @caps.
828 * Returns: the new #GstCaps
831 gst_caps_copy_nth (const GstCaps * caps, guint nth)
834 GstStructure *structure;
836 g_return_val_if_fail (GST_IS_CAPS (caps), NULL);
838 newcaps = gst_caps_new_empty ();
839 newcaps->flags = caps->flags;
841 if (G_LIKELY (caps->structs->len > nth)) {
842 structure = gst_caps_get_structure_unchecked (caps, nth);
843 gst_caps_append_structure (newcaps, gst_structure_copy (structure));
851 * @caps: the #GstCaps to truncate
853 * Destructively discard all but the first structure from @caps. Useful when
854 * fixating. @caps must be writable.
857 gst_caps_truncate (GstCaps * caps)
861 g_return_if_fail (GST_IS_CAPS (caps));
862 g_return_if_fail (IS_WRITABLE (caps));
864 i = caps->structs->len - 1;
867 gst_caps_remove_structure (caps, i--);
871 * gst_caps_set_simple:
872 * @caps: the #GstCaps to set
873 * @field: first field to set
874 * @...: additional parameters
876 * Sets fields in a simple #GstCaps. A simple #GstCaps is one that
877 * only has one structure. The arguments must be passed in the same
878 * manner as gst_structure_set(), and be NULL-terminated.
881 gst_caps_set_simple (GstCaps * caps, const char *field, ...)
883 GstStructure *structure;
886 g_return_if_fail (GST_IS_CAPS (caps));
887 g_return_if_fail (caps->structs->len == 1);
888 g_return_if_fail (IS_WRITABLE (caps));
890 structure = gst_caps_get_structure_unchecked (caps, 0);
892 va_start (var_args, field);
893 gst_structure_set_valist (structure, field, var_args);
898 * gst_caps_set_simple_valist:
899 * @caps: the #GstCaps to copy
900 * @field: first field to set
901 * @varargs: additional parameters
903 * Sets fields in a simple #GstCaps. A simple #GstCaps is one that
904 * only has one structure. The arguments must be passed in the same
905 * manner as gst_structure_set(), and be NULL-terminated.
908 gst_caps_set_simple_valist (GstCaps * caps, const char *field, va_list varargs)
910 GstStructure *structure;
912 g_return_if_fail (GST_IS_CAPS (caps));
913 g_return_if_fail (caps->structs->len == 1);
914 g_return_if_fail (IS_WRITABLE (caps));
916 structure = gst_caps_get_structure_unchecked (caps, 0);
918 gst_structure_set_valist (structure, field, varargs);
925 * @caps: the #GstCaps to test
927 * Determines if @caps represents any media format.
929 * Returns: TRUE if @caps represents any format.
932 gst_caps_is_any (const GstCaps * caps)
934 g_return_val_if_fail (GST_IS_CAPS (caps), FALSE);
936 return (caps->flags & GST_CAPS_FLAGS_ANY);
941 * @caps: the #GstCaps to test
943 * Determines if @caps represents no media formats.
945 * Returns: TRUE if @caps represents no formats.
948 gst_caps_is_empty (const GstCaps * caps)
950 g_return_val_if_fail (GST_IS_CAPS (caps), FALSE);
952 if (caps->flags & GST_CAPS_FLAGS_ANY)
955 return (caps->structs == NULL) || (caps->structs->len == 0);
959 gst_caps_is_fixed_foreach (GQuark field_id, const GValue * value,
962 return gst_value_is_fixed (value);
967 * @caps: the #GstCaps to test
969 * Fixed #GstCaps describe exactly one format, that is, they have exactly
970 * one structure, and each field in the structure describes a fixed type.
971 * Examples of non-fixed types are GST_TYPE_INT_RANGE and GST_TYPE_LIST.
973 * Returns: TRUE if @caps is fixed
976 gst_caps_is_fixed (const GstCaps * caps)
978 GstStructure *structure;
980 g_return_val_if_fail (GST_IS_CAPS (caps), FALSE);
982 if (caps->structs->len != 1)
985 structure = gst_caps_get_structure_unchecked (caps, 0);
987 return gst_structure_foreach (structure, gst_caps_is_fixed_foreach, NULL);
991 * gst_caps_is_equal_fixed:
992 * @caps1: the #GstCaps to test
993 * @caps2: the #GstCaps to test
995 * Tests if two #GstCaps are equal. This function only works on fixed
998 * Returns: TRUE if the arguments represent the same format
1001 gst_caps_is_equal_fixed (const GstCaps * caps1, const GstCaps * caps2)
1003 GstStructure *struct1, *struct2;
1005 g_return_val_if_fail (gst_caps_is_fixed (caps1), FALSE);
1006 g_return_val_if_fail (gst_caps_is_fixed (caps2), FALSE);
1008 struct1 = gst_caps_get_structure_unchecked (caps1, 0);
1009 struct2 = gst_caps_get_structure_unchecked (caps2, 0);
1011 if (struct1->name != struct2->name) {
1014 if (struct1->fields->len != struct2->fields->len) {
1018 return gst_structure_foreach (struct1, gst_structure_is_equal_foreach,
1023 * gst_caps_is_always_compatible:
1024 * @caps1: the #GstCaps to test
1025 * @caps2: the #GstCaps to test
1027 * A given #GstCaps structure is always compatible with another if
1028 * every media format that is in the first is also contained in the
1029 * second. That is, @caps1 is a subset of @caps2.
1031 * Returns: TRUE if @caps1 is a subset of @caps2.
1034 gst_caps_is_always_compatible (const GstCaps * caps1, const GstCaps * caps2)
1036 g_return_val_if_fail (GST_IS_CAPS (caps1), FALSE);
1037 g_return_val_if_fail (GST_IS_CAPS (caps2), FALSE);
1039 return gst_caps_is_subset (caps1, caps2);
1043 * gst_caps_is_subset:
1044 * @subset: a #GstCaps
1045 * @superset: a potentially greater #GstCaps
1047 * Checks if all caps represented by @subset are also represented by @superset.
1048 * <note>This function does not work reliably if optional properties for caps
1049 * are included on one caps and omitted on the other.</note>
1051 * Returns: %TRUE if @subset is a subset of @superset
1054 gst_caps_is_subset (const GstCaps * subset, const GstCaps * superset)
1059 g_return_val_if_fail (subset != NULL, FALSE);
1060 g_return_val_if_fail (superset != NULL, FALSE);
1062 if (gst_caps_is_empty (subset) || gst_caps_is_any (superset))
1064 if (gst_caps_is_any (subset) || gst_caps_is_empty (superset))
1067 caps = gst_caps_subtract (subset, superset);
1068 ret = gst_caps_is_empty (caps);
1069 gst_caps_unref (caps);
1074 * gst_caps_is_equal:
1075 * @caps1: a #GstCaps
1076 * @caps2: another #GstCaps
1078 * Checks if the given caps represent the same set of caps.
1079 * <note>This function does not work reliably if optional properties for caps
1080 * are included on one caps and omitted on the other.</note>
1082 * This function deals correctly with passing NULL for any of the caps.
1084 * Returns: TRUE if both caps are equal.
1087 gst_caps_is_equal (const GstCaps * caps1, const GstCaps * caps2)
1089 /* FIXME 0.11: NULL pointers are no valid Caps but indicate an error
1090 * So there should be an assertion that caps1 and caps2 != NULL */
1092 /* NULL <-> NULL is allowed here */
1093 if (G_UNLIKELY (caps1 == caps2))
1096 /* one of them NULL => they are different (can't be both NULL because
1097 * we checked that above) */
1098 if (G_UNLIKELY (caps1 == NULL || caps2 == NULL))
1101 if (G_UNLIKELY (gst_caps_is_fixed (caps1) && gst_caps_is_fixed (caps2)))
1102 return gst_caps_is_equal_fixed (caps1, caps2);
1104 return gst_caps_is_subset (caps1, caps2) && gst_caps_is_subset (caps2, caps1);
1110 const GstStructure *intersect;
1116 gst_caps_structure_intersect_field (GQuark id, const GValue * val1,
1119 IntersectData *idata = (IntersectData *) data;
1120 GValue dest_value = { 0 };
1121 const GValue *val2 = gst_structure_id_get_value (idata->intersect, id);
1123 if (G_UNLIKELY (val2 == NULL)) {
1124 gst_structure_id_set_value (idata->dest, id, val1);
1125 } else if (idata->first_run) {
1126 if (gst_value_intersect (&dest_value, val1, val2)) {
1127 gst_structure_id_set_value (idata->dest, id, &dest_value);
1128 g_value_unset (&dest_value);
1137 static GstStructure *
1138 gst_caps_structure_intersect (const GstStructure * struct1,
1139 const GstStructure * struct2)
1143 g_return_val_if_fail (struct1 != NULL, NULL);
1144 g_return_val_if_fail (struct2 != NULL, NULL);
1146 if (G_UNLIKELY (struct1->name != struct2->name))
1149 data.dest = gst_structure_id_empty_new (struct1->name);
1150 data.intersect = struct2;
1151 data.first_run = TRUE;
1152 if (G_UNLIKELY (!gst_structure_foreach ((GstStructure *) struct1,
1153 gst_caps_structure_intersect_field, &data)))
1156 data.intersect = struct1;
1157 data.first_run = FALSE;
1158 if (G_UNLIKELY (!gst_structure_foreach ((GstStructure *) struct2,
1159 gst_caps_structure_intersect_field, &data)))
1165 gst_structure_free (data.dest);
1170 static GstStructure *
1171 gst_caps_structure_union (const GstStructure * struct1,
1172 const GstStructure * struct2)
1176 const GstStructureField *field1;
1177 const GstStructureField *field2;
1180 /* FIXME this doesn't actually work */
1182 if (struct1->name != struct2->name)
1185 dest = gst_structure_id_empty_new (struct1->name);
1187 for (i = 0; i < struct1->fields->len; i++) {
1188 GValue dest_value = { 0 };
1190 field1 = GST_STRUCTURE_FIELD (struct1, i);
1191 field2 = gst_structure_id_get_field (struct2, field1->name);
1193 if (field2 == NULL) {
1196 if (gst_value_union (&dest_value, &field1->value, &field2->value)) {
1197 gst_structure_set_value (dest, g_quark_to_string (field1->name),
1200 ret = gst_value_compare (&field1->value, &field2->value);
1212 * gst_caps_intersect:
1213 * @caps1: a #GstCaps to intersect
1214 * @caps2: a #GstCaps to intersect
1216 * Creates a new #GstCaps that contains all the formats that are common
1217 * to both @caps1 and @caps2.
1219 * Returns: the new #GstCaps
1222 gst_caps_intersect (const GstCaps * caps1, const GstCaps * caps2)
1224 guint64 i; /* index can be up to 2 * G_MAX_UINT */
1225 guint j, k, len1, len2;
1227 GstStructure *struct1;
1228 GstStructure *struct2;
1230 GstStructure *istruct;
1232 g_return_val_if_fail (GST_IS_CAPS (caps1), NULL);
1233 g_return_val_if_fail (GST_IS_CAPS (caps2), NULL);
1235 /* caps are exactly the same pointers, just copy one caps */
1236 if (G_UNLIKELY (caps1 == caps2))
1237 return gst_caps_copy (caps1);
1239 /* empty caps on either side, return empty */
1240 if (G_UNLIKELY (gst_caps_is_empty (caps1) || gst_caps_is_empty (caps2)))
1241 return gst_caps_new_empty ();
1243 /* one of the caps is any, just copy the other caps */
1244 if (G_UNLIKELY (gst_caps_is_any (caps1)))
1245 return gst_caps_copy (caps2);
1246 if (G_UNLIKELY (gst_caps_is_any (caps2)))
1247 return gst_caps_copy (caps1);
1249 dest = gst_caps_new_empty ();
1251 /* run zigzag on top line then right line, this preserves the caps order
1252 * much better than a simple loop.
1254 * This algorithm zigzags over the caps structures as demonstrated in
1255 * the folowing matrix:
1263 * First we iterate over the caps1 structures (top line) intersecting
1264 * the structures diagonally down, then we iterate over the caps2
1267 len1 = caps1->structs->len;
1268 len2 = caps2->structs->len;
1269 for (i = 0; i < len1 + len2 - 1; i++) {
1270 /* caps1 index goes from 0 to caps1->structs->len-1 */
1271 j = MIN (i, len1 - 1);
1272 /* caps2 index stays 0 until i reaches caps1->structs->len, then it counts
1273 * up from 1 to caps2->structs->len - 1 */
1276 /* now run the diagonal line, end condition is the left or bottom
1279 struct1 = gst_caps_get_structure_unchecked (caps1, j);
1280 struct2 = gst_caps_get_structure_unchecked (caps2, k);
1282 istruct = gst_caps_structure_intersect (struct1, struct2);
1284 gst_caps_append_structure (dest, istruct);
1285 /* move down left */
1287 if (G_UNLIKELY (j == 0))
1288 break; /* so we don't roll back to G_MAXUINT */
1297 const GstStructure *subtract_from;
1304 gst_caps_structure_subtract_field (GQuark field_id, const GValue * value,
1307 SubtractionEntry *e = user_data;
1308 GValue subtraction = { 0, };
1309 const GValue *other;
1310 GstStructure *structure;
1312 other = gst_structure_id_get_value (e->subtract_from, field_id);
1316 if (!gst_value_subtract (&subtraction, other, value))
1318 if (gst_value_compare (&subtraction, other) == GST_VALUE_EQUAL) {
1319 g_value_unset (&subtraction);
1322 structure = gst_structure_copy (e->subtract_from);
1323 gst_structure_id_set_value (structure, field_id, &subtraction);
1324 g_value_unset (&subtraction);
1325 e->put_into = g_slist_prepend (e->put_into, structure);
1331 gst_caps_structure_subtract (GSList ** into, const GstStructure * minuend,
1332 const GstStructure * subtrahend)
1337 e.subtract_from = minuend;
1340 ret = gst_structure_foreach ((GstStructure *) subtrahend,
1341 gst_caps_structure_subtract_field, &e);
1347 for (walk = e.put_into; walk; walk = g_slist_next (walk)) {
1348 gst_structure_free (walk->data);
1350 g_slist_free (e.put_into);
1356 * gst_caps_subtract:
1357 * @minuend: #GstCaps to substract from
1358 * @subtrahend: #GstCaps to substract
1360 * Subtracts the @subtrahend from the @minuend.
1361 * <note>This function does not work reliably if optional properties for caps
1362 * are included on one caps and omitted on the other.</note>
1364 * Returns: the resulting caps
1367 gst_caps_subtract (const GstCaps * minuend, const GstCaps * subtrahend)
1372 GstCaps *dest = NULL, *src;
1374 g_return_val_if_fail (minuend != NULL, NULL);
1375 g_return_val_if_fail (subtrahend != NULL, NULL);
1377 if (gst_caps_is_empty (minuend) || gst_caps_is_any (subtrahend)) {
1378 return gst_caps_new_empty ();
1380 if (gst_caps_is_empty (subtrahend))
1381 return gst_caps_copy (minuend);
1383 /* FIXME: Do we want this here or above?
1384 The reason we need this is that there is no definition about what
1385 ANY means for specific types, so it's not possible to reduce ANY partially
1386 You can only remove everything or nothing and that is done above.
1387 Note: there's a test that checks this behaviour. */
1388 g_return_val_if_fail (!gst_caps_is_any (minuend), NULL);
1389 sublen = subtrahend->structs->len;
1390 g_assert (sublen > 0);
1392 src = gst_caps_copy (minuend);
1393 for (i = 0; i < sublen; i++) {
1396 sub = gst_caps_get_structure_unchecked (subtrahend, i);
1398 gst_caps_unref (src);
1401 dest = gst_caps_new_empty ();
1402 srclen = src->structs->len;
1403 for (j = 0; j < srclen; j++) {
1404 min = gst_caps_get_structure_unchecked (src, j);
1405 if (gst_structure_get_name_id (min) == gst_structure_get_name_id (sub)) {
1408 if (gst_caps_structure_subtract (&list, min, sub)) {
1411 for (walk = list; walk; walk = g_slist_next (walk)) {
1412 gst_caps_append_structure (dest, (GstStructure *) walk->data);
1414 g_slist_free (list);
1416 gst_caps_append_structure (dest, gst_structure_copy (min));
1419 gst_caps_append_structure (dest, gst_structure_copy (min));
1422 if (gst_caps_is_empty (dest)) {
1423 gst_caps_unref (src);
1428 gst_caps_unref (src);
1429 gst_caps_do_simplify (dest);
1435 * @caps1: a #GstCaps to union
1436 * @caps2: a #GstCaps to union
1438 * Creates a new #GstCaps that contains all the formats that are in
1439 * either @caps1 and @caps2.
1441 * Returns: the new #GstCaps
1444 gst_caps_union (const GstCaps * caps1, const GstCaps * caps2)
1449 /* NULL pointers are no correct GstCaps */
1450 g_return_val_if_fail (caps1 != NULL, NULL);
1451 g_return_val_if_fail (caps2 != NULL, NULL);
1453 if (gst_caps_is_empty (caps1))
1454 return gst_caps_copy (caps2);
1456 if (gst_caps_is_empty (caps2))
1457 return gst_caps_copy (caps1);
1459 if (gst_caps_is_any (caps1) || gst_caps_is_any (caps2))
1460 return gst_caps_new_any ();
1462 dest1 = gst_caps_copy (caps1);
1463 dest2 = gst_caps_copy (caps2);
1464 gst_caps_append (dest1, dest2);
1466 gst_caps_do_simplify (dest1);
1470 typedef struct _NormalizeForeach
1473 GstStructure *structure;
1478 gst_caps_normalize_foreach (GQuark field_id, const GValue * value, gpointer ptr)
1480 NormalizeForeach *nf = (NormalizeForeach *) ptr;
1484 if (G_VALUE_TYPE (value) == GST_TYPE_LIST) {
1485 guint len = gst_value_list_get_size (value);
1486 for (i = 1; i < len; i++) {
1487 const GValue *v = gst_value_list_get_value (value, i);
1488 GstStructure *structure = gst_structure_copy (nf->structure);
1490 gst_structure_id_set_value (structure, field_id, v);
1491 gst_caps_append_structure (nf->caps, structure);
1494 gst_value_init_and_copy (&val, gst_value_list_get_value (value, 0));
1495 gst_structure_id_set_value (nf->structure, field_id, &val);
1496 g_value_unset (&val);
1504 * gst_caps_normalize:
1505 * @caps: a #GstCaps to normalize
1507 * Creates a new #GstCaps that represents the same set of formats as
1508 * @caps, but contains no lists. Each list is expanded into separate
1511 * Returns: the new #GstCaps
1514 gst_caps_normalize (const GstCaps * caps)
1516 NormalizeForeach nf;
1520 g_return_val_if_fail (GST_IS_CAPS (caps), NULL);
1522 newcaps = gst_caps_copy (caps);
1524 nlen = newcaps->structs->len;
1526 for (i = 0; i < nlen; i++) {
1527 nf.structure = gst_caps_get_structure_unchecked (newcaps, i);
1529 while (!gst_structure_foreach (nf.structure,
1530 gst_caps_normalize_foreach, &nf));
1537 gst_caps_compare_structures (gconstpointer one, gconstpointer two)
1540 const GstStructure *struct1 = *((const GstStructure **) one);
1541 const GstStructure *struct2 = *((const GstStructure **) two);
1543 /* FIXME: this orders alphabetically, but ordering the quarks might be faster
1544 So what's the best way? */
1545 ret = strcmp (gst_structure_get_name (struct1),
1546 gst_structure_get_name (struct2));
1550 return gst_structure_n_fields (struct2) - gst_structure_n_fields (struct1);
1557 GstStructure *compare;
1562 gst_caps_structure_figure_out_union (GQuark field_id, const GValue * value,
1565 UnionField *u = user_data;
1566 const GValue *val = gst_structure_id_get_value (u->compare, field_id);
1570 g_value_unset (&u->value);
1573 if (gst_value_compare (val, value) == GST_VALUE_EQUAL)
1576 g_value_unset (&u->value);
1580 gst_value_union (&u->value, val, value);
1585 gst_caps_structure_simplify (GstStructure ** result,
1586 const GstStructure * simplify, GstStructure * compare)
1589 UnionField field = { 0, {0,}, NULL };
1591 /* try to subtract to get a real subset */
1592 if (gst_caps_structure_subtract (&list, simplify, compare)) {
1593 switch (g_slist_length (list)) {
1598 *result = list->data;
1599 g_slist_free (list);
1605 for (walk = list; walk; walk = g_slist_next (walk)) {
1606 gst_structure_free (walk->data);
1608 g_slist_free (list);
1614 /* try to union both structs */
1615 field.compare = compare;
1616 if (gst_structure_foreach ((GstStructure *) simplify,
1617 gst_caps_structure_figure_out_union, &field)) {
1618 gboolean ret = FALSE;
1620 /* now we know all of simplify's fields are the same in compare
1621 * but at most one field: field.name */
1622 if (G_IS_VALUE (&field.value)) {
1623 if (gst_structure_n_fields (simplify) == gst_structure_n_fields (compare)) {
1624 gst_structure_id_set_value (compare, field.name, &field.value);
1628 g_value_unset (&field.value);
1629 } else if (gst_structure_n_fields (simplify) <=
1630 gst_structure_n_fields (compare)) {
1631 /* compare is just more specific, will be optimized away later */
1632 /* FIXME: do this here? */
1633 GST_LOG ("found a case that will be optimized later.");
1635 gchar *one = gst_structure_to_string (simplify);
1636 gchar *two = gst_structure_to_string (compare);
1639 ("caps mismatch: structures %s and %s claim to be possible to unify, but aren't",
1651 gst_caps_switch_structures (GstCaps * caps, GstStructure * old,
1652 GstStructure * new, gint i)
1654 gst_structure_set_parent_refcount (old, NULL);
1655 gst_structure_free (old);
1656 gst_structure_set_parent_refcount (new, &caps->refcount);
1657 g_ptr_array_index (caps->structs, i) = new;
1661 * gst_caps_do_simplify:
1662 * @caps: a #GstCaps to simplify
1664 * Modifies the given @caps inplace into a representation that represents the
1665 * same set of formats, but in a simpler form. Component structures that are
1666 * identical are merged. Component structures that have values that can be
1667 * merged are also merged.
1669 * Returns: TRUE, if the caps could be simplified
1672 gst_caps_do_simplify (GstCaps * caps)
1674 GstStructure *simplify, *compare, *result = NULL;
1676 gboolean changed = FALSE;
1678 g_return_val_if_fail (caps != NULL, FALSE);
1679 g_return_val_if_fail (IS_WRITABLE (caps), FALSE);
1681 if (gst_caps_get_size (caps) < 2)
1684 g_ptr_array_sort (caps->structs, gst_caps_compare_structures);
1686 start = caps->structs->len - 1;
1687 for (i = caps->structs->len - 1; i >= 0; i--) {
1688 simplify = gst_caps_get_structure_unchecked (caps, i);
1689 if (gst_structure_get_name_id (simplify) !=
1690 gst_structure_get_name_id (gst_caps_get_structure_unchecked (caps,
1693 for (j = start; j >= 0; j--) {
1696 compare = gst_caps_get_structure_unchecked (caps, j);
1697 if (gst_structure_get_name_id (simplify) !=
1698 gst_structure_get_name_id (compare)) {
1701 if (gst_caps_structure_simplify (&result, simplify, compare)) {
1703 gst_caps_switch_structures (caps, simplify, result, i);
1706 gst_caps_remove_structure (caps, i);
1718 /* gst_caps_do_simplify (caps); */
1722 #ifndef GST_DISABLE_LOADSAVE
1724 * gst_caps_save_thyself:
1725 * @caps: a #GstCaps structure
1726 * @parent: a XML parent node
1728 * Serializes a #GstCaps to XML and adds it as a child node of @parent.
1730 * Returns: a XML node pointer
1733 gst_caps_save_thyself (const GstCaps * caps, xmlNodePtr parent)
1735 char *s = gst_caps_to_string (caps);
1737 xmlNewChild (parent, NULL, (xmlChar *) "caps", (xmlChar *) s);
1743 * gst_caps_load_thyself:
1744 * @parent: a XML node
1746 * Creates a #GstCaps from its XML serialization.
1748 * Returns: a new #GstCaps structure
1751 gst_caps_load_thyself (xmlNodePtr parent)
1753 if (strcmp ("caps", (char *) parent->name) == 0) {
1754 return gst_caps_from_string ((gchar *) xmlNodeGetContent (parent));
1765 * @caps: a pointer to #GstCaps
1766 * @newcaps: a #GstCaps to replace *caps
1768 * Replaces *caps with @newcaps. Unrefs the #GstCaps in the location
1769 * pointed to by @caps, if applicable, then modifies @caps to point to
1770 * @newcaps. An additional ref on @newcaps is taken.
1772 * This function does not take any locks so you might want to lock
1773 * the object owning @caps pointer.
1776 gst_caps_replace (GstCaps ** caps, GstCaps * newcaps)
1780 g_return_if_fail (caps != NULL);
1784 GST_CAT_LOG (GST_CAT_REFCOUNTING, "%p, %p -> %p", caps, oldcaps, newcaps);
1786 if (newcaps != oldcaps) {
1788 gst_caps_ref (newcaps);
1793 gst_caps_unref (oldcaps);
1798 * gst_caps_to_string:
1801 * Converts @caps to a string representation. This string representation
1802 * can be converted back to a #GstCaps by gst_caps_from_string().
1804 * For debugging purposes its easier to do something like this:
1806 * GST_LOG ("caps are %" GST_PTR_FORMAT, caps);
1808 * This prints the caps in human readble form.
1810 * Returns: a newly allocated string representing @caps.
1813 gst_caps_to_string (const GstCaps * caps)
1815 guint i, slen, clen;
1818 /* NOTE: This function is potentially called by the debug system,
1819 * so any calls to gst_log() (and GST_DEBUG(), GST_LOG(), etc.)
1820 * should be careful to avoid recursion. This includes any functions
1821 * called by gst_caps_to_string. In particular, calls should
1822 * not use the GST_PTR_FORMAT extension. */
1825 return g_strdup ("NULL");
1827 if (gst_caps_is_any (caps)) {
1828 return g_strdup ("ANY");
1830 if (gst_caps_is_empty (caps)) {
1831 return g_strdup ("EMPTY");
1834 /* estimate a rough string length to avoid unnecessary reallocs in GString */
1836 clen = caps->structs->len;
1837 for (i = 0; i < clen; i++) {
1839 STRUCTURE_ESTIMATED_STRING_LEN (gst_caps_get_structure_unchecked (caps,
1843 s = g_string_sized_new (slen);
1844 for (i = 0; i < clen; i++) {
1845 GstStructure *structure;
1848 /* ';' is now added by gst_structure_to_string */
1849 g_string_append_c (s, ' ');
1852 structure = gst_caps_get_structure_unchecked (caps, i);
1853 priv_gst_structure_append_to_gstring (structure, s);
1855 if (s->len && s->str[s->len - 1] == ';') {
1856 /* remove latest ';' */
1857 s->str[--s->len] = '\0';
1859 return g_string_free (s, FALSE);
1863 gst_caps_from_string_inplace (GstCaps * caps, const gchar * string)
1865 GstStructure *structure;
1868 g_return_val_if_fail (string, FALSE);
1869 if (strcmp ("ANY", string) == 0) {
1870 caps->flags = GST_CAPS_FLAGS_ANY;
1873 if (strcmp ("EMPTY", string) == 0) {
1877 structure = gst_structure_from_string (string, &s);
1878 if (structure == NULL) {
1881 gst_caps_append_structure (caps, structure);
1885 while (g_ascii_isspace (*s))
1890 structure = gst_structure_from_string (s, &s);
1891 if (structure == NULL) {
1894 gst_caps_append_structure (caps, structure);
1902 * gst_caps_from_string:
1903 * @string: a string to convert to #GstCaps
1905 * Converts @caps from a string representation.
1907 * Returns: a newly allocated #GstCaps
1910 gst_caps_from_string (const gchar * string)
1914 caps = gst_caps_new_empty ();
1915 if (gst_caps_from_string_inplace (caps, string)) {
1918 gst_caps_unref (caps);
1924 gst_caps_transform_to_string (const GValue * src_value, GValue * dest_value)
1926 g_return_if_fail (G_IS_VALUE (src_value));
1927 g_return_if_fail (G_IS_VALUE (dest_value));
1928 g_return_if_fail (G_VALUE_HOLDS (src_value, GST_TYPE_CAPS));
1929 g_return_if_fail (G_VALUE_HOLDS (dest_value, G_TYPE_STRING)
1930 || G_VALUE_HOLDS (dest_value, G_TYPE_POINTER));
1932 dest_value->data[0].v_pointer =
1933 gst_caps_to_string (src_value->data[0].v_pointer);
1937 gst_caps_copy_conditional (GstCaps * src)
1940 return gst_caps_ref (src);