2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wtay@chello.be>
5 * gstbuffer.c: Buffer operations
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
20 * Boston, MA 02110-1301, USA.
26 * @short_description: Data-passing buffer type
27 * @see_also: #GstPad, #GstMiniObject, #GstMemory, #GstMeta, #GstBufferPool
29 * Buffers are the basic unit of data transfer in GStreamer. They contain the
30 * timing and offset along with other arbitrary metadata that is associated
31 * with the #GstMemory blocks that the buffer contains.
33 * Buffers are usually created with gst_buffer_new(). After a buffer has been
34 * created one will typically allocate memory for it and add it to the buffer.
35 * The following example creates a buffer that can hold a given video frame
36 * with a given width, height and bits per plane.
37 * |[<!-- language="C" -->
40 * gint size, width, height, bpp;
42 * size = width * height * bpp;
43 * buffer = gst_buffer_new ();
44 * memory = gst_allocator_alloc (NULL, size, NULL);
45 * gst_buffer_insert_memory (buffer, -1, memory);
49 * Alternatively, use gst_buffer_new_allocate() to create a buffer with
50 * preallocated data of a given size.
52 * Buffers can contain a list of #GstMemory objects. You can retrieve how many
53 * memory objects with gst_buffer_n_memory() and you can get a pointer
54 * to memory with gst_buffer_peek_memory()
56 * A buffer will usually have timestamps, and a duration, but neither of these
57 * are guaranteed (they may be set to #GST_CLOCK_TIME_NONE). Whenever a
58 * meaningful value can be given for these, they should be set. The timestamps
59 * and duration are measured in nanoseconds (they are #GstClockTime values).
61 * The buffer DTS refers to the timestamp when the buffer should be decoded and
62 * is usually monotonically increasing. The buffer PTS refers to the timestamp when
63 * the buffer content should be presented to the user and is not always
64 * monotonically increasing.
66 * A buffer can also have one or both of a start and an end offset. These are
67 * media-type specific. For video buffers, the start offset will generally be
68 * the frame number. For audio buffers, it will be the number of samples
69 * produced so far. For compressed data, it could be the byte offset in a
70 * source or destination file. Likewise, the end offset will be the offset of
71 * the end of the buffer. These can only be meaningfully interpreted if you
72 * know the media type of the buffer (the preceding CAPS event). Either or both
73 * can be set to #GST_BUFFER_OFFSET_NONE.
75 * gst_buffer_ref() is used to increase the refcount of a buffer. This must be
76 * done when you want to keep a handle to the buffer after pushing it to the
77 * next element. The buffer refcount determines the writability of the buffer, a
78 * buffer is only writable when the refcount is exactly 1, i.e. when the caller
79 * has the only reference to the buffer.
81 * To efficiently create a smaller buffer out of an existing one, you can
82 * use gst_buffer_copy_region(). This method tries to share the memory objects
83 * between the two buffers.
85 * If a plug-in wants to modify the buffer data or metadata in-place, it should
86 * first obtain a buffer that is safe to modify by using
87 * gst_buffer_make_writable(). This function is optimized so that a copy will
88 * only be made when it is necessary.
90 * Several flags of the buffer can be set and unset with the
91 * GST_BUFFER_FLAG_SET() and GST_BUFFER_FLAG_UNSET() macros. Use
92 * GST_BUFFER_FLAG_IS_SET() to test if a certain #GstBufferFlags flag is set.
94 * Buffers can be efficiently merged into a larger buffer with
95 * gst_buffer_append(). Copying of memory will only be done when absolutely
98 * Arbitrary extra metadata can be set on a buffer with gst_buffer_add_meta().
99 * Metadata can be retrieved with gst_buffer_get_meta(). See also #GstMeta
101 * An element should either unref the buffer or push it out on a src pad
102 * using gst_pad_push() (see #GstPad).
104 * Buffers are usually freed by unreffing them with gst_buffer_unref(). When
105 * the refcount drops to 0, any memory and metadata pointed to by the buffer is
106 * unreffed as well. Buffers allocated from a #GstBufferPool will be returned to
107 * the pool when the refcount drops to 0.
109 * The #GstParentBufferMeta is a meta which can be attached to a #GstBuffer
110 * to hold a reference to another buffer that is only released when the child
111 * #GstBuffer is released.
113 * Typically, #GstParentBufferMeta is used when the child buffer is directly
114 * using the #GstMemory of the parent buffer, and wants to prevent the parent
115 * buffer from being returned to a buffer pool until the #GstMemory is available
116 * for re-use. (Since: 1.6)
119 #include "gst_private.h"
128 #include "gstbuffer.h"
129 #include "gstbufferpool.h"
131 #include "gstutils.h"
132 #include "gstversion.h"
134 GType _gst_buffer_type = 0;
136 /* info->size will be sizeof(FooMeta) which contains a GstMeta at the beginning
137 * too, and then there is again a GstMeta in GstMetaItem, so subtract one. */
138 #define ITEM_SIZE(info) ((info)->size + sizeof (GstMetaItem) - sizeof (GstMeta))
140 #define GST_BUFFER_MEM_MAX 16
142 #define GST_BUFFER_SLICE_SIZE(b) (((GstBufferImpl *)(b))->slice_size)
143 #define GST_BUFFER_MEM_LEN(b) (((GstBufferImpl *)(b))->len)
144 #define GST_BUFFER_MEM_ARRAY(b) (((GstBufferImpl *)(b))->mem)
145 #define GST_BUFFER_MEM_PTR(b,i) (((GstBufferImpl *)(b))->mem[i])
146 #define GST_BUFFER_BUFMEM(b) (((GstBufferImpl *)(b))->bufmem)
147 #define GST_BUFFER_META(b) (((GstBufferImpl *)(b))->item)
148 #define GST_BUFFER_TAIL_META(b) (((GstBufferImpl *)(b))->tail_item)
156 /* the memory blocks */
158 GstMemory *mem[GST_BUFFER_MEM_MAX];
160 /* memory of the buffer when allocated from 1 chunk */
163 /* FIXME, make metadata allocation more efficient by using part of the
166 GstMetaItem *tail_item;
169 static gint64 meta_seq; /* 0 *//* ATOMIC */
171 /* TODO: use GLib's once https://gitlab.gnome.org/GNOME/glib/issues/1076 lands */
172 #if defined(__GCC_HAVE_SYNC_COMPARE_AND_SWAP_8)
174 gst_atomic_int64_inc (volatile gint64 * atomic)
176 return __sync_fetch_and_add (atomic, 1);
178 #elif defined (G_PLATFORM_WIN32)
181 gst_atomic_int64_inc (volatile gint64 * atomic)
183 return InterlockedExchangeAdd64 (atomic, 1);
186 #warning No 64-bit atomic int defined for this platform/toolchain!
187 #define NO_64BIT_ATOMIC_INT_FOR_PLATFORM
188 G_LOCK_DEFINE_STATIC (meta_seq);
190 gst_atomic_int64_inc (volatile gint64 * atomic)
203 _is_span (GstMemory ** mem, gsize len, gsize * poffset, GstMemory ** parent)
205 GstMemory *mcur, *mprv;
206 gboolean have_offset = FALSE;
211 for (i = 0; i < len; i++) {
219 /* check if memory is contiguous */
220 if (!gst_memory_is_span (mprv, mcur, &poffs))
227 *parent = mprv->parent;
237 _actual_merged_memory (GstBuffer * buffer, guint idx, guint length)
239 GstMemory **mem, *result = NULL;
240 GstMemory *parent = NULL;
241 gsize size, poffset = 0;
243 mem = GST_BUFFER_MEM_ARRAY (buffer);
245 size = gst_buffer_get_sizes_range (buffer, idx, length, NULL, NULL);
247 if (G_UNLIKELY (_is_span (mem + idx, length, &poffset, &parent))) {
248 if (!GST_MEMORY_IS_NO_SHARE (parent))
249 result = gst_memory_share (parent, poffset, size);
251 GST_CAT_DEBUG (GST_CAT_PERFORMANCE, "copy for merge %p", parent);
252 result = gst_memory_copy (parent, poffset, size);
255 gsize i, tocopy, left;
256 GstMapInfo sinfo, dinfo;
259 result = gst_allocator_alloc (NULL, size, NULL);
260 if (result == NULL || !gst_memory_map (result, &dinfo, GST_MAP_WRITE)) {
261 GST_CAT_ERROR (GST_CAT_BUFFER, "Failed to map memory writable");
263 gst_memory_unref (result);
270 for (i = idx; i < (idx + length) && left > 0; i++) {
271 if (!gst_memory_map (mem[i], &sinfo, GST_MAP_READ)) {
272 GST_CAT_ERROR (GST_CAT_BUFFER,
273 "buffer %p, idx %u, length %u failed to map readable", buffer,
275 gst_memory_unmap (result, &dinfo);
276 gst_memory_unref (result);
279 tocopy = MIN (sinfo.size, left);
280 GST_CAT_DEBUG (GST_CAT_PERFORMANCE,
281 "memcpy %" G_GSIZE_FORMAT " bytes for merge %p from memory %p",
282 tocopy, result, mem[i]);
283 memcpy (ptr, (guint8 *) sinfo.data, tocopy);
286 gst_memory_unmap (mem[i], &sinfo);
288 gst_memory_unmap (result, &dinfo);
294 static inline GstMemory *
295 _get_merged_memory (GstBuffer * buffer, guint idx, guint length)
297 GST_CAT_LOG (GST_CAT_BUFFER, "buffer %p, idx %u, length %u", buffer, idx,
300 if (G_UNLIKELY (length == 0))
303 if (G_LIKELY (length == 1))
304 return gst_memory_ref (GST_BUFFER_MEM_PTR (buffer, idx));
306 return _actual_merged_memory (buffer, idx, length);
311 _replace_memory (GstBuffer * buffer, guint len, guint idx, guint length,
318 GST_CAT_LOG (GST_CAT_BUFFER,
319 "buffer %p replace %u-%" G_GSIZE_FORMAT " with memory %p", buffer, idx,
322 /* unref old memory */
323 for (i = idx; i < end; i++) {
324 GstMemory *old = GST_BUFFER_MEM_PTR (buffer, i);
326 gst_memory_unlock (old, GST_LOCK_FLAG_EXCLUSIVE);
327 gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (old),
328 GST_MINI_OBJECT_CAST (buffer));
329 gst_memory_unref (old);
333 /* replace with single memory */
334 gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (mem),
335 GST_MINI_OBJECT_CAST (buffer));
336 gst_memory_lock (mem, GST_LOCK_FLAG_EXCLUSIVE);
337 GST_BUFFER_MEM_PTR (buffer, idx) = mem;
343 memmove (&GST_BUFFER_MEM_PTR (buffer, idx),
344 &GST_BUFFER_MEM_PTR (buffer, end), (len - end) * sizeof (gpointer));
346 GST_BUFFER_MEM_LEN (buffer) = len - length;
347 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
351 * gst_buffer_get_flags:
352 * @buffer: a #GstBuffer
354 * Get the #GstBufferFlags flags set on this buffer.
356 * Returns: the flags set on this buffer.
361 gst_buffer_get_flags (GstBuffer * buffer)
363 return (GstBufferFlags) GST_BUFFER_FLAGS (buffer);
367 * gst_buffer_flag_is_set:
368 * @buffer: a #GstBuffer
369 * @flags: the #GstBufferFlags flag to check.
371 * Gives the status of a specific flag on a buffer.
373 * Returns: %TRUE if all flags in @flags are found on @buffer.
378 gst_buffer_has_flags (GstBuffer * buffer, GstBufferFlags flags)
380 return GST_BUFFER_FLAG_IS_SET (buffer, flags);
384 * gst_buffer_set_flags:
385 * @buffer: a #GstBuffer
386 * @flags: the #GstBufferFlags to set.
388 * Sets one or more buffer flags on a buffer.
390 * Returns: %TRUE if @flags were successfully set on buffer.
395 gst_buffer_set_flags (GstBuffer * buffer, GstBufferFlags flags)
397 GST_BUFFER_FLAG_SET (buffer, flags);
402 * gst_buffer_unset_flags:
403 * @buffer: a #GstBuffer
404 * @flags: the #GstBufferFlags to clear
406 * Clears one or more buffer flags.
408 * Returns: true if @flags is successfully cleared from buffer.
413 gst_buffer_unset_flags (GstBuffer * buffer, GstBufferFlags flags)
415 GST_BUFFER_FLAG_UNSET (buffer, flags);
421 /* transfer full for return and transfer none for @mem */
422 static inline GstMemory *
423 _memory_get_exclusive_reference (GstMemory * mem)
425 GstMemory *ret = NULL;
427 if (gst_memory_lock (mem, GST_LOCK_FLAG_EXCLUSIVE)) {
428 ret = gst_memory_ref (mem);
430 /* we cannot take another exclusive lock as the memory is already
431 * locked WRITE + EXCLUSIVE according to part-miniobject.txt */
432 ret = gst_memory_copy (mem, 0, -1);
435 if (!gst_memory_lock (ret, GST_LOCK_FLAG_EXCLUSIVE)) {
436 gst_memory_unref (ret);
443 GST_CAT_WARNING (GST_CAT_BUFFER, "Failed to acquire an exclusive lock for "
450 _memory_add (GstBuffer * buffer, gint idx, GstMemory * mem)
452 guint i, len = GST_BUFFER_MEM_LEN (buffer);
454 GST_CAT_LOG (GST_CAT_BUFFER, "buffer %p, idx %d, mem %p", buffer, idx, mem);
456 if (G_UNLIKELY (len >= GST_BUFFER_MEM_MAX)) {
457 /* too many buffer, span them. */
458 /* FIXME, there is room for improvement here: We could only try to merge
459 * 2 buffers to make some room. If we can't efficiently merge 2 buffers we
460 * could try to only merge the two smallest buffers to avoid memcpy, etc. */
461 GST_CAT_DEBUG (GST_CAT_PERFORMANCE, "memory array overflow in buffer %p",
463 _replace_memory (buffer, len, 0, len, _get_merged_memory (buffer, 0, len));
464 /* we now have 1 single spanned buffer */
471 for (i = len; i > idx; i--) {
472 /* move buffers to insert, FIXME, we need to insert first and then merge */
473 GST_BUFFER_MEM_PTR (buffer, i) = GST_BUFFER_MEM_PTR (buffer, i - 1);
475 /* and insert the new buffer */
476 GST_BUFFER_MEM_PTR (buffer, idx) = mem;
477 GST_BUFFER_MEM_LEN (buffer) = len + 1;
478 gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (mem),
479 GST_MINI_OBJECT_CAST (buffer));
481 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
484 GST_DEFINE_MINI_OBJECT_TYPE (GstBuffer, gst_buffer);
487 _priv_gst_buffer_initialize (void)
489 _gst_buffer_type = gst_buffer_get_type ();
491 #ifdef NO_64BIT_ATOMIC_INT_FOR_PLATFORM
492 GST_CAT_WARNING (GST_CAT_PERFORMANCE,
493 "No 64-bit atomic int defined for this platform/toolchain!");
498 * gst_buffer_get_max_memory:
500 * Get the maximum amount of memory blocks that a buffer can hold. This is a
501 * compile time constant that can be queried with the function.
503 * When more memory blocks are added, existing memory blocks will be merged
504 * together to make room for the new block.
506 * Returns: the maximum amount of memory blocks that a buffer can hold.
511 gst_buffer_get_max_memory (void)
513 return GST_BUFFER_MEM_MAX;
517 * gst_buffer_copy_into:
518 * @dest: a destination #GstBuffer
519 * @src: a source #GstBuffer
520 * @flags: flags indicating what metadata fields should be copied.
521 * @offset: offset to copy from
522 * @size: total size to copy. If -1, all data is copied.
524 * Copies the information from @src into @dest.
526 * If @dest already contains memory and @flags contains GST_BUFFER_COPY_MEMORY,
527 * the memory from @src will be appended to @dest.
529 * @flags indicate which fields will be copied.
531 * Returns: %TRUE if the copying succeeded, %FALSE otherwise.
534 gst_buffer_copy_into (GstBuffer * dest, GstBuffer * src,
535 GstBufferCopyFlags flags, gsize offset, gsize size)
539 gboolean region = FALSE;
541 g_return_val_if_fail (dest != NULL, FALSE);
542 g_return_val_if_fail (src != NULL, FALSE);
544 /* nothing to copy if the buffers are the same */
545 if (G_UNLIKELY (dest == src))
548 g_return_val_if_fail (gst_buffer_is_writable (dest), FALSE);
550 bufsize = gst_buffer_get_size (src);
551 g_return_val_if_fail (bufsize >= offset, FALSE);
555 size = bufsize - offset;
558 g_return_val_if_fail (bufsize >= offset + size, FALSE);
560 GST_CAT_LOG (GST_CAT_BUFFER, "copy %p to %p, offset %" G_GSIZE_FORMAT
561 "-%" G_GSIZE_FORMAT "/%" G_GSIZE_FORMAT, src, dest, offset, size,
564 if (flags & GST_BUFFER_COPY_FLAGS) {
566 guint flags_mask = ~GST_BUFFER_FLAG_TAG_MEMORY;
568 GST_MINI_OBJECT_FLAGS (dest) =
569 (GST_MINI_OBJECT_FLAGS (src) & flags_mask) |
570 (GST_MINI_OBJECT_FLAGS (dest) & ~flags_mask);
573 if (flags & GST_BUFFER_COPY_TIMESTAMPS) {
575 GST_BUFFER_PTS (dest) = GST_BUFFER_PTS (src);
576 GST_BUFFER_DTS (dest) = GST_BUFFER_DTS (src);
577 GST_BUFFER_OFFSET (dest) = GST_BUFFER_OFFSET (src);
578 if (size == bufsize) {
579 GST_BUFFER_DURATION (dest) = GST_BUFFER_DURATION (src);
580 GST_BUFFER_OFFSET_END (dest) = GST_BUFFER_OFFSET_END (src);
583 GST_BUFFER_PTS (dest) = GST_CLOCK_TIME_NONE;
584 GST_BUFFER_DTS (dest) = GST_CLOCK_TIME_NONE;
585 GST_BUFFER_DURATION (dest) = GST_CLOCK_TIME_NONE;
586 GST_BUFFER_OFFSET (dest) = GST_BUFFER_OFFSET_NONE;
587 GST_BUFFER_OFFSET_END (dest) = GST_BUFFER_OFFSET_NONE;
591 if (flags & GST_BUFFER_COPY_MEMORY) {
592 gsize skip, left, len, dest_len, i, bsize;
595 deep = flags & GST_BUFFER_COPY_DEEP;
597 len = GST_BUFFER_MEM_LEN (src);
598 dest_len = GST_BUFFER_MEM_LEN (dest);
602 /* copy and make regions of the memory */
603 for (i = 0; i < len && left > 0; i++) {
604 GstMemory *mem = GST_BUFFER_MEM_PTR (src, i);
609 /* don't copy buffer */
612 GstMemory *newmem = NULL;
615 tocopy = MIN (bsize - skip, left);
617 if (tocopy < bsize && !deep && !GST_MEMORY_IS_NO_SHARE (mem)) {
618 /* we need to clip something */
619 newmem = gst_memory_share (mem, skip, tocopy);
621 gst_memory_lock (newmem, GST_LOCK_FLAG_EXCLUSIVE);
626 if (deep || GST_MEMORY_IS_NO_SHARE (mem) || (!newmem && tocopy < bsize)) {
627 /* deep copy or we're not allowed to share this memory
628 * between buffers, always copy then */
629 newmem = gst_memory_copy (mem, skip, tocopy);
631 gst_memory_lock (newmem, GST_LOCK_FLAG_EXCLUSIVE);
634 } else if (!newmem) {
635 newmem = _memory_get_exclusive_reference (mem);
639 gst_buffer_remove_memory_range (dest, dest_len, -1);
643 _memory_add (dest, -1, newmem);
647 if (flags & GST_BUFFER_COPY_MERGE) {
650 len = GST_BUFFER_MEM_LEN (dest);
651 mem = _get_merged_memory (dest, 0, len);
653 gst_buffer_remove_memory_range (dest, dest_len, -1);
656 _replace_memory (dest, len, 0, len, mem);
660 if (flags & GST_BUFFER_COPY_META) {
661 /* NOTE: GstGLSyncMeta copying relies on the meta
662 * being copied now, after the buffer data,
663 * so this has to happen last */
664 for (walk = GST_BUFFER_META (src); walk; walk = walk->next) {
665 GstMeta *meta = &walk->meta;
666 const GstMetaInfo *info = meta->info;
668 /* Don't copy memory metas if we only copied part of the buffer, didn't
669 * copy memories or merged memories. In all these cases the memory
670 * structure has changed and the memory meta becomes meaningless.
672 if ((region || !(flags & GST_BUFFER_COPY_MEMORY)
673 || (flags & GST_BUFFER_COPY_MERGE))
674 && gst_meta_api_type_has_tag (info->api, _gst_meta_tag_memory)) {
675 GST_CAT_DEBUG (GST_CAT_BUFFER,
676 "don't copy memory meta %p of API type %s", meta,
677 g_type_name (info->api));
678 } else if (info->transform_func) {
679 GstMetaTransformCopy copy_data;
681 copy_data.region = region;
682 copy_data.offset = offset;
683 copy_data.size = size;
685 if (!info->transform_func (dest, meta, src,
686 _gst_meta_transform_copy, ©_data)) {
687 GST_CAT_ERROR (GST_CAT_BUFFER,
688 "failed to copy meta %p of API type %s", meta,
689 g_type_name (info->api));
699 gst_buffer_copy_with_flags (const GstBuffer * buffer, GstBufferCopyFlags flags)
703 g_return_val_if_fail (buffer != NULL, NULL);
705 /* create a fresh new buffer */
706 copy = gst_buffer_new ();
708 /* copy what the 'flags' want from our parent */
709 /* FIXME why we can't pass const to gst_buffer_copy_into() ? */
710 if (!gst_buffer_copy_into (copy, (GstBuffer *) buffer, flags, 0, -1))
711 gst_buffer_replace (©, NULL);
714 GST_BUFFER_FLAG_UNSET (copy, GST_BUFFER_FLAG_TAG_MEMORY);
720 _gst_buffer_copy (const GstBuffer * buffer)
722 return gst_buffer_copy_with_flags (buffer, GST_BUFFER_COPY_ALL);
726 * gst_buffer_copy_deep:
727 * @buf: a #GstBuffer.
729 * Create a copy of the given buffer. This will make a newly allocated
730 * copy of the data the source buffer contains.
732 * Returns: (transfer full): a new copy of @buf.
737 gst_buffer_copy_deep (const GstBuffer * buffer)
739 return gst_buffer_copy_with_flags (buffer,
740 GST_BUFFER_COPY_ALL | GST_BUFFER_COPY_DEEP);
743 /* the default dispose function revives the buffer and returns it to the
744 * pool when there is a pool */
746 _gst_buffer_dispose (GstBuffer * buffer)
750 /* no pool, do free */
751 if ((pool = buffer->pool) == NULL)
754 /* keep the buffer alive */
755 gst_buffer_ref (buffer);
756 /* return the buffer to the pool */
757 GST_CAT_LOG (GST_CAT_BUFFER, "release %p to pool %p", buffer, pool);
758 gst_buffer_pool_release_buffer (pool, buffer);
764 _gst_buffer_free (GstBuffer * buffer)
766 GstMetaItem *walk, *next;
770 g_return_if_fail (buffer != NULL);
772 GST_CAT_LOG (GST_CAT_BUFFER, "finalize %p", buffer);
775 for (walk = GST_BUFFER_META (buffer); walk; walk = next) {
776 GstMeta *meta = &walk->meta;
777 const GstMetaInfo *info = meta->info;
779 /* call free_func if any */
781 info->free_func (meta, buffer);
784 /* and free the slice */
785 g_slice_free1 (ITEM_SIZE (info), walk);
788 /* get the size, when unreffing the memory, we could also unref the buffer
790 msize = GST_BUFFER_SLICE_SIZE (buffer);
792 /* free our memory */
793 len = GST_BUFFER_MEM_LEN (buffer);
794 for (i = 0; i < len; i++) {
795 gst_memory_unlock (GST_BUFFER_MEM_PTR (buffer, i), GST_LOCK_FLAG_EXCLUSIVE);
796 gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (GST_BUFFER_MEM_PTR
797 (buffer, i)), GST_MINI_OBJECT_CAST (buffer));
798 gst_memory_unref (GST_BUFFER_MEM_PTR (buffer, i));
801 /* we set msize to 0 when the buffer is part of the memory block */
804 memset (buffer, 0xff, msize);
806 g_slice_free1 (msize, buffer);
808 gst_memory_unref (GST_BUFFER_BUFMEM (buffer));
813 gst_buffer_init (GstBufferImpl * buffer, gsize size)
815 gst_mini_object_init (GST_MINI_OBJECT_CAST (buffer), 0, _gst_buffer_type,
816 (GstMiniObjectCopyFunction) _gst_buffer_copy,
817 (GstMiniObjectDisposeFunction) _gst_buffer_dispose,
818 (GstMiniObjectFreeFunction) _gst_buffer_free);
820 GST_BUFFER_SLICE_SIZE (buffer) = size;
822 GST_BUFFER (buffer)->pool = NULL;
823 GST_BUFFER_PTS (buffer) = GST_CLOCK_TIME_NONE;
824 GST_BUFFER_DTS (buffer) = GST_CLOCK_TIME_NONE;
825 GST_BUFFER_DURATION (buffer) = GST_CLOCK_TIME_NONE;
826 GST_BUFFER_OFFSET (buffer) = GST_BUFFER_OFFSET_NONE;
827 GST_BUFFER_OFFSET_END (buffer) = GST_BUFFER_OFFSET_NONE;
829 GST_BUFFER_MEM_LEN (buffer) = 0;
830 GST_BUFFER_META (buffer) = NULL;
836 * Creates a newly allocated buffer without any data.
840 * Returns: (transfer full): the new #GstBuffer.
843 gst_buffer_new (void)
845 GstBufferImpl *newbuf;
847 newbuf = g_slice_new (GstBufferImpl);
848 GST_CAT_LOG (GST_CAT_BUFFER, "new %p", newbuf);
850 gst_buffer_init (newbuf, sizeof (GstBufferImpl));
852 return GST_BUFFER_CAST (newbuf);
856 * gst_buffer_new_allocate:
857 * @allocator: (transfer none) (allow-none): the #GstAllocator to use, or %NULL to use the
859 * @size: the size in bytes of the new buffer's data.
860 * @params: (transfer none) (allow-none): optional parameters
862 * Tries to create a newly allocated buffer with data of the given size and
863 * extra parameters from @allocator. If the requested amount of memory can't be
864 * allocated, %NULL will be returned. The allocated buffer memory is not cleared.
866 * When @allocator is %NULL, the default memory allocator will be used.
868 * Note that when @size == 0, the buffer will not have memory associated with it.
872 * Returns: (transfer full) (nullable): a new #GstBuffer, or %NULL if
873 * the memory couldn't be allocated.
876 gst_buffer_new_allocate (GstAllocator * allocator, gsize size,
877 GstAllocationParams * params)
888 mem = gst_allocator_alloc (allocator, size, params);
889 if (G_UNLIKELY (mem == NULL))
895 newbuf = gst_buffer_new ();
898 gst_memory_lock (mem, GST_LOCK_FLAG_EXCLUSIVE);
899 _memory_add (newbuf, -1, mem);
902 GST_CAT_LOG (GST_CAT_BUFFER,
903 "new buffer %p of size %" G_GSIZE_FORMAT " from allocator %p", newbuf,
908 asize = sizeof (GstBufferImpl) + size;
909 data = g_slice_alloc (asize);
910 if (G_UNLIKELY (data == NULL))
913 newbuf = GST_BUFFER_CAST (data);
915 gst_buffer_init ((GstBufferImpl *) data, asize);
917 mem = gst_memory_new_wrapped (0, data + sizeof (GstBufferImpl), NULL,
919 _memory_add (newbuf, -1, mem, TRUE);
924 /* allocate memory and buffer, it might be interesting to do this but there
925 * are many complications. We need to keep the memory mapped to access the
926 * buffer fields and the memory for the buffer might be just very slow. We
927 * also need to do some more magic to get the alignment right. */
928 asize = sizeof (GstBufferImpl) + size;
929 mem = gst_allocator_alloc (allocator, asize, align);
930 if (G_UNLIKELY (mem == NULL))
933 /* map the data part and init the buffer in it, set the buffer size to 0 so
934 * that a finalize won't free the buffer */
935 data = gst_memory_map (mem, &asize, NULL, GST_MAP_WRITE);
936 gst_buffer_init ((GstBufferImpl *) data, 0);
937 gst_memory_unmap (mem);
939 /* strip off the buffer */
940 gst_memory_resize (mem, sizeof (GstBufferImpl), size);
942 newbuf = GST_BUFFER_CAST (data);
943 GST_BUFFER_BUFMEM (newbuf) = mem;
946 _memory_add (newbuf, -1, gst_memory_ref (mem), TRUE);
948 GST_BUFFER_FLAG_UNSET (newbuf, GST_BUFFER_FLAG_TAG_MEMORY);
955 GST_CAT_WARNING (GST_CAT_BUFFER,
956 "failed to allocate %" G_GSIZE_FORMAT " bytes", size);
962 * gst_buffer_new_wrapped_full:
963 * @flags: #GstMemoryFlags
964 * @data: (array length=size) (element-type guint8) (transfer none): data to wrap
965 * @maxsize: allocated size of @data
966 * @offset: offset in @data
967 * @size: size of valid data
968 * @user_data: (allow-none): user_data
969 * @notify: (allow-none) (scope async) (closure user_data): called with @user_data when the memory is freed
971 * Allocate a new buffer that wraps the given memory. @data must point to
972 * @maxsize of memory, the wrapped buffer will have the region from @offset and
975 * When the buffer is destroyed, @notify will be called with @user_data.
977 * The prefix/padding must be filled with 0 if @flags contains
978 * #GST_MEMORY_FLAG_ZERO_PREFIXED and #GST_MEMORY_FLAG_ZERO_PADDED respectively.
980 * Returns: (transfer full): a new #GstBuffer
983 gst_buffer_new_wrapped_full (GstMemoryFlags flags, gpointer data,
984 gsize maxsize, gsize offset, gsize size, gpointer user_data,
985 GDestroyNotify notify)
990 newbuf = gst_buffer_new ();
992 gst_memory_new_wrapped (flags, data, maxsize, offset, size, user_data,
994 gst_memory_lock (mem, GST_LOCK_FLAG_EXCLUSIVE);
995 _memory_add (newbuf, -1, mem);
996 GST_BUFFER_FLAG_UNSET (newbuf, GST_BUFFER_FLAG_TAG_MEMORY);
1002 * gst_buffer_new_wrapped:
1003 * @data: (array length=size) (element-type guint8) (transfer full): data to wrap
1004 * @size: allocated size of @data
1006 * Creates a new buffer that wraps the given @data. The memory will be freed
1007 * with g_free and will be marked writable.
1011 * Returns: (transfer full): a new #GstBuffer
1014 gst_buffer_new_wrapped (gpointer data, gsize size)
1016 return gst_buffer_new_wrapped_full (0, data, size, 0, size, data, g_free);
1020 * gst_buffer_new_wrapped_bytes:
1021 * @bytes: (transfer none): a #GBytes to wrap
1023 * Creates a new #GstBuffer that wraps the given @bytes. The data inside
1024 * @bytes cannot be %NULL and the resulting buffer will be marked as read only.
1028 * Returns: (transfer full): a new #GstBuffer wrapping @bytes
1033 gst_buffer_new_wrapped_bytes (GBytes * bytes)
1038 g_return_val_if_fail (bytes != NULL, NULL);
1039 bytes_data = (guint8 *) g_bytes_get_data (bytes, &size);
1040 g_return_val_if_fail (bytes_data != NULL, NULL);
1042 return gst_buffer_new_wrapped_full (GST_MEMORY_FLAG_READONLY, bytes_data,
1043 size, 0, size, g_bytes_ref (bytes), (GDestroyNotify) g_bytes_unref);
1047 * gst_buffer_n_memory:
1048 * @buffer: a #GstBuffer.
1050 * Get the amount of memory blocks that this buffer has. This amount is never
1051 * larger than what gst_buffer_get_max_memory() returns.
1053 * Returns: the number of memory blocks this buffer is made of.
1056 gst_buffer_n_memory (GstBuffer * buffer)
1058 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1060 return GST_BUFFER_MEM_LEN (buffer);
1064 * gst_buffer_prepend_memory:
1065 * @buffer: a #GstBuffer.
1066 * @mem: (transfer full): a #GstMemory.
1068 * Prepend the memory block @mem to @buffer. This function takes
1069 * ownership of @mem and thus doesn't increase its refcount.
1071 * This function is identical to gst_buffer_insert_memory() with an index of 0.
1072 * See gst_buffer_insert_memory() for more details.
1075 gst_buffer_prepend_memory (GstBuffer * buffer, GstMemory * mem)
1077 gst_buffer_insert_memory (buffer, 0, mem);
1081 * gst_buffer_append_memory:
1082 * @buffer: a #GstBuffer.
1083 * @mem: (transfer full): a #GstMemory.
1085 * Append the memory block @mem to @buffer. This function takes
1086 * ownership of @mem and thus doesn't increase its refcount.
1088 * This function is identical to gst_buffer_insert_memory() with an index of -1.
1089 * See gst_buffer_insert_memory() for more details.
1092 gst_buffer_append_memory (GstBuffer * buffer, GstMemory * mem)
1094 gst_buffer_insert_memory (buffer, -1, mem);
1098 * gst_buffer_insert_memory:
1099 * @buffer: a #GstBuffer.
1100 * @idx: the index to add the memory at, or -1 to append it to the end
1101 * @mem: (transfer full): a #GstMemory.
1103 * Insert the memory block @mem to @buffer at @idx. This function takes ownership
1104 * of @mem and thus doesn't increase its refcount.
1106 * Only gst_buffer_get_max_memory() can be added to a buffer. If more memory is
1107 * added, existing memory blocks will automatically be merged to make room for
1111 gst_buffer_insert_memory (GstBuffer * buffer, gint idx, GstMemory * mem)
1115 g_return_if_fail (GST_IS_BUFFER (buffer));
1116 g_return_if_fail (gst_buffer_is_writable (buffer));
1117 g_return_if_fail (mem != NULL);
1118 g_return_if_fail (idx == -1 ||
1119 (idx >= 0 && idx <= GST_BUFFER_MEM_LEN (buffer)));
1121 tmp = _memory_get_exclusive_reference (mem);
1122 g_return_if_fail (tmp != NULL);
1123 gst_memory_unref (mem);
1124 _memory_add (buffer, idx, tmp);
1128 _get_mapped (GstBuffer * buffer, guint idx, GstMapInfo * info,
1131 GstMemory *mem, *mapped;
1133 mem = gst_memory_ref (GST_BUFFER_MEM_PTR (buffer, idx));
1135 mapped = gst_memory_make_mapped (mem, info, flags);
1137 if (mapped != mem) {
1138 /* memory changed, lock new memory */
1139 gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (mapped),
1140 GST_MINI_OBJECT_CAST (buffer));
1141 gst_memory_lock (mapped, GST_LOCK_FLAG_EXCLUSIVE);
1142 GST_BUFFER_MEM_PTR (buffer, idx) = mapped;
1143 /* unlock old memory */
1144 gst_memory_unlock (mem, GST_LOCK_FLAG_EXCLUSIVE);
1145 gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (mem),
1146 GST_MINI_OBJECT_CAST (buffer));
1147 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
1149 gst_memory_unref (mem);
1155 * gst_buffer_peek_memory:
1156 * @buffer: a #GstBuffer.
1159 * Get the memory block at @idx in @buffer. The memory block stays valid until
1160 * the memory block in @buffer is removed, replaced or merged, typically with
1161 * any call that modifies the memory in @buffer.
1163 * Returns: (transfer none) (nullable): the #GstMemory at @idx.
1166 gst_buffer_peek_memory (GstBuffer * buffer, guint idx)
1168 g_return_val_if_fail (GST_IS_BUFFER (buffer), NULL);
1169 g_return_val_if_fail (idx < GST_BUFFER_MEM_LEN (buffer), NULL);
1171 return GST_BUFFER_MEM_PTR (buffer, idx);
1175 * gst_buffer_get_memory:
1176 * @buffer: a #GstBuffer.
1179 * Get the memory block at index @idx in @buffer.
1181 * Returns: (transfer full) (nullable): a #GstMemory that contains the data of the
1182 * memory block at @idx. Use gst_memory_unref () after usage.
1185 gst_buffer_get_memory (GstBuffer * buffer, guint idx)
1187 return gst_buffer_get_memory_range (buffer, idx, 1);
1191 * gst_buffer_get_all_memory:
1192 * @buffer: a #GstBuffer.
1194 * Get all the memory block in @buffer. The memory blocks will be merged
1195 * into one large #GstMemory.
1197 * Returns: (transfer full) (nullable): a #GstMemory that contains the merged memory.
1198 * Use gst_memory_unref () after usage.
1201 gst_buffer_get_all_memory (GstBuffer * buffer)
1203 return gst_buffer_get_memory_range (buffer, 0, -1);
1207 * gst_buffer_get_memory_range:
1208 * @buffer: a #GstBuffer.
1212 * Get @length memory blocks in @buffer starting at @idx. The memory blocks will
1213 * be merged into one large #GstMemory.
1215 * If @length is -1, all memory starting from @idx is merged.
1217 * Returns: (transfer full) (nullable): a #GstMemory that contains the merged data of @length
1218 * blocks starting at @idx. Use gst_memory_unref () after usage.
1221 gst_buffer_get_memory_range (GstBuffer * buffer, guint idx, gint length)
1225 GST_CAT_DEBUG (GST_CAT_BUFFER, "idx %u, length %d", idx, length);
1227 g_return_val_if_fail (GST_IS_BUFFER (buffer), NULL);
1228 len = GST_BUFFER_MEM_LEN (buffer);
1229 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1230 (length == -1 && idx < len) || (length > 0 && length + idx <= len), NULL);
1235 return _get_merged_memory (buffer, idx, length);
1239 * gst_buffer_replace_memory:
1240 * @buffer: a #GstBuffer.
1242 * @mem: (transfer full): a #GstMemory
1244 * Replaces the memory block at index @idx in @buffer with @mem.
1247 gst_buffer_replace_memory (GstBuffer * buffer, guint idx, GstMemory * mem)
1249 gst_buffer_replace_memory_range (buffer, idx, 1, mem);
1253 * gst_buffer_replace_all_memory:
1254 * @buffer: a #GstBuffer.
1255 * @mem: (transfer full): a #GstMemory
1257 * Replaces all memory in @buffer with @mem.
1260 gst_buffer_replace_all_memory (GstBuffer * buffer, GstMemory * mem)
1262 gst_buffer_replace_memory_range (buffer, 0, -1, mem);
1266 * gst_buffer_replace_memory_range:
1267 * @buffer: a #GstBuffer.
1269 * @length: a length should not be 0
1270 * @mem: (transfer full): a #GstMemory
1272 * Replaces @length memory blocks in @buffer starting at @idx with @mem.
1274 * If @length is -1, all memory starting from @idx will be removed and
1275 * replaced with @mem.
1277 * @buffer should be writable.
1280 gst_buffer_replace_memory_range (GstBuffer * buffer, guint idx, gint length,
1285 g_return_if_fail (GST_IS_BUFFER (buffer));
1286 g_return_if_fail (gst_buffer_is_writable (buffer));
1288 GST_CAT_DEBUG (GST_CAT_BUFFER, "idx %u, length %d, %p", idx, length, mem);
1290 len = GST_BUFFER_MEM_LEN (buffer);
1291 g_return_if_fail ((len == 0 && idx == 0 && length == -1) ||
1292 (length == -1 && idx < len) || (length > 0 && length + idx <= len));
1297 _replace_memory (buffer, len, idx, length, mem);
1301 * gst_buffer_remove_memory:
1302 * @buffer: a #GstBuffer.
1305 * Remove the memory block in @b at index @i.
1308 gst_buffer_remove_memory (GstBuffer * buffer, guint idx)
1310 gst_buffer_remove_memory_range (buffer, idx, 1);
1314 * gst_buffer_remove_all_memory:
1315 * @buffer: a #GstBuffer.
1317 * Remove all the memory blocks in @buffer.
1320 gst_buffer_remove_all_memory (GstBuffer * buffer)
1322 if (GST_BUFFER_MEM_LEN (buffer))
1323 gst_buffer_remove_memory_range (buffer, 0, -1);
1327 * gst_buffer_remove_memory_range:
1328 * @buffer: a #GstBuffer.
1332 * Remove @length memory blocks in @buffer starting from @idx.
1334 * @length can be -1, in which case all memory starting from @idx is removed.
1337 gst_buffer_remove_memory_range (GstBuffer * buffer, guint idx, gint length)
1341 g_return_if_fail (GST_IS_BUFFER (buffer));
1342 g_return_if_fail (gst_buffer_is_writable (buffer));
1344 GST_CAT_DEBUG (GST_CAT_BUFFER, "idx %u, length %d", idx, length);
1346 len = GST_BUFFER_MEM_LEN (buffer);
1347 g_return_if_fail ((len == 0 && idx == 0 && length == -1) ||
1348 (length == -1 && idx < len) || length + idx <= len);
1353 _replace_memory (buffer, len, idx, length, NULL);
1357 * gst_buffer_find_memory:
1358 * @buffer: a #GstBuffer.
1359 * @offset: an offset
1361 * @idx: (out): pointer to index
1362 * @length: (out): pointer to length
1363 * @skip: (out): pointer to skip
1365 * Find the memory blocks that span @size bytes starting from @offset
1368 * When this function returns %TRUE, @idx will contain the index of the first
1369 * memory block where the byte for @offset can be found and @length contains the
1370 * number of memory blocks containing the @size remaining bytes. @skip contains
1371 * the number of bytes to skip in the memory block at @idx to get to the byte
1374 * @size can be -1 to get all the memory blocks after @idx.
1376 * Returns: %TRUE when @size bytes starting from @offset could be found in
1377 * @buffer and @idx, @length and @skip will be filled.
1380 gst_buffer_find_memory (GstBuffer * buffer, gsize offset, gsize size,
1381 guint * idx, guint * length, gsize * skip)
1383 guint i, len, found;
1385 g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
1386 g_return_val_if_fail (idx != NULL, FALSE);
1387 g_return_val_if_fail (length != NULL, FALSE);
1388 g_return_val_if_fail (skip != NULL, FALSE);
1390 len = GST_BUFFER_MEM_LEN (buffer);
1393 for (i = 0; i < len; i++) {
1397 mem = GST_BUFFER_MEM_PTR (buffer, i);
1401 /* block before offset, or empty block, skip */
1404 /* block after offset */
1406 /* first block, remember index and offset */
1410 /* return remaining blocks */
1417 /* count the amount of found bytes */
1419 if (found >= size) {
1420 /* we have enough bytes */
1421 *length = i - *idx + 1;
1430 * gst_buffer_is_memory_range_writable:
1431 * @buffer: a #GstBuffer.
1433 * @length: a length should not be 0
1435 * Check if @length memory blocks in @buffer starting from @idx are writable.
1437 * @length can be -1 to check all the memory blocks after @idx.
1439 * Note that this function does not check if @buffer is writable, use
1440 * gst_buffer_is_writable() to check that if needed.
1442 * Returns: %TRUE if the memory range is writable
1447 gst_buffer_is_memory_range_writable (GstBuffer * buffer, guint idx, gint length)
1451 g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
1453 GST_CAT_DEBUG (GST_CAT_BUFFER, "idx %u, length %d", idx, length);
1455 len = GST_BUFFER_MEM_LEN (buffer);
1456 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1457 (length == -1 && idx < len) || (length > 0 && length + idx <= len),
1465 for (i = 0; i < len; i++) {
1466 if (!gst_memory_is_writable (GST_BUFFER_MEM_PTR (buffer, i + idx)))
1473 * gst_buffer_is_all_memory_writable:
1474 * @buffer: a #GstBuffer.
1476 * Check if all memory blocks in @buffer are writable.
1478 * Note that this function does not check if @buffer is writable, use
1479 * gst_buffer_is_writable() to check that if needed.
1481 * Returns: %TRUE if all memory blocks in @buffer are writable
1486 gst_buffer_is_all_memory_writable (GstBuffer * buffer)
1488 return gst_buffer_is_memory_range_writable (buffer, 0, -1);
1492 * gst_buffer_get_sizes:
1493 * @buffer: a #GstBuffer.
1494 * @offset: (out) (allow-none): a pointer to the offset
1495 * @maxsize: (out) (allow-none): a pointer to the maxsize
1497 * Get the total size of the memory blocks in @b.
1499 * When not %NULL, @offset will contain the offset of the data in the
1500 * first memory block in @buffer and @maxsize will contain the sum of
1501 * the size and @offset and the amount of extra padding on the last
1502 * memory block. @offset and @maxsize can be used to resize the
1503 * buffer memory blocks with gst_buffer_resize().
1505 * Returns: total size of the memory blocks in @buffer.
1508 gst_buffer_get_sizes (GstBuffer * buffer, gsize * offset, gsize * maxsize)
1510 return gst_buffer_get_sizes_range (buffer, 0, -1, offset, maxsize);
1514 * gst_buffer_get_size:
1515 * @buffer: a #GstBuffer.
1517 * Get the total size of the memory blocks in @buffer.
1519 * Returns: total size of the memory blocks in @buffer.
1522 gst_buffer_get_size (GstBuffer * buffer)
1527 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1530 len = GST_BUFFER_MEM_LEN (buffer);
1531 for (i = 0, size = 0; i < len; i++)
1532 size += GST_BUFFER_MEM_PTR (buffer, i)->size;
1537 * gst_buffer_get_sizes_range:
1538 * @buffer: a #GstBuffer.
1541 * @offset: (out) (allow-none): a pointer to the offset
1542 * @maxsize: (out) (allow-none): a pointer to the maxsize
1544 * Get the total size of @length memory blocks stating from @idx in @buffer.
1546 * When not %NULL, @offset will contain the offset of the data in the
1547 * memory block in @buffer at @idx and @maxsize will contain the sum of the size
1548 * and @offset and the amount of extra padding on the memory block at @idx +
1550 * @offset and @maxsize can be used to resize the buffer memory blocks with
1551 * gst_buffer_resize_range().
1553 * Returns: total size of @length memory blocks starting at @idx in @buffer.
1556 gst_buffer_get_sizes_range (GstBuffer * buffer, guint idx, gint length,
1557 gsize * offset, gsize * maxsize)
1563 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1564 len = GST_BUFFER_MEM_LEN (buffer);
1565 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1566 (length == -1 && idx < len) || (length + idx <= len), 0);
1571 if (G_LIKELY (length == 1)) {
1573 mem = GST_BUFFER_MEM_PTR (buffer, idx);
1574 size = gst_memory_get_sizes (mem, offset, maxsize);
1575 } else if (offset == NULL && maxsize == NULL) {
1581 for (i = idx; i < end; i++) {
1582 mem = GST_BUFFER_MEM_PTR (buffer, i);
1590 size = offs = extra = 0;
1591 for (i = idx; i < end; i++) {
1594 mem = GST_BUFFER_MEM_PTR (buffer, i);
1595 s = gst_memory_get_sizes (mem, &o, &ms);
1599 /* first size, take accumulated data before as the offset */
1603 /* save the amount of data after this block */
1604 extra = ms - (o + s);
1606 /* empty block, add as extra */
1613 *maxsize = offs + size + extra;
1619 * gst_buffer_resize:
1620 * @buffer: a #GstBuffer.
1621 * @offset: the offset adjustment
1622 * @size: the new size or -1 to just adjust the offset
1624 * Set the offset and total size of the memory blocks in @buffer.
1627 gst_buffer_resize (GstBuffer * buffer, gssize offset, gssize size)
1629 gst_buffer_resize_range (buffer, 0, -1, offset, size);
1633 * gst_buffer_set_size:
1634 * @buffer: a #GstBuffer.
1635 * @size: the new size
1637 * Set the total size of the memory blocks in @buffer.
1640 gst_buffer_set_size (GstBuffer * buffer, gssize size)
1642 gst_buffer_resize_range (buffer, 0, -1, 0, size);
1646 * gst_buffer_resize_range:
1647 * @buffer: a #GstBuffer.
1650 * @offset: the offset adjustment
1651 * @size: the new size or -1 to just adjust the offset
1653 * Set the total size of the @length memory blocks starting at @idx in
1656 * Returns: %TRUE if resizing succeeded, %FALSE otherwise.
1659 gst_buffer_resize_range (GstBuffer * buffer, guint idx, gint length,
1660 gssize offset, gssize size)
1663 gsize bsize, bufsize, bufoffs, bufmax;
1665 g_return_val_if_fail (gst_buffer_is_writable (buffer), FALSE);
1666 g_return_val_if_fail (size >= -1, FALSE);
1668 len = GST_BUFFER_MEM_LEN (buffer);
1669 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1670 (length == -1 && idx < len) || (length + idx <= len), FALSE);
1675 bufsize = gst_buffer_get_sizes_range (buffer, idx, length, &bufoffs, &bufmax);
1677 GST_CAT_LOG (GST_CAT_BUFFER, "trim %p %" G_GSSIZE_FORMAT "-%" G_GSSIZE_FORMAT
1678 " size:%" G_GSIZE_FORMAT " offs:%" G_GSIZE_FORMAT " max:%"
1679 G_GSIZE_FORMAT, buffer, offset, size, bufsize, bufoffs, bufmax);
1681 /* we can't go back further than the current offset or past the end of the
1683 g_return_val_if_fail ((offset < 0 && bufoffs >= -offset) || (offset >= 0
1684 && bufoffs + offset <= bufmax), FALSE);
1686 g_return_val_if_fail (bufsize >= offset, FALSE);
1687 size = bufsize - offset;
1689 g_return_val_if_fail (bufmax >= bufoffs + offset + size, FALSE);
1692 if (offset == 0 && size == bufsize)
1697 for (i = idx; i < end; i++) {
1701 mem = GST_BUFFER_MEM_PTR (buffer, i);
1705 /* last buffer always gets resized to the remaining size */
1708 /* shrink buffers before the offset */
1709 else if ((gssize) bsize <= offset) {
1711 noffs = offset - bsize;
1714 /* clip other buffers */
1716 left = MIN (bsize - offset, size);
1718 if (offset != 0 || left != bsize) {
1719 if (gst_memory_is_writable (mem)) {
1720 gst_memory_resize (mem, offset, left);
1722 GstMemory *newmem = NULL;
1724 if (!GST_MEMORY_IS_NO_SHARE (mem))
1725 newmem = gst_memory_share (mem, offset, left);
1728 newmem = gst_memory_copy (mem, offset, left);
1733 gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (newmem),
1734 GST_MINI_OBJECT_CAST (buffer));
1735 gst_memory_lock (newmem, GST_LOCK_FLAG_EXCLUSIVE);
1736 GST_BUFFER_MEM_PTR (buffer, i) = newmem;
1737 gst_memory_unlock (mem, GST_LOCK_FLAG_EXCLUSIVE);
1738 gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (mem),
1739 GST_MINI_OBJECT_CAST (buffer));
1740 gst_memory_unref (mem);
1742 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
1755 * @buffer: a #GstBuffer.
1756 * @info: (out): info about the mapping
1757 * @flags: flags for the mapping
1759 * This function fills @info with the #GstMapInfo of all merged memory
1760 * blocks in @buffer.
1762 * @flags describe the desired access of the memory. When @flags is
1763 * #GST_MAP_WRITE, @buffer should be writable (as returned from
1764 * gst_buffer_is_writable()).
1766 * When @buffer is writable but the memory isn't, a writable copy will
1767 * automatically be created and returned. The readonly copy of the
1768 * buffer memory will then also be replaced with this writable copy.
1770 * The memory in @info should be unmapped with gst_buffer_unmap() after
1773 * Returns: %TRUE if the map succeeded and @info contains valid data.
1776 gst_buffer_map (GstBuffer * buffer, GstMapInfo * info, GstMapFlags flags)
1778 return gst_buffer_map_range (buffer, 0, -1, info, flags);
1782 * gst_buffer_map_range:
1783 * @buffer: a #GstBuffer.
1786 * @info: (out): info about the mapping
1787 * @flags: flags for the mapping
1789 * This function fills @info with the #GstMapInfo of @length merged memory blocks
1790 * starting at @idx in @buffer. When @length is -1, all memory blocks starting
1791 * from @idx are merged and mapped.
1793 * @flags describe the desired access of the memory. When @flags is
1794 * #GST_MAP_WRITE, @buffer should be writable (as returned from
1795 * gst_buffer_is_writable()).
1797 * When @buffer is writable but the memory isn't, a writable copy will
1798 * automatically be created and returned. The readonly copy of the buffer memory
1799 * will then also be replaced with this writable copy.
1801 * The memory in @info should be unmapped with gst_buffer_unmap() after usage.
1803 * Returns: %TRUE if the map succeeded and @info contains valid
1807 gst_buffer_map_range (GstBuffer * buffer, guint idx, gint length,
1808 GstMapInfo * info, GstMapFlags flags)
1810 GstMemory *mem, *nmem;
1811 gboolean write, writable;
1814 g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
1815 g_return_val_if_fail (info != NULL, FALSE);
1816 len = GST_BUFFER_MEM_LEN (buffer);
1817 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1818 (length == -1 && idx < len) || (length > 0
1819 && length + idx <= len), FALSE);
1821 GST_CAT_LOG (GST_CAT_BUFFER, "buffer %p, idx %u, length %d, flags %04x",
1822 buffer, idx, length, flags);
1824 write = (flags & GST_MAP_WRITE) != 0;
1825 writable = gst_buffer_is_writable (buffer);
1827 /* check if we can write when asked for write access */
1828 if (G_UNLIKELY (write && !writable))
1834 mem = _get_merged_memory (buffer, idx, length);
1835 if (G_UNLIKELY (mem == NULL))
1838 /* now try to map */
1839 nmem = gst_memory_make_mapped (mem, info, flags);
1840 if (G_UNLIKELY (nmem == NULL))
1843 /* if we merged or when the map returned a different memory, we try to replace
1844 * the memory in the buffer */
1845 if (G_UNLIKELY (length > 1 || nmem != mem)) {
1846 /* if the buffer is writable, replace the memory */
1848 _replace_memory (buffer, len, idx, length, gst_memory_ref (nmem));
1851 GST_CAT_DEBUG (GST_CAT_PERFORMANCE,
1852 "temporary mapping for memory %p in buffer %p", nmem, buffer);
1861 GST_WARNING ("write map requested on non-writable buffer");
1862 g_critical ("write map requested on non-writable buffer");
1863 memset (info, 0, sizeof (GstMapInfo));
1868 /* empty buffer, we need to return NULL */
1869 GST_DEBUG ("can't get buffer memory");
1870 memset (info, 0, sizeof (GstMapInfo));
1875 GST_DEBUG ("cannot map memory");
1876 memset (info, 0, sizeof (GstMapInfo));
1883 * @buffer: a #GstBuffer.
1884 * @info: a #GstMapInfo
1886 * Release the memory previously mapped with gst_buffer_map().
1889 gst_buffer_unmap (GstBuffer * buffer, GstMapInfo * info)
1891 g_return_if_fail (GST_IS_BUFFER (buffer));
1892 g_return_if_fail (info != NULL);
1894 /* we need to check for NULL, it is possible that we tried to map a buffer
1895 * without memory and we should be able to unmap that fine */
1896 if (G_LIKELY (info->memory)) {
1897 gst_memory_unmap (info->memory, info);
1898 gst_memory_unref (info->memory);
1904 * @buffer: a #GstBuffer.
1905 * @offset: the offset to fill
1906 * @src: (array length=size) (element-type guint8): the source address
1907 * @size: the size to fill
1909 * Copy @size bytes from @src to @buffer at @offset.
1911 * Returns: The amount of bytes copied. This value can be lower than @size
1912 * when @buffer did not contain enough data.
1915 gst_buffer_fill (GstBuffer * buffer, gsize offset, gconstpointer src,
1919 const guint8 *ptr = src;
1921 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1922 g_return_val_if_fail (gst_buffer_is_writable (buffer), 0);
1923 g_return_val_if_fail (src != NULL || size == 0, 0);
1925 GST_CAT_LOG (GST_CAT_BUFFER,
1926 "buffer %p, offset %" G_GSIZE_FORMAT ", size %" G_GSIZE_FORMAT, buffer,
1929 len = GST_BUFFER_MEM_LEN (buffer);
1932 for (i = 0; i < len && left > 0; i++) {
1937 mem = _get_mapped (buffer, i, &info, GST_MAP_WRITE);
1938 if (info.size > offset) {
1939 /* we have enough */
1940 tocopy = MIN (info.size - offset, left);
1941 memcpy ((guint8 *) info.data + offset, ptr, tocopy);
1946 /* offset past buffer, skip */
1947 offset -= info.size;
1949 gst_memory_unmap (mem, &info);
1955 * gst_buffer_extract:
1956 * @buffer: a #GstBuffer.
1957 * @offset: the offset to extract
1958 * @dest: (out caller-allocates) (array length=size) (element-type guint8):
1959 * the destination address
1960 * @size: the size to extract
1962 * Copy @size bytes starting from @offset in @buffer to @dest.
1964 * Returns: The amount of bytes extracted. This value can be lower than @size
1965 * when @buffer did not contain enough data.
1968 gst_buffer_extract (GstBuffer * buffer, gsize offset, gpointer dest, gsize size)
1973 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1974 g_return_val_if_fail (dest != NULL, 0);
1976 GST_CAT_LOG (GST_CAT_BUFFER,
1977 "buffer %p, offset %" G_GSIZE_FORMAT ", size %" G_GSIZE_FORMAT, buffer,
1980 len = GST_BUFFER_MEM_LEN (buffer);
1983 for (i = 0; i < len && left > 0; i++) {
1988 mem = _get_mapped (buffer, i, &info, GST_MAP_READ);
1989 if (info.size > offset) {
1990 /* we have enough */
1991 tocopy = MIN (info.size - offset, left);
1992 memcpy (ptr, (guint8 *) info.data + offset, tocopy);
1997 /* offset past buffer, skip */
1998 offset -= info.size;
2000 gst_memory_unmap (mem, &info);
2006 * gst_buffer_memcmp:
2007 * @buffer: a #GstBuffer.
2008 * @offset: the offset in @buffer
2009 * @mem: (array length=size) (element-type guint8): the memory to compare
2010 * @size: the size to compare
2012 * Compare @size bytes starting from @offset in @buffer with the memory in @mem.
2014 * Returns: 0 if the memory is equal.
2017 gst_buffer_memcmp (GstBuffer * buffer, gsize offset, gconstpointer mem,
2021 const guint8 *ptr = mem;
2024 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
2025 g_return_val_if_fail (mem != NULL, 0);
2027 GST_CAT_LOG (GST_CAT_BUFFER,
2028 "buffer %p, offset %" G_GSIZE_FORMAT ", size %" G_GSIZE_FORMAT, buffer,
2031 if (G_UNLIKELY (gst_buffer_get_size (buffer) < offset + size))
2034 len = GST_BUFFER_MEM_LEN (buffer);
2036 for (i = 0; i < len && size > 0 && res == 0; i++) {
2041 mem = _get_mapped (buffer, i, &info, GST_MAP_READ);
2042 if (info.size > offset) {
2043 /* we have enough */
2044 tocmp = MIN (info.size - offset, size);
2045 res = memcmp (ptr, (guint8 *) info.data + offset, tocmp);
2050 /* offset past buffer, skip */
2051 offset -= info.size;
2053 gst_memory_unmap (mem, &info);
2059 * gst_buffer_memset:
2060 * @buffer: a #GstBuffer.
2061 * @offset: the offset in @buffer
2062 * @val: the value to set
2063 * @size: the size to set
2065 * Fill @buf with @size bytes with @val starting from @offset.
2067 * Returns: The amount of bytes filled. This value can be lower than @size
2068 * when @buffer did not contain enough data.
2071 gst_buffer_memset (GstBuffer * buffer, gsize offset, guint8 val, gsize size)
2075 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
2076 g_return_val_if_fail (gst_buffer_is_writable (buffer), 0);
2078 GST_CAT_LOG (GST_CAT_BUFFER,
2079 "buffer %p, offset %" G_GSIZE_FORMAT ", val %02x, size %" G_GSIZE_FORMAT,
2080 buffer, offset, val, size);
2082 len = GST_BUFFER_MEM_LEN (buffer);
2085 for (i = 0; i < len && left > 0; i++) {
2090 mem = _get_mapped (buffer, i, &info, GST_MAP_WRITE);
2091 if (info.size > offset) {
2092 /* we have enough */
2093 toset = MIN (info.size - offset, left);
2094 memset ((guint8 *) info.data + offset, val, toset);
2098 /* offset past buffer, skip */
2099 offset -= info.size;
2101 gst_memory_unmap (mem, &info);
2107 * gst_buffer_copy_region:
2108 * @parent: a #GstBuffer.
2109 * @flags: the #GstBufferCopyFlags
2110 * @offset: the offset into parent #GstBuffer at which the new sub-buffer
2112 * @size: the size of the new #GstBuffer sub-buffer, in bytes. If -1, all
2115 * Creates a sub-buffer from @parent at @offset and @size.
2116 * This sub-buffer uses the actual memory space of the parent buffer.
2117 * This function will copy the offset and timestamp fields when the
2118 * offset is 0. If not, they will be set to #GST_CLOCK_TIME_NONE and
2119 * #GST_BUFFER_OFFSET_NONE.
2120 * If @offset equals 0 and @size equals the total size of @buffer, the
2121 * duration and offset end fields are also copied. If not they will be set
2122 * to #GST_CLOCK_TIME_NONE and #GST_BUFFER_OFFSET_NONE.
2126 * Returns: (transfer full): the new #GstBuffer or %NULL if the arguments were
2130 gst_buffer_copy_region (GstBuffer * buffer, GstBufferCopyFlags flags,
2131 gsize offset, gsize size)
2135 g_return_val_if_fail (buffer != NULL, NULL);
2137 /* create the new buffer */
2138 copy = gst_buffer_new ();
2140 GST_CAT_LOG (GST_CAT_BUFFER, "new region copy %p of %p %" G_GSIZE_FORMAT
2141 "-%" G_GSIZE_FORMAT, copy, buffer, offset, size);
2143 if (!gst_buffer_copy_into (copy, buffer, flags, offset, size))
2144 gst_buffer_replace (©, NULL);
2150 * gst_buffer_append:
2151 * @buf1: (transfer full): the first source #GstBuffer to append.
2152 * @buf2: (transfer full): the second source #GstBuffer to append.
2154 * Append all the memory from @buf2 to @buf1. The result buffer will contain a
2155 * concatenation of the memory of @buf1 and @buf2.
2157 * Returns: (transfer full): the new #GstBuffer that contains the memory
2158 * of the two source buffers.
2161 gst_buffer_append (GstBuffer * buf1, GstBuffer * buf2)
2163 return gst_buffer_append_region (buf1, buf2, 0, -1);
2167 * gst_buffer_append_region:
2168 * @buf1: (transfer full): the first source #GstBuffer to append.
2169 * @buf2: (transfer full): the second source #GstBuffer to append.
2170 * @offset: the offset in @buf2
2171 * @size: the size or -1 of @buf2
2173 * Append @size bytes at @offset from @buf2 to @buf1. The result buffer will
2174 * contain a concatenation of the memory of @buf1 and the requested region of
2177 * Returns: (transfer full): the new #GstBuffer that contains the memory
2178 * of the two source buffers.
2181 gst_buffer_append_region (GstBuffer * buf1, GstBuffer * buf2, gssize offset,
2186 g_return_val_if_fail (GST_IS_BUFFER (buf1), NULL);
2187 g_return_val_if_fail (GST_IS_BUFFER (buf2), NULL);
2189 buf1 = gst_buffer_make_writable (buf1);
2190 buf2 = gst_buffer_make_writable (buf2);
2192 gst_buffer_resize (buf2, offset, size);
2194 len = GST_BUFFER_MEM_LEN (buf2);
2195 for (i = 0; i < len; i++) {
2198 mem = GST_BUFFER_MEM_PTR (buf2, i);
2199 gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (mem),
2200 GST_MINI_OBJECT_CAST (buf2));
2201 GST_BUFFER_MEM_PTR (buf2, i) = NULL;
2202 _memory_add (buf1, -1, mem);
2205 GST_BUFFER_MEM_LEN (buf2) = 0;
2206 GST_BUFFER_FLAG_SET (buf2, GST_BUFFER_FLAG_TAG_MEMORY);
2207 gst_buffer_unref (buf2);
2213 * gst_buffer_get_meta:
2214 * @buffer: a #GstBuffer
2215 * @api: the #GType of an API
2217 * Get the metadata for @api on buffer. When there is no such metadata, %NULL is
2218 * returned. If multiple metadata with the given @api are attached to this
2219 * buffer only the first one is returned. To handle multiple metadata with a
2220 * given API use gst_buffer_iterate_meta() or gst_buffer_foreach_meta() instead
2221 * and check the meta->info.api member for the API type.
2223 * Returns: (transfer none) (nullable): the metadata for @api on
2227 gst_buffer_get_meta (GstBuffer * buffer, GType api)
2230 GstMeta *result = NULL;
2232 g_return_val_if_fail (buffer != NULL, NULL);
2233 g_return_val_if_fail (api != 0, NULL);
2235 /* find GstMeta of the requested API */
2236 for (item = GST_BUFFER_META (buffer); item; item = item->next) {
2237 GstMeta *meta = &item->meta;
2238 if (meta->info->api == api) {
2247 * gst_buffer_get_n_meta:
2248 * @buffer: a #GstBuffer
2249 * @api_type: the #GType of an API
2251 * Returns: number of metas of type @api_type on @buffer.
2256 gst_buffer_get_n_meta (GstBuffer * buffer, GType api_type)
2258 gpointer state = NULL;
2262 while ((meta = gst_buffer_iterate_meta_filtered (buffer, &state, api_type)))
2269 * gst_buffer_add_meta:
2270 * @buffer: a #GstBuffer
2271 * @info: a #GstMetaInfo
2272 * @params: params for @info
2274 * Add metadata for @info to @buffer using the parameters in @params.
2276 * Returns: (transfer none) (nullable): the metadata for the api in @info on @buffer.
2279 gst_buffer_add_meta (GstBuffer * buffer, const GstMetaInfo * info,
2283 GstMeta *result = NULL;
2286 g_return_val_if_fail (buffer != NULL, NULL);
2287 g_return_val_if_fail (info != NULL, NULL);
2288 g_return_val_if_fail (gst_buffer_is_writable (buffer), NULL);
2290 /* create a new slice */
2291 size = ITEM_SIZE (info);
2292 /* We warn in gst_meta_register() about metas without
2293 * init function but let's play safe here and prevent
2294 * uninitialized memory
2296 if (!info->init_func)
2297 item = g_slice_alloc0 (size);
2299 item = g_slice_alloc (size);
2300 result = &item->meta;
2301 result->info = info;
2302 result->flags = GST_META_FLAG_NONE;
2303 GST_CAT_DEBUG (GST_CAT_BUFFER,
2304 "alloc metadata %p (%s) of size %" G_GSIZE_FORMAT, result,
2305 g_type_name (info->type), info->size);
2307 /* call the init_func when needed */
2308 if (info->init_func)
2309 if (!info->init_func (result, params, buffer))
2312 item->seq_num = gst_atomic_int64_inc (&meta_seq);
2315 if (!GST_BUFFER_META (buffer)) {
2316 GST_BUFFER_META (buffer) = item;
2317 GST_BUFFER_TAIL_META (buffer) = item;
2319 GST_BUFFER_TAIL_META (buffer)->next = item;
2320 GST_BUFFER_TAIL_META (buffer) = item;
2327 g_slice_free1 (size, item);
2333 * gst_buffer_remove_meta:
2334 * @buffer: a #GstBuffer
2337 * Remove the metadata for @meta on @buffer.
2339 * Returns: %TRUE if the metadata existed and was removed, %FALSE if no such
2340 * metadata was on @buffer.
2343 gst_buffer_remove_meta (GstBuffer * buffer, GstMeta * meta)
2345 GstMetaItem *walk, *prev;
2347 g_return_val_if_fail (buffer != NULL, FALSE);
2348 g_return_val_if_fail (meta != NULL, FALSE);
2349 g_return_val_if_fail (gst_buffer_is_writable (buffer), FALSE);
2350 g_return_val_if_fail (!GST_META_FLAG_IS_SET (meta, GST_META_FLAG_LOCKED),
2353 /* find the metadata and delete */
2354 prev = GST_BUFFER_META (buffer);
2355 for (walk = prev; walk; walk = walk->next) {
2356 GstMeta *m = &walk->meta;
2358 const GstMetaInfo *info = meta->info;
2360 /* remove from list */
2361 if (GST_BUFFER_TAIL_META (buffer) == walk) {
2363 GST_BUFFER_TAIL_META (buffer) = prev;
2365 GST_BUFFER_TAIL_META (buffer) = NULL;
2368 if (GST_BUFFER_META (buffer) == walk)
2369 GST_BUFFER_META (buffer) = walk->next;
2371 prev->next = walk->next;
2373 /* call free_func if any */
2374 if (info->free_func)
2375 info->free_func (m, buffer);
2377 /* and free the slice */
2378 g_slice_free1 (ITEM_SIZE (info), walk);
2383 return walk != NULL;
2387 * gst_buffer_iterate_meta: (skip)
2388 * @buffer: a #GstBuffer
2389 * @state: (out caller-allocates): an opaque state pointer
2391 * Retrieve the next #GstMeta after @current. If @state points
2392 * to %NULL, the first metadata is returned.
2394 * @state will be updated with an opaque state pointer
2396 * Returns: (transfer none) (nullable): The next #GstMeta or %NULL
2397 * when there are no more items.
2400 gst_buffer_iterate_meta (GstBuffer * buffer, gpointer * state)
2404 g_return_val_if_fail (buffer != NULL, NULL);
2405 g_return_val_if_fail (state != NULL, NULL);
2407 meta = (GstMetaItem **) state;
2409 /* state NULL, move to first item */
2410 *meta = GST_BUFFER_META (buffer);
2412 /* state !NULL, move to next item in list */
2413 *meta = (*meta)->next;
2416 return &(*meta)->meta;
2422 * gst_buffer_iterate_meta_filtered: (skip)
2423 * @buffer: a #GstBuffer
2424 * @state: (out caller-allocates): an opaque state pointer
2425 * @meta_api_type: only return #GstMeta of this type
2427 * Retrieve the next #GstMeta of type @meta_api_type after the current one
2428 * according to @state. If @state points to %NULL, the first metadata of
2429 * type @meta_api_type is returned.
2431 * @state will be updated with an opaque state pointer
2433 * Returns: (transfer none) (nullable): The next #GstMeta of type
2434 * @meta_api_type or %NULL when there are no more items.
2439 gst_buffer_iterate_meta_filtered (GstBuffer * buffer, gpointer * state,
2440 GType meta_api_type)
2444 g_return_val_if_fail (buffer != NULL, NULL);
2445 g_return_val_if_fail (state != NULL, NULL);
2447 meta = (GstMetaItem **) state;
2449 /* state NULL, move to first item */
2450 *meta = GST_BUFFER_META (buffer);
2452 /* state !NULL, move to next item in list */
2453 *meta = (*meta)->next;
2455 while (*meta != NULL && (*meta)->meta.info->api != meta_api_type)
2456 *meta = (*meta)->next;
2459 return &(*meta)->meta;
2465 * gst_buffer_foreach_meta:
2466 * @buffer: a #GstBuffer
2467 * @func: (scope call): a #GstBufferForeachMetaFunc to call
2468 * @user_data: (closure): user data passed to @func
2470 * Call @func with @user_data for each meta in @buffer.
2472 * @func can modify the passed meta pointer or its contents. The return value
2473 * of @func define if this function returns or if the remaining metadata items
2474 * in the buffer should be skipped.
2476 * Returns: %FALSE when @func returned %FALSE for one of the metadata.
2479 gst_buffer_foreach_meta (GstBuffer * buffer, GstBufferForeachMetaFunc func,
2482 GstMetaItem *walk, *prev, *next;
2483 gboolean res = TRUE;
2485 g_return_val_if_fail (buffer != NULL, FALSE);
2486 g_return_val_if_fail (func != NULL, FALSE);
2488 /* find the metadata and delete */
2489 prev = GST_BUFFER_META (buffer);
2490 for (walk = prev; walk; walk = next) {
2493 m = new = &walk->meta;
2496 res = func (buffer, &new, user_data);
2499 const GstMetaInfo *info = m->info;
2501 GST_CAT_DEBUG (GST_CAT_BUFFER, "remove metadata %p (%s)", m,
2502 g_type_name (info->type));
2504 g_return_val_if_fail (gst_buffer_is_writable (buffer), FALSE);
2505 g_return_val_if_fail (!GST_META_FLAG_IS_SET (m, GST_META_FLAG_LOCKED),
2508 if (GST_BUFFER_TAIL_META (buffer) == walk) {
2510 GST_BUFFER_TAIL_META (buffer) = prev;
2512 GST_BUFFER_TAIL_META (buffer) = NULL;
2515 /* remove from list */
2516 if (GST_BUFFER_META (buffer) == walk)
2517 prev = GST_BUFFER_META (buffer) = next;
2521 /* call free_func if any */
2522 if (info->free_func)
2523 info->free_func (m, buffer);
2525 /* and free the slice */
2526 g_slice_free1 (ITEM_SIZE (info), walk);
2537 * gst_buffer_extract_dup:
2538 * @buffer: a #GstBuffer
2539 * @offset: the offset to extract
2540 * @size: the size to extract
2541 * @dest: (array length=dest_size) (element-type guint8) (out): A pointer where
2542 * the destination array will be written. Might be %NULL if the size is 0.
2543 * @dest_size: (out): A location where the size of @dest can be written
2545 * Extracts a copy of at most @size bytes the data at @offset into
2546 * newly-allocated memory. @dest must be freed using g_free() when done.
2552 gst_buffer_extract_dup (GstBuffer * buffer, gsize offset, gsize size,
2553 gpointer * dest, gsize * dest_size)
2555 gsize real_size, alloc_size;
2557 real_size = gst_buffer_get_size (buffer);
2559 alloc_size = MIN (real_size - offset, size);
2560 if (alloc_size == 0) {
2564 *dest = g_malloc (alloc_size);
2565 *dest_size = gst_buffer_extract (buffer, offset, *dest, size);
2569 GST_DEBUG_CATEGORY_STATIC (gst_parent_buffer_meta_debug);
2572 * gst_buffer_add_parent_buffer_meta:
2573 * @buffer: (transfer none): a #GstBuffer
2574 * @ref: (transfer none): a #GstBuffer to ref
2576 * Add a #GstParentBufferMeta to @buffer that holds a reference on
2577 * @ref until the buffer is freed.
2579 * Returns: (transfer none) (nullable): The #GstParentBufferMeta that was added to the buffer
2583 GstParentBufferMeta *
2584 gst_buffer_add_parent_buffer_meta (GstBuffer * buffer, GstBuffer * ref)
2586 GstParentBufferMeta *meta;
2588 g_return_val_if_fail (GST_IS_BUFFER (ref), NULL);
2591 (GstParentBufferMeta *) gst_buffer_add_meta (buffer,
2592 GST_PARENT_BUFFER_META_INFO, NULL);
2597 meta->buffer = gst_buffer_ref (ref);
2603 _gst_parent_buffer_meta_transform (GstBuffer * dest, GstMeta * meta,
2604 GstBuffer * buffer, GQuark type, gpointer data)
2606 GstParentBufferMeta *dmeta, *smeta;
2608 smeta = (GstParentBufferMeta *) meta;
2610 if (GST_META_TRANSFORM_IS_COPY (type)) {
2611 /* copy over the reference to the parent buffer.
2612 * Usually, this meta means we need to keep the parent buffer
2613 * alive because one of the child memories is in use, which
2614 * might not be the case if memory is deep copied or sub-regioned,
2615 * but we can't tell, so keep the meta */
2616 dmeta = gst_buffer_add_parent_buffer_meta (dest, smeta->buffer);
2620 GST_CAT_DEBUG (gst_parent_buffer_meta_debug,
2621 "copy buffer reference metadata");
2623 /* return FALSE, if transform type is not supported */
2630 _gst_parent_buffer_meta_free (GstParentBufferMeta * parent_meta,
2633 GST_CAT_DEBUG (gst_parent_buffer_meta_debug,
2634 "Dropping reference on buffer %p", parent_meta->buffer);
2635 gst_buffer_unref (parent_meta->buffer);
2639 _gst_parent_buffer_meta_init (GstParentBufferMeta * parent_meta,
2640 gpointer params, GstBuffer * buffer)
2642 static volatile gsize _init;
2644 if (g_once_init_enter (&_init)) {
2645 GST_DEBUG_CATEGORY_INIT (gst_parent_buffer_meta_debug, "parentbuffermeta",
2646 0, "parentbuffermeta");
2647 g_once_init_leave (&_init, 1);
2650 parent_meta->buffer = NULL;
2656 * gst_parent_buffer_meta_api_get_type: (attributes doc.skip=true)
2659 gst_parent_buffer_meta_api_get_type (void)
2661 static volatile GType type = 0;
2662 static const gchar *tags[] = { NULL };
2664 if (g_once_init_enter (&type)) {
2665 GType _type = gst_meta_api_type_register ("GstParentBufferMetaAPI", tags);
2666 g_once_init_leave (&type, _type);
2673 * gst_parent_buffer_meta_get_info:
2675 * Get the global #GstMetaInfo describing the #GstParentBufferMeta meta.
2677 * Returns: (transfer none): The #GstMetaInfo
2682 gst_parent_buffer_meta_get_info (void)
2684 static const GstMetaInfo *meta_info = NULL;
2686 if (g_once_init_enter ((GstMetaInfo **) & meta_info)) {
2687 const GstMetaInfo *meta =
2688 gst_meta_register (gst_parent_buffer_meta_api_get_type (),
2689 "GstParentBufferMeta",
2690 sizeof (GstParentBufferMeta),
2691 (GstMetaInitFunction) _gst_parent_buffer_meta_init,
2692 (GstMetaFreeFunction) _gst_parent_buffer_meta_free,
2693 _gst_parent_buffer_meta_transform);
2694 g_once_init_leave ((GstMetaInfo **) & meta_info, (GstMetaInfo *) meta);
2700 GST_DEBUG_CATEGORY_STATIC (gst_reference_timestamp_meta_debug);
2703 * gst_buffer_add_reference_timestamp_meta:
2704 * @buffer: (transfer none): a #GstBuffer
2705 * @reference: (transfer none): identifier for the timestamp reference.
2706 * @timestamp: timestamp
2707 * @duration: duration, or %GST_CLOCK_TIME_NONE
2709 * Add a #GstReferenceTimestampMeta to @buffer that holds a @timestamp and
2710 * optionally @duration based on a specific timestamp @reference. See the
2711 * documentation of #GstReferenceTimestampMeta for details.
2713 * Returns: (transfer none) (nullable): The #GstReferenceTimestampMeta that was added to the buffer
2717 GstReferenceTimestampMeta *
2718 gst_buffer_add_reference_timestamp_meta (GstBuffer * buffer,
2719 GstCaps * reference, GstClockTime timestamp, GstClockTime duration)
2721 GstReferenceTimestampMeta *meta;
2723 g_return_val_if_fail (GST_IS_CAPS (reference), NULL);
2724 g_return_val_if_fail (timestamp != GST_CLOCK_TIME_NONE, NULL);
2727 (GstReferenceTimestampMeta *) gst_buffer_add_meta (buffer,
2728 GST_REFERENCE_TIMESTAMP_META_INFO, NULL);
2733 meta->reference = gst_caps_ref (reference);
2734 meta->timestamp = timestamp;
2735 meta->duration = duration;
2741 * gst_buffer_get_reference_timestamp_meta:
2742 * @buffer: a #GstBuffer
2743 * @reference: (allow-none): a reference #GstCaps
2745 * Find the first #GstReferenceTimestampMeta on @buffer that conforms to
2746 * @reference. Conformance is tested by checking if the meta's reference is a
2747 * subset of @reference.
2749 * Buffers can contain multiple #GstReferenceTimestampMeta metadata items.
2751 * Returns: (transfer none) (nullable): the #GstReferenceTimestampMeta or %NULL when there
2752 * is no such metadata on @buffer.
2756 GstReferenceTimestampMeta *
2757 gst_buffer_get_reference_timestamp_meta (GstBuffer * buffer,
2758 GstCaps * reference)
2760 gpointer state = NULL;
2762 const GstMetaInfo *info = GST_REFERENCE_TIMESTAMP_META_INFO;
2764 while ((meta = gst_buffer_iterate_meta (buffer, &state))) {
2765 if (meta->info->api == info->api) {
2766 GstReferenceTimestampMeta *rmeta = (GstReferenceTimestampMeta *) meta;
2770 if (gst_caps_is_subset (rmeta->reference, reference))
2778 _gst_reference_timestamp_meta_transform (GstBuffer * dest, GstMeta * meta,
2779 GstBuffer * buffer, GQuark type, gpointer data)
2781 GstReferenceTimestampMeta *dmeta, *smeta;
2783 /* we copy over the reference timestamp meta, independent of transformation
2784 * that happens. If it applied to the original buffer, it still applies to
2785 * the new buffer as it refers to the time when the media was captured */
2786 smeta = (GstReferenceTimestampMeta *) meta;
2788 gst_buffer_add_reference_timestamp_meta (dest, smeta->reference,
2789 smeta->timestamp, smeta->duration);
2793 GST_CAT_DEBUG (gst_reference_timestamp_meta_debug,
2794 "copy reference timestamp metadata from buffer %p to %p", buffer, dest);
2800 _gst_reference_timestamp_meta_free (GstReferenceTimestampMeta * meta,
2803 if (meta->reference)
2804 gst_caps_unref (meta->reference);
2808 _gst_reference_timestamp_meta_init (GstReferenceTimestampMeta * meta,
2809 gpointer params, GstBuffer * buffer)
2811 static volatile gsize _init;
2813 if (g_once_init_enter (&_init)) {
2814 GST_DEBUG_CATEGORY_INIT (gst_reference_timestamp_meta_debug,
2815 "referencetimestampmeta", 0, "referencetimestampmeta");
2816 g_once_init_leave (&_init, 1);
2819 meta->reference = NULL;
2820 meta->timestamp = GST_CLOCK_TIME_NONE;
2821 meta->duration = GST_CLOCK_TIME_NONE;
2827 * gst_reference_timestamp_meta_api_get_type: (attributes doc.skip=true)
2830 gst_reference_timestamp_meta_api_get_type (void)
2832 static volatile GType type = 0;
2833 static const gchar *tags[] = { NULL };
2835 if (g_once_init_enter (&type)) {
2837 gst_meta_api_type_register ("GstReferenceTimestampMetaAPI", tags);
2838 g_once_init_leave (&type, _type);
2845 * gst_reference_timestamp_meta_get_info:
2847 * Get the global #GstMetaInfo describing the #GstReferenceTimestampMeta meta.
2849 * Returns: (transfer none): The #GstMetaInfo
2854 gst_reference_timestamp_meta_get_info (void)
2856 static const GstMetaInfo *meta_info = NULL;
2858 if (g_once_init_enter ((GstMetaInfo **) & meta_info)) {
2859 const GstMetaInfo *meta =
2860 gst_meta_register (gst_reference_timestamp_meta_api_get_type (),
2861 "GstReferenceTimestampMeta",
2862 sizeof (GstReferenceTimestampMeta),
2863 (GstMetaInitFunction) _gst_reference_timestamp_meta_init,
2864 (GstMetaFreeFunction) _gst_reference_timestamp_meta_free,
2865 _gst_reference_timestamp_meta_transform);
2866 g_once_init_leave ((GstMetaInfo **) & meta_info, (GstMetaInfo *) meta);