/**
* SECTION:gstcaps
* @short_description: Structure describing sets of media formats
- * @see_also: #GstStructure
+ * @see_also: #GstStructure, #GstMiniObject
*
- * Caps (capabilities) are lighweight refcounted objects describing media types.
+ * Caps (capabilities) are lightweight refcounted objects describing media types.
* They are composed of an array of #GstStructure.
*
* Caps are exposed on #GstPadTemplate to describe all possible types a
* function. This function describes the possible types that the pad can
* handle or produce at runtime.
*
- * Caps are also attached to buffers to describe to content of the data
- * pointed to by the buffer with gst_buffer_set_caps(). Caps attached to
- * a #GstBuffer allow for format negotiation upstream and downstream.
- *
* A #GstCaps can be constructed with the following code fragment:
*
* <example>
* </example>
*
* A #GstCaps is fixed when it has no properties with ranges or lists. Use
- * gst_caps_is_fixed() to test for fixed caps. Only fixed caps can be
- * set on a #GstPad or #GstBuffer.
+ * gst_caps_is_fixed() to test for fixed caps. Fixed caps can be used in a
+ * caps event to notify downstream elements of the current media type.
*
* Various methods exist to work with the media types such as subtracting
* or intersecting.
*
- * Last reviewed on 2007-02-13 (0.10.10)
+ * Last reviewed on 2011-03-28 (0.11.3)
*/
#ifdef HAVE_CONFIG_H
g_ptr_array_free (GST_CAPS_ARRAY (caps), TRUE);
#ifdef DEBUG_REFCOUNT
- GST_CAT_LOG (GST_CAT_CAPS, "freeing caps %p", caps);
+ GST_CAT_TRACE (GST_CAT_CAPS, "freeing caps %p", caps);
#endif
g_slice_free1 (GST_MINI_OBJECT_SIZE (caps), caps);
}
/* the 32 has been determined by logging caps sizes in _gst_caps_free
* but g_ptr_array uses 16 anyway if it expands once, so this does not help
- * in practise
+ * in practice
* GST_CAPS_ARRAY (caps) = g_ptr_array_sized_new (32);
*/
GST_CAPS_ARRAY (caps) = g_ptr_array_new ();
*
* Creates a new #GstCaps that is empty. That is, the returned
* #GstCaps contains no media formats.
+ * The #GstCaps is guaranteed to be writable.
* Caller is responsible for unreffing the returned caps.
*
* Returns: (transfer full): the new #GstCaps
static GstStructure *
gst_caps_remove_and_get_structure (GstCaps * caps, guint idx)
{
- /* don't use index_fast, gst_caps_do_simplify relies on the order */
+ /* don't use index_fast, gst_caps_simplify relies on the order */
GstStructure *s = g_ptr_array_remove_index (GST_CAPS_ARRAY (caps), idx);
gst_structure_set_parent_refcount (s, NULL);
* @caps: the #GstCaps to retrieve from
* @index: Index of the structure to retrieve
*
- * Retrieves the stucture with the given index from the list of structures
+ * Retrieves the structure with the given index from the list of structures
* contained in @caps. The caller becomes the owner of the returned structure.
*
* Returns: (transfer full): a pointer to the #GstStructure corresponding
g_return_if_fail (GST_IS_CAPS (caps2));
g_return_if_fail (IS_WRITABLE (caps1));
- caps2 = gst_caps_make_writable (caps2);
-
if (G_UNLIKELY (CAPS_IS_ANY (caps1) || CAPS_IS_ANY (caps2))) {
- /* FIXME: this leaks */
GST_CAPS_FLAGS (caps1) |= GST_CAPS_FLAG_ANY;
- for (i = GST_CAPS_LEN (caps2) - 1; i >= 0; i--) {
- structure = gst_caps_remove_and_get_structure (caps2, i);
- gst_structure_free (structure);
- }
+ gst_caps_unref (caps2);
} else {
+ caps2 = gst_caps_make_writable (caps2);
+
for (i = GST_CAPS_LEN (caps2); i; i--) {
structure = gst_caps_remove_and_get_structure (caps2, 0);
gst_caps_append_structure_unchecked (caps1, structure);
}
+ gst_caps_unref (caps2); /* guaranteed to free it */
}
- gst_caps_unref (caps2); /* guaranteed to free it */
}
/**
* gst_caps_merge:
- * @caps1: the #GstCaps that will take the new entries
+ * @caps1: (transfer full): the #GstCaps that will take the new entries
* @caps2: (transfer full): the #GstCaps to merge in
*
* Appends the structures contained in @caps2 to @caps1 if they are not yet
* expressed by @caps1. The structures in @caps2 are not copied -- they are
- * transferred to @caps1, and then @caps2 is freed.
+ * transferred to a writable copy of @caps1, and then @caps2 is freed.
* If either caps is ANY, the resulting caps will be ANY.
*
+ * Returns: (transfer full): the merged caps.
+ *
* Since: 0.10.10
*/
-void
+GstCaps *
gst_caps_merge (GstCaps * caps1, GstCaps * caps2)
{
GstStructure *structure;
int i;
+ GstCaps *result;
- g_return_if_fail (GST_IS_CAPS (caps1));
- g_return_if_fail (GST_IS_CAPS (caps2));
- g_return_if_fail (IS_WRITABLE (caps1));
-
- caps2 = gst_caps_make_writable (caps2);
+ g_return_val_if_fail (GST_IS_CAPS (caps1), NULL);
+ g_return_val_if_fail (GST_IS_CAPS (caps2), NULL);
if (G_UNLIKELY (CAPS_IS_ANY (caps1))) {
- for (i = GST_CAPS_LEN (caps2) - 1; i >= 0; i--) {
- structure = gst_caps_remove_and_get_structure (caps2, i);
- gst_structure_free (structure);
- }
+ gst_caps_unref (caps2);
+ result = caps1;
} else if (G_UNLIKELY (CAPS_IS_ANY (caps2))) {
- GST_CAPS_FLAGS (caps1) |= GST_CAPS_FLAG_ANY;
- for (i = GST_CAPS_LEN (caps1) - 1; i >= 0; i--) {
- structure = gst_caps_remove_and_get_structure (caps1, i);
- gst_structure_free (structure);
- }
+ gst_caps_unref (caps1);
+ result = caps2;
} else {
+ caps2 = gst_caps_make_writable (caps2);
+
for (i = GST_CAPS_LEN (caps2); i; i--) {
structure = gst_caps_remove_and_get_structure (caps2, 0);
- gst_caps_merge_structure (caps1, structure);
+ caps1 = gst_caps_merge_structure (caps1, structure);
}
+ gst_caps_unref (caps2);
+ result = caps1;
+
/* this is too naive
GstCaps *com = gst_caps_intersect (caps1, caps2);
GstCaps *add = gst_caps_subtract (caps2, com);
gst_caps_unref (com);
*/
}
- gst_caps_unref (caps2); /* guaranteed to free it */
+
+ return result;
}
/**
/**
* gst_caps_merge_structure:
- * @caps: the #GstCaps that will the new structure
+ * @caps: (transfer full): the #GstCaps to merge into
* @structure: (transfer full): the #GstStructure to merge
*
- * Appends @structure to @caps if its not already expressed by @caps. The
- * structure is not copied; @caps becomes the owner of @structure.
+ * Appends @structure to @caps if its not already expressed by @caps.
+ *
+ * Returns: (transfer full): the merged caps.
*/
-void
+GstCaps *
gst_caps_merge_structure (GstCaps * caps, GstStructure * structure)
{
- g_return_if_fail (GST_IS_CAPS (caps));
- g_return_if_fail (IS_WRITABLE (caps));
+ GstStructure *structure1;
+ int i;
+ gboolean unique = TRUE;
- if (G_LIKELY (structure)) {
- GstStructure *structure1;
- int i;
- gboolean unique = TRUE;
-
- /* check each structure */
- for (i = GST_CAPS_LEN (caps) - 1; i >= 0; i--) {
- structure1 = gst_caps_get_structure_unchecked (caps, i);
- /* if structure is a subset of structure1, then skip it */
- if (gst_structure_is_subset (structure, structure1)) {
- unique = FALSE;
- break;
- }
- }
- if (unique) {
- gst_caps_append_structure_unchecked (caps, structure);
- } else {
- gst_structure_free (structure);
+ g_return_val_if_fail (GST_IS_CAPS (caps), NULL);
+
+ if (G_UNLIKELY (structure == NULL))
+ return caps;
+
+ /* check each structure */
+ for (i = GST_CAPS_LEN (caps) - 1; i >= 0; i--) {
+ structure1 = gst_caps_get_structure_unchecked (caps, i);
+ /* if structure is a subset of structure1, then skip it */
+ if (gst_structure_is_subset (structure, structure1)) {
+ unique = FALSE;
+ break;
}
}
+ if (unique) {
+ caps = gst_caps_make_writable (caps);
+ gst_caps_append_structure_unchecked (caps, structure);
+ } else {
+ gst_structure_free (structure);
+ }
+ return caps;
}
/**
/**
* gst_caps_truncate:
- * @caps: the #GstCaps to truncate
+ * @caps: (transfer full): the #GstCaps to truncate
+ *
+ * Discard all but the first structure from @caps. Useful when
+ * fixating.
*
- * Destructively discard all but the first structure from @caps. Useful when
- * fixating. @caps must be writable.
+ * Returns: (transfer full): truncated caps
*/
-void
+GstCaps *
gst_caps_truncate (GstCaps * caps)
{
gint i;
- g_return_if_fail (GST_IS_CAPS (caps));
- g_return_if_fail (IS_WRITABLE (caps));
+ g_return_val_if_fail (GST_IS_CAPS (caps), NULL);
i = GST_CAPS_LEN (caps) - 1;
+ if (i == 0)
+ return caps;
+ caps = gst_caps_make_writable (caps);
while (i > 0)
gst_caps_remove_structure (caps, i--);
+
+ return caps;
}
/**
* <note>This function does not work reliably if optional properties for caps
* are included on one caps and omitted on the other.</note>
*
- * This function deals correctly with passing NULL for any of the caps.
- *
* Returns: TRUE if both caps are equal.
*/
gboolean
gst_caps_is_equal (const GstCaps * caps1, const GstCaps * caps2)
{
- /* FIXME 0.11: NULL pointers are no valid Caps but indicate an error
- * So there should be an assertion that caps1 and caps2 != NULL */
+ g_return_val_if_fail (GST_IS_CAPS (caps1), FALSE);
+ g_return_val_if_fail (GST_IS_CAPS (caps2), FALSE);
- /* NULL <-> NULL is allowed here */
if (G_UNLIKELY (caps1 == caps2))
return TRUE;
- /* one of them NULL => they are different (can't be both NULL because
- * we checked that above) */
- if (G_UNLIKELY (caps1 == NULL || caps2 == NULL))
- return FALSE;
-
if (G_UNLIKELY (gst_caps_is_fixed (caps1) && gst_caps_is_fixed (caps2)))
return gst_caps_is_equal_fixed (caps1, caps2);
gst_caps_is_strictly_equal (const GstCaps * caps1, const GstCaps * caps2)
{
int i;
- /* FIXME 0.11: NULL pointers are no valid Caps but indicate an error
- * So there should be an assertion that caps1 and caps2 != NULL */
- /* NULL <-> NULL is allowed here */
+ g_return_val_if_fail (GST_IS_CAPS (caps1), FALSE);
+ g_return_val_if_fail (GST_IS_CAPS (caps2), FALSE);
+
if (G_UNLIKELY (caps1 == caps2))
return TRUE;
- /* one of them NULL => they are different (can't be both NULL because
- * we checked that above) */
- if (G_UNLIKELY (caps1 == NULL || caps2 == NULL))
- return FALSE;
-
if (GST_CAPS_LEN (caps1) != GST_CAPS_LEN (caps2))
return FALSE;
* much better than a simple loop.
*
* This algorithm zigzags over the caps structures as demonstrated in
- * the folowing matrix:
+ * the following matrix:
*
* caps1 0 1 2 3
* +------------- total distance: +-------------
}
static GstCaps *
-gst_caps_intersect_zig_zag (const GstCaps * caps1, const GstCaps * caps2)
+gst_caps_intersect_zig_zag (GstCaps * caps1, GstCaps * caps2)
{
guint64 i; /* index can be up to 2 * G_MAX_UINT */
guint j, k, len1, len2;
/* caps are exactly the same pointers, just copy one caps */
if (G_UNLIKELY (caps1 == caps2))
- return _gst_caps_copy (caps1);
+ return gst_caps_ref (caps1);
/* empty caps on either side, return empty */
if (G_UNLIKELY (CAPS_IS_EMPTY (caps1) || CAPS_IS_EMPTY (caps2)))
- return gst_caps_new_empty ();
+ return gst_caps_ref (GST_CAPS_NONE);
/* one of the caps is any, just copy the other caps */
if (G_UNLIKELY (CAPS_IS_ANY (caps1)))
- return _gst_caps_copy (caps2);
+ return gst_caps_ref (caps2);
if (G_UNLIKELY (CAPS_IS_ANY (caps2)))
- return _gst_caps_copy (caps1);
+ return gst_caps_ref (caps1);
dest = gst_caps_new_empty ();
* much better than a simple loop.
*
* This algorithm zigzags over the caps structures as demonstrated in
- * the folowing matrix:
+ * the following matrix:
*
* caps1
* +-------------
istruct = gst_structure_intersect (struct1, struct2);
- gst_caps_merge_structure (dest, istruct);
+ dest = gst_caps_merge_structure (dest, istruct);
/* move down left */
k++;
if (G_UNLIKELY (j == 0))
* Returns: the new #GstCaps
*/
static GstCaps *
-gst_caps_intersect_first (const GstCaps * caps1, const GstCaps * caps2)
+gst_caps_intersect_first (GstCaps * caps1, GstCaps * caps2)
{
guint i;
guint j, len1, len2;
/* caps are exactly the same pointers, just copy one caps */
if (G_UNLIKELY (caps1 == caps2))
- return gst_caps_copy (caps1);
+ return gst_caps_ref (caps1);
/* empty caps on either side, return empty */
if (G_UNLIKELY (CAPS_IS_EMPTY (caps1) || CAPS_IS_EMPTY (caps2)))
- return gst_caps_new_empty ();
+ return gst_caps_ref (GST_CAPS_NONE);
/* one of the caps is any, just copy the other caps */
if (G_UNLIKELY (CAPS_IS_ANY (caps1)))
- return gst_caps_copy (caps2);
+ return gst_caps_ref (caps2);
if (G_UNLIKELY (CAPS_IS_ANY (caps2)))
- return gst_caps_copy (caps1);
+ return gst_caps_ref (caps1);
dest = gst_caps_new_empty ();
struct2 = gst_caps_get_structure_unchecked (caps2, j);
istruct = gst_structure_intersect (struct1, struct2);
if (istruct)
- gst_caps_merge_structure (dest, istruct);
+ dest = gst_caps_merge_structure (dest, istruct);
}
}
* Since: 0.10.33
*/
GstCaps *
-gst_caps_intersect_full (const GstCaps * caps1, const GstCaps * caps2,
+gst_caps_intersect_full (GstCaps * caps1, GstCaps * caps2,
GstCapsIntersectMode mode)
{
g_return_val_if_fail (GST_IS_CAPS (caps1), NULL);
* Returns: the new #GstCaps
*/
GstCaps *
-gst_caps_intersect (const GstCaps * caps1, const GstCaps * caps2)
+gst_caps_intersect (GstCaps * caps1, GstCaps * caps2)
{
return gst_caps_intersect_full (caps1, caps2, GST_CAPS_INTERSECT_ZIG_ZAG);
}
* Returns: the resulting caps
*/
GstCaps *
-gst_caps_subtract (const GstCaps * minuend, const GstCaps * subtrahend)
+gst_caps_subtract (GstCaps * minuend, GstCaps * subtrahend)
{
guint i, j, sublen;
GstStructure *min;
return gst_caps_new_empty ();
}
if (CAPS_IS_EMPTY_SIMPLE (subtrahend))
- return _gst_caps_copy (minuend);
+ return gst_caps_ref (minuend);
/* FIXME: Do we want this here or above?
The reason we need this is that there is no definition about what
}
gst_caps_unref (src);
- gst_caps_do_simplify (dest);
- return dest;
-}
-
-/* union operation */
-
-#if 0
-static GstStructure *
-gst_caps_structure_union (const GstStructure * struct1,
- const GstStructure * struct2)
-{
- int i;
- GstStructure *dest;
- const GstStructureField *field1;
- const GstStructureField *field2;
- int ret;
-
- /* FIXME this doesn't actually work */
-
- if (struct1->name != struct2->name)
- return NULL;
-
- dest = gst_structure_new_id_empty (struct1->name);
-
- for (i = 0; i < struct1->fields->len; i++) {
- GValue dest_value = { 0 };
-
- field1 = GST_STRUCTURE_FIELD (struct1, i);
- field2 = gst_structure_id_get_field (struct2, field1->name);
-
- if (field2 == NULL) {
- continue;
- } else {
- if (gst_value_union (&dest_value, &field1->value, &field2->value)) {
- gst_structure_set_value (dest, g_quark_to_string (field1->name),
- &dest_value);
- } else {
- ret = gst_value_compare (&field1->value, &field2->value);
- }
- }
- }
-
+ dest = gst_caps_simplify (dest);
return dest;
}
-#endif
-
-/**
- * gst_caps_union:
- * @caps1: a #GstCaps to union
- * @caps2: a #GstCaps to union
- *
- * Creates a new #GstCaps that contains all the formats that are in
- * either @caps1 and @caps2.
- *
- * Returns: the new #GstCaps
- */
-GstCaps *
-gst_caps_union (const GstCaps * caps1, const GstCaps * caps2)
-{
- GstCaps *dest1;
- GstCaps *dest2;
-
- /* NULL pointers are no correct GstCaps */
- g_return_val_if_fail (caps1 != NULL, NULL);
- g_return_val_if_fail (caps2 != NULL, NULL);
-
- if (CAPS_IS_EMPTY (caps1))
- return _gst_caps_copy (caps2);
-
- if (CAPS_IS_EMPTY (caps2))
- return _gst_caps_copy (caps1);
-
- if (CAPS_IS_ANY (caps1) || CAPS_IS_ANY (caps2))
- return gst_caps_new_any ();
-
- dest1 = _gst_caps_copy (caps1);
- dest2 = _gst_caps_copy (caps2);
- gst_caps_append (dest1, dest2);
-
- gst_caps_do_simplify (dest1);
- return dest1;
-}
/* normalize/simplify operations */
/**
* gst_caps_normalize:
- * @caps: a #GstCaps to normalize
+ * @caps: (transfer full): a #GstCaps to normalize
*
- * Creates a new #GstCaps that represents the same set of formats as
+ * Returns a #GstCaps that represents the same set of formats as
* @caps, but contains no lists. Each list is expanded into separate
* @GstStructures.
*
- * Returns: the new #GstCaps
+ * This function takes ownership of @caps.
+ *
+ * Returns: (transfer full): the normalized #GstCaps
*/
GstCaps *
-gst_caps_normalize (const GstCaps * caps)
+gst_caps_normalize (GstCaps * caps)
{
NormalizeForeach nf;
- GstCaps *newcaps;
guint i;
g_return_val_if_fail (GST_IS_CAPS (caps), NULL);
- newcaps = _gst_caps_copy (caps);
- nf.caps = newcaps;
+ caps = gst_caps_make_writable (caps);
- for (i = 0; i < gst_caps_get_size (newcaps); i++) {
- nf.structure = gst_caps_get_structure_unchecked (newcaps, i);
+ nf.caps = caps;
+
+ for (i = 0; i < gst_caps_get_size (nf.caps); i++) {
+ nf.structure = gst_caps_get_structure_unchecked (nf.caps, i);
while (!gst_structure_foreach (nf.structure,
gst_caps_normalize_foreach, &nf));
}
- return newcaps;
+ return nf.caps;
}
static gint
static gboolean
gst_caps_structure_simplify (GstStructure ** result,
- const GstStructure * simplify, GstStructure * compare)
+ GstStructure * simplify, GstStructure * compare)
{
GSList *list;
UnionField field = { 0, {0,}, NULL };
/* try to union both structs */
field.compare = compare;
- if (gst_structure_foreach ((GstStructure *) simplify,
+ if (gst_structure_foreach (simplify,
gst_caps_structure_figure_out_union, &field)) {
gboolean ret = FALSE;
}
/**
- * gst_caps_do_simplify:
- * @caps: a #GstCaps to simplify
+ * gst_caps_simplify:
+ * @caps: (transfer full): a #GstCaps to simplify
*
- * Modifies the given @caps inplace into a representation that represents the
+ * Converts the given @caps into a representation that represents the
* same set of formats, but in a simpler form. Component structures that are
* identical are merged. Component structures that have values that can be
* merged are also merged.
*
- * Returns: TRUE, if the caps could be simplified
+ * This method does not preserve the original order of @caps.
+ *
+ * Returns: The simplified caps.
*/
-gboolean
-gst_caps_do_simplify (GstCaps * caps)
+GstCaps *
+gst_caps_simplify (GstCaps * caps)
{
GstStructure *simplify, *compare, *result = NULL;
gint i, j, start;
- gboolean changed = FALSE;
- g_return_val_if_fail (caps != NULL, FALSE);
- g_return_val_if_fail (IS_WRITABLE (caps), FALSE);
+ g_return_val_if_fail (GST_IS_CAPS (caps), NULL);
- if (gst_caps_get_size (caps) < 2)
- return FALSE;
+ start = GST_CAPS_LEN (caps) - 1;
+ /* one caps, already as simple as can be */
+ if (start == 0)
+ return caps;
+
+ caps = gst_caps_make_writable (caps);
g_ptr_array_sort (GST_CAPS_ARRAY (caps), gst_caps_compare_structures);
- start = GST_CAPS_LEN (caps) - 1;
- for (i = GST_CAPS_LEN (caps) - 1; i >= 0; i--) {
+ for (i = start; i >= 0; i--) {
simplify = gst_caps_get_structure_unchecked (caps, i);
+ compare = gst_caps_get_structure_unchecked (caps, start);
if (gst_structure_get_name_id (simplify) !=
- gst_structure_get_name_id (gst_caps_get_structure_unchecked (caps,
- start)))
+ gst_structure_get_name_id (compare))
start = i;
for (j = start; j >= 0; j--) {
if (j == i)
start--;
break;
}
- changed = TRUE;
}
}
}
-
- if (!changed)
- return FALSE;
-
- /* gst_caps_do_simplify (caps); */
- return TRUE;
+ return caps;
}
/**
* gst_caps_fixate:
- * @caps: a #GstCaps to fixate
+ * @caps: (transfer full): a #GstCaps to fixate
*
- * Modifies the given @caps inplace into a representation with only fixed
+ * Modifies the given @caps into a representation with only fixed
* values. First the caps will be truncated and then the first structure will be
- * fixated with gst_structure_fixate(). @caps should be writable.
+ * fixated with gst_structure_fixate().
+ *
+ * Returns: (transfer full): the fixated caps
*/
-void
+GstCaps *
gst_caps_fixate (GstCaps * caps)
{
GstStructure *s;
- g_return_if_fail (GST_IS_CAPS (caps));
- g_return_if_fail (IS_WRITABLE (caps));
+ g_return_val_if_fail (GST_IS_CAPS (caps), NULL);
/* default fixation */
- gst_caps_truncate (caps);
+ caps = gst_caps_truncate (caps);
+ caps = gst_caps_make_writable (caps);
s = gst_caps_get_structure (caps, 0);
gst_structure_fixate (s);
+
+ return caps;
}
/* utility */
* |[
* GST_LOG ("caps are %" GST_PTR_FORMAT, caps);
* ]|
- * This prints the caps in human readble form.
+ * This prints the caps in human readable form.
*
* Returns: (transfer full): a newly allocated string representing @caps.
*/
projects / platform / upstream / gstreamer.git / blobdiff