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 typedef struct _GstMetaItem GstMetaItem;
144 /* info->size will be sizeof(FooMeta) which contains a GstMeta at the beginning
145 * too, and then there is again a GstMeta in GstMetaItem, so subtract one. */
146 #define ITEM_SIZE(info) ((info)->size + sizeof (GstMetaItem) - sizeof (GstMeta))
148 #define GST_BUFFER_MEM_MAX 16
150 #define GST_BUFFER_SLICE_SIZE(b) (((GstBufferImpl *)(b))->slice_size)
151 #define GST_BUFFER_MEM_LEN(b) (((GstBufferImpl *)(b))->len)
152 #define GST_BUFFER_MEM_ARRAY(b) (((GstBufferImpl *)(b))->mem)
153 #define GST_BUFFER_MEM_PTR(b,i) (((GstBufferImpl *)(b))->mem[i])
154 #define GST_BUFFER_BUFMEM(b) (((GstBufferImpl *)(b))->bufmem)
155 #define GST_BUFFER_META(b) (((GstBufferImpl *)(b))->item)
163 /* the memory blocks */
165 GstMemory *mem[GST_BUFFER_MEM_MAX];
167 /* memory of the buffer when allocated from 1 chunk */
170 /* FIXME, make metadata allocation more efficient by using part of the
177 _is_span (GstMemory ** mem, gsize len, gsize * poffset, GstMemory ** parent)
179 GstMemory *mcur, *mprv;
180 gboolean have_offset = FALSE;
185 for (i = 0; i < len; i++) {
193 /* check if memory is contiguous */
194 if (!gst_memory_is_span (mprv, mcur, &poffs))
201 *parent = mprv->parent;
211 _get_merged_memory (GstBuffer * buffer, guint idx, guint length)
213 GstMemory **mem, *result = NULL;
215 GST_CAT_LOG (GST_CAT_BUFFER, "buffer %p, idx %u, length %u", buffer, idx,
218 mem = GST_BUFFER_MEM_ARRAY (buffer);
220 if (G_UNLIKELY (length == 0)) {
222 } else if (G_LIKELY (length == 1)) {
223 result = gst_memory_ref (mem[idx]);
225 GstMemory *parent = NULL;
226 gsize size, poffset = 0;
228 size = gst_buffer_get_sizes_range (buffer, idx, length, NULL, NULL);
230 if (G_UNLIKELY (_is_span (mem + idx, length, &poffset, &parent))) {
231 if (!GST_MEMORY_IS_NO_SHARE (parent))
232 result = gst_memory_share (parent, poffset, size);
234 GST_CAT_DEBUG (GST_CAT_PERFORMANCE, "copy for merge %p", parent);
235 result = gst_memory_copy (parent, poffset, size);
238 gsize i, tocopy, left;
239 GstMapInfo sinfo, dinfo;
242 result = gst_allocator_alloc (NULL, size, NULL);
243 if (result == NULL || !gst_memory_map (result, &dinfo, GST_MAP_WRITE)) {
244 GST_CAT_ERROR (GST_CAT_BUFFER, "Failed to map memory writable");
246 gst_memory_unref (result);
253 for (i = idx; i < (idx + length) && left > 0; i++) {
254 if (!gst_memory_map (mem[i], &sinfo, GST_MAP_READ)) {
255 GST_CAT_ERROR (GST_CAT_BUFFER,
256 "buffer %p, idx %u, length %u failed to map readable", buffer,
258 gst_memory_unmap (result, &dinfo);
259 gst_memory_unref (result);
262 tocopy = MIN (sinfo.size, left);
263 GST_CAT_DEBUG (GST_CAT_PERFORMANCE,
264 "memcpy %" G_GSIZE_FORMAT " bytes for merge %p from memory %p",
265 tocopy, result, mem[i]);
266 memcpy (ptr, (guint8 *) sinfo.data, tocopy);
269 gst_memory_unmap (mem[i], &sinfo);
271 gst_memory_unmap (result, &dinfo);
278 _replace_memory (GstBuffer * buffer, guint len, guint idx, guint length,
285 GST_CAT_LOG (GST_CAT_BUFFER,
286 "buffer %p replace %u-%" G_GSIZE_FORMAT " with memory %p", buffer, idx,
289 /* unref old memory */
290 for (i = idx; i < end; i++) {
291 GstMemory *old = GST_BUFFER_MEM_PTR (buffer, i);
293 gst_memory_unlock (old, GST_LOCK_FLAG_EXCLUSIVE);
294 gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (old),
295 GST_MINI_OBJECT_CAST (buffer));
296 gst_memory_unref (old);
300 /* replace with single memory */
301 gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (mem),
302 GST_MINI_OBJECT_CAST (buffer));
303 gst_memory_lock (mem, GST_LOCK_FLAG_EXCLUSIVE);
304 GST_BUFFER_MEM_PTR (buffer, idx) = mem;
310 memmove (&GST_BUFFER_MEM_PTR (buffer, idx),
311 &GST_BUFFER_MEM_PTR (buffer, end), (len - end) * sizeof (gpointer));
313 GST_BUFFER_MEM_LEN (buffer) = len - length;
314 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
318 * gst_buffer_get_flags:
319 * @buffer: a #GstBuffer
321 * Get the #GstBufferFlags flags set on this buffer.
323 * Returns: the flags set on this buffer.
328 gst_buffer_get_flags (GstBuffer * buffer)
330 return (GstBufferFlags) GST_BUFFER_FLAGS (buffer);
334 * gst_buffer_flag_is_set:
335 * @buffer: a #GstBuffer
336 * @flags: the #GstBufferFlags flag to check.
338 * Gives the status of a specific flag on a buffer.
340 * Returns: %TRUE if all flags in @flags are found on @buffer.
345 gst_buffer_has_flags (GstBuffer * buffer, GstBufferFlags flags)
347 return GST_BUFFER_FLAG_IS_SET (buffer, flags);
351 * gst_buffer_set_flags:
352 * @buffer: a #GstBuffer
353 * @flags: the #GstBufferFlags to set.
355 * Sets one or more buffer flags on a buffer.
357 * Returns: %TRUE if @flags were successfully set on buffer.
362 gst_buffer_set_flags (GstBuffer * buffer, GstBufferFlags flags)
364 GST_BUFFER_FLAG_SET (buffer, flags);
369 * gst_buffer_unset_flags:
370 * @buffer: a #GstBuffer
371 * @flags: the #GstBufferFlags to clear
373 * Clears one or more buffer flags.
375 * Returns: true if @flags is successfully cleared from buffer.
380 gst_buffer_unset_flags (GstBuffer * buffer, GstBufferFlags flags)
382 GST_BUFFER_FLAG_UNSET (buffer, flags);
388 /* transfer full for return and transfer none for @mem */
389 static inline GstMemory *
390 _memory_get_exclusive_reference (GstMemory * mem)
392 GstMemory *ret = NULL;
394 if (gst_memory_lock (mem, GST_LOCK_FLAG_EXCLUSIVE)) {
395 ret = gst_memory_ref (mem);
397 /* we cannot take another exclusive lock as the memory is already
398 * locked WRITE + EXCLUSIVE according to part-miniobject.txt */
399 ret = gst_memory_copy (mem, 0, -1);
402 if (!gst_memory_lock (ret, GST_LOCK_FLAG_EXCLUSIVE)) {
403 gst_memory_unref (ret);
410 GST_CAT_WARNING (GST_CAT_BUFFER, "Failed to acquire an exclusive lock for "
417 _memory_add (GstBuffer * buffer, gint idx, GstMemory * mem)
419 guint i, len = GST_BUFFER_MEM_LEN (buffer);
421 GST_CAT_LOG (GST_CAT_BUFFER, "buffer %p, idx %d, mem %p", buffer, idx, mem);
423 if (G_UNLIKELY (len >= GST_BUFFER_MEM_MAX)) {
424 /* too many buffer, span them. */
425 /* FIXME, there is room for improvement here: We could only try to merge
426 * 2 buffers to make some room. If we can't efficiently merge 2 buffers we
427 * could try to only merge the two smallest buffers to avoid memcpy, etc. */
428 GST_CAT_DEBUG (GST_CAT_PERFORMANCE, "memory array overflow in buffer %p",
430 _replace_memory (buffer, len, 0, len, _get_merged_memory (buffer, 0, len));
431 /* we now have 1 single spanned buffer */
438 for (i = len; i > idx; i--) {
439 /* move buffers to insert, FIXME, we need to insert first and then merge */
440 GST_BUFFER_MEM_PTR (buffer, i) = GST_BUFFER_MEM_PTR (buffer, i - 1);
442 /* and insert the new buffer */
443 GST_BUFFER_MEM_PTR (buffer, idx) = mem;
444 GST_BUFFER_MEM_LEN (buffer) = len + 1;
445 gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (mem),
446 GST_MINI_OBJECT_CAST (buffer));
448 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
451 GST_DEFINE_MINI_OBJECT_TYPE (GstBuffer, gst_buffer);
454 _priv_gst_buffer_initialize (void)
456 _gst_buffer_type = gst_buffer_get_type ();
460 * gst_buffer_get_max_memory:
462 * Get the maximum amount of memory blocks that a buffer can hold. This is a
463 * compile time constant that can be queried with the function.
465 * When more memory blocks are added, existing memory blocks will be merged
466 * together to make room for the new block.
468 * Returns: the maximum amount of memory blocks that a buffer can hold.
473 gst_buffer_get_max_memory (void)
475 return GST_BUFFER_MEM_MAX;
479 * gst_buffer_copy_into:
480 * @dest: a destination #GstBuffer
481 * @src: a source #GstBuffer
482 * @flags: flags indicating what metadata fields should be copied.
483 * @offset: offset to copy from
484 * @size: total size to copy. If -1, all data is copied.
486 * Copies the information from @src into @dest.
488 * If @dest already contains memory and @flags contains GST_BUFFER_COPY_MEMORY,
489 * the memory from @src will be appended to @dest.
491 * @flags indicate which fields will be copied.
493 * Returns: %TRUE if the copying succeeded, %FALSE otherwise.
496 gst_buffer_copy_into (GstBuffer * dest, GstBuffer * src,
497 GstBufferCopyFlags flags, gsize offset, gsize size)
501 gboolean region = FALSE;
503 g_return_val_if_fail (dest != NULL, FALSE);
504 g_return_val_if_fail (src != NULL, FALSE);
506 /* nothing to copy if the buffers are the same */
507 if (G_UNLIKELY (dest == src))
510 g_return_val_if_fail (gst_buffer_is_writable (dest), FALSE);
512 bufsize = gst_buffer_get_size (src);
513 g_return_val_if_fail (bufsize >= offset, FALSE);
517 size = bufsize - offset;
520 g_return_val_if_fail (bufsize >= offset + size, FALSE);
522 GST_CAT_LOG (GST_CAT_BUFFER, "copy %p to %p, offset %" G_GSIZE_FORMAT
523 "-%" G_GSIZE_FORMAT "/%" G_GSIZE_FORMAT, src, dest, offset, size,
526 if (flags & GST_BUFFER_COPY_FLAGS) {
528 guint flags_mask = ~GST_BUFFER_FLAG_TAG_MEMORY;
530 GST_MINI_OBJECT_FLAGS (dest) =
531 (GST_MINI_OBJECT_FLAGS (src) & flags_mask) |
532 (GST_MINI_OBJECT_FLAGS (dest) & ~flags_mask);
535 if (flags & GST_BUFFER_COPY_TIMESTAMPS) {
537 GST_BUFFER_PTS (dest) = GST_BUFFER_PTS (src);
538 GST_BUFFER_DTS (dest) = GST_BUFFER_DTS (src);
539 GST_BUFFER_OFFSET (dest) = GST_BUFFER_OFFSET (src);
540 if (size == bufsize) {
541 GST_BUFFER_DURATION (dest) = GST_BUFFER_DURATION (src);
542 GST_BUFFER_OFFSET_END (dest) = GST_BUFFER_OFFSET_END (src);
545 GST_BUFFER_PTS (dest) = GST_CLOCK_TIME_NONE;
546 GST_BUFFER_DTS (dest) = GST_CLOCK_TIME_NONE;
547 GST_BUFFER_DURATION (dest) = GST_CLOCK_TIME_NONE;
548 GST_BUFFER_OFFSET (dest) = GST_BUFFER_OFFSET_NONE;
549 GST_BUFFER_OFFSET_END (dest) = GST_BUFFER_OFFSET_NONE;
553 if (flags & GST_BUFFER_COPY_MEMORY) {
554 gsize skip, left, len, dest_len, i, bsize;
557 deep = flags & GST_BUFFER_COPY_DEEP;
559 len = GST_BUFFER_MEM_LEN (src);
560 dest_len = GST_BUFFER_MEM_LEN (dest);
564 /* copy and make regions of the memory */
565 for (i = 0; i < len && left > 0; i++) {
566 GstMemory *mem = GST_BUFFER_MEM_PTR (src, i);
568 bsize = gst_memory_get_sizes (mem, NULL, NULL);
571 /* don't copy buffer */
574 GstMemory *newmem = NULL;
577 tocopy = MIN (bsize - skip, left);
579 if (tocopy < bsize && !deep && !GST_MEMORY_IS_NO_SHARE (mem)) {
580 /* we need to clip something */
581 newmem = gst_memory_share (mem, skip, tocopy);
583 gst_memory_lock (newmem, GST_LOCK_FLAG_EXCLUSIVE);
588 if (deep || GST_MEMORY_IS_NO_SHARE (mem) || (!newmem && tocopy < bsize)) {
589 /* deep copy or we're not allowed to share this memory
590 * between buffers, always copy then */
591 newmem = gst_memory_copy (mem, skip, tocopy);
593 gst_memory_lock (newmem, GST_LOCK_FLAG_EXCLUSIVE);
596 } else if (!newmem) {
597 newmem = _memory_get_exclusive_reference (mem);
601 gst_buffer_remove_memory_range (dest, dest_len, -1);
605 _memory_add (dest, -1, newmem);
609 if (flags & GST_BUFFER_COPY_MERGE) {
612 len = GST_BUFFER_MEM_LEN (dest);
613 mem = _get_merged_memory (dest, 0, len);
615 gst_buffer_remove_memory_range (dest, dest_len, -1);
618 _replace_memory (dest, len, 0, len, mem);
622 if (flags & GST_BUFFER_COPY_META) {
623 /* NOTE: GstGLSyncMeta copying relies on the meta
624 * being copied now, after the buffer data,
625 * so this has to happen last */
626 for (walk = GST_BUFFER_META (src); walk; walk = walk->next) {
627 GstMeta *meta = &walk->meta;
628 const GstMetaInfo *info = meta->info;
630 /* Don't copy memory metas if we only copied part of the buffer, didn't
631 * copy memories or merged memories. In all these cases the memory
632 * structure has changed and the memory meta becomes meaningless.
634 if ((region || !(flags & GST_BUFFER_COPY_MEMORY)
635 || (flags & GST_BUFFER_COPY_MERGE))
636 && gst_meta_api_type_has_tag (info->api, _gst_meta_tag_memory)) {
637 GST_CAT_DEBUG (GST_CAT_BUFFER,
638 "don't copy memory meta %p of API type %s", meta,
639 g_type_name (info->api));
640 } else if (info->transform_func) {
641 GstMetaTransformCopy copy_data;
643 copy_data.region = region;
644 copy_data.offset = offset;
645 copy_data.size = size;
647 if (!info->transform_func (dest, meta, src,
648 _gst_meta_transform_copy, ©_data)) {
649 GST_CAT_ERROR (GST_CAT_BUFFER,
650 "failed to copy meta %p of API type %s", meta,
651 g_type_name (info->api));
661 gst_buffer_copy_with_flags (const GstBuffer * buffer, GstBufferCopyFlags flags)
665 g_return_val_if_fail (buffer != NULL, NULL);
667 /* create a fresh new buffer */
668 copy = gst_buffer_new ();
670 /* copy what the 'flags' want from our parent */
671 /* FIXME why we can't pass const to gst_buffer_copy_into() ? */
672 if (!gst_buffer_copy_into (copy, (GstBuffer *) buffer, flags, 0, -1))
673 gst_buffer_replace (©, NULL);
676 GST_BUFFER_FLAG_UNSET (copy, GST_BUFFER_FLAG_TAG_MEMORY);
682 _gst_buffer_copy (const GstBuffer * buffer)
684 return gst_buffer_copy_with_flags (buffer, GST_BUFFER_COPY_ALL);
688 * gst_buffer_copy_deep:
689 * @buf: a #GstBuffer.
691 * Create a copy of the given buffer. This will make a newly allocated
692 * copy of the data the source buffer contains.
694 * Returns: (transfer full): a new copy of @buf.
699 gst_buffer_copy_deep (const GstBuffer * buffer)
701 return gst_buffer_copy_with_flags (buffer,
702 GST_BUFFER_COPY_ALL | GST_BUFFER_COPY_DEEP);
705 /* the default dispose function revives the buffer and returns it to the
706 * pool when there is a pool */
708 _gst_buffer_dispose (GstBuffer * buffer)
712 /* no pool, do free */
713 if ((pool = buffer->pool) == NULL)
716 /* keep the buffer alive */
717 gst_buffer_ref (buffer);
718 /* return the buffer to the pool */
719 GST_CAT_LOG (GST_CAT_BUFFER, "release %p to pool %p", buffer, pool);
720 gst_buffer_pool_release_buffer (pool, buffer);
726 _gst_buffer_free (GstBuffer * buffer)
728 GstMetaItem *walk, *next;
732 g_return_if_fail (buffer != NULL);
734 GST_CAT_LOG (GST_CAT_BUFFER, "finalize %p", buffer);
737 for (walk = GST_BUFFER_META (buffer); walk; walk = next) {
738 GstMeta *meta = &walk->meta;
739 const GstMetaInfo *info = meta->info;
741 /* call free_func if any */
743 info->free_func (meta, buffer);
746 /* and free the slice */
747 g_slice_free1 (ITEM_SIZE (info), walk);
750 /* get the size, when unreffing the memory, we could also unref the buffer
752 msize = GST_BUFFER_SLICE_SIZE (buffer);
754 /* free our memory */
755 len = GST_BUFFER_MEM_LEN (buffer);
756 for (i = 0; i < len; i++) {
757 gst_memory_unlock (GST_BUFFER_MEM_PTR (buffer, i), GST_LOCK_FLAG_EXCLUSIVE);
758 gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (GST_BUFFER_MEM_PTR
759 (buffer, i)), GST_MINI_OBJECT_CAST (buffer));
760 gst_memory_unref (GST_BUFFER_MEM_PTR (buffer, i));
763 /* we set msize to 0 when the buffer is part of the memory block */
766 memset (buffer, 0xff, msize);
768 g_slice_free1 (msize, buffer);
770 gst_memory_unref (GST_BUFFER_BUFMEM (buffer));
775 gst_buffer_init (GstBufferImpl * buffer, gsize size)
777 gst_mini_object_init (GST_MINI_OBJECT_CAST (buffer), 0, _gst_buffer_type,
778 (GstMiniObjectCopyFunction) _gst_buffer_copy,
779 (GstMiniObjectDisposeFunction) _gst_buffer_dispose,
780 (GstMiniObjectFreeFunction) _gst_buffer_free);
782 GST_BUFFER_SLICE_SIZE (buffer) = size;
784 GST_BUFFER (buffer)->pool = NULL;
785 GST_BUFFER_PTS (buffer) = GST_CLOCK_TIME_NONE;
786 GST_BUFFER_DTS (buffer) = GST_CLOCK_TIME_NONE;
787 GST_BUFFER_DURATION (buffer) = GST_CLOCK_TIME_NONE;
788 GST_BUFFER_OFFSET (buffer) = GST_BUFFER_OFFSET_NONE;
789 GST_BUFFER_OFFSET_END (buffer) = GST_BUFFER_OFFSET_NONE;
791 GST_BUFFER_MEM_LEN (buffer) = 0;
792 GST_BUFFER_META (buffer) = NULL;
798 * Creates a newly allocated buffer without any data.
802 * Returns: (transfer full): the new #GstBuffer.
805 gst_buffer_new (void)
807 GstBufferImpl *newbuf;
809 newbuf = g_slice_new (GstBufferImpl);
810 GST_CAT_LOG (GST_CAT_BUFFER, "new %p", newbuf);
812 gst_buffer_init (newbuf, sizeof (GstBufferImpl));
814 return GST_BUFFER_CAST (newbuf);
818 * gst_buffer_new_allocate:
819 * @allocator: (transfer none) (allow-none): the #GstAllocator to use, or %NULL to use the
821 * @size: the size in bytes of the new buffer's data.
822 * @params: (transfer none) (allow-none): optional parameters
824 * Tries to create a newly allocated buffer with data of the given size and
825 * extra parameters from @allocator. If the requested amount of memory can't be
826 * allocated, %NULL will be returned. The allocated buffer memory is not cleared.
828 * When @allocator is %NULL, the default memory allocator will be used.
830 * Note that when @size == 0, the buffer will not have memory associated with it.
834 * Returns: (transfer full) (nullable): a new #GstBuffer, or %NULL if
835 * the memory couldn't be allocated.
838 gst_buffer_new_allocate (GstAllocator * allocator, gsize size,
839 GstAllocationParams * params)
850 mem = gst_allocator_alloc (allocator, size, params);
851 if (G_UNLIKELY (mem == NULL))
857 newbuf = gst_buffer_new ();
860 gst_memory_lock (mem, GST_LOCK_FLAG_EXCLUSIVE);
861 _memory_add (newbuf, -1, mem);
864 GST_CAT_LOG (GST_CAT_BUFFER,
865 "new buffer %p of size %" G_GSIZE_FORMAT " from allocator %p", newbuf,
870 asize = sizeof (GstBufferImpl) + size;
871 data = g_slice_alloc (asize);
872 if (G_UNLIKELY (data == NULL))
875 newbuf = GST_BUFFER_CAST (data);
877 gst_buffer_init ((GstBufferImpl *) data, asize);
879 mem = gst_memory_new_wrapped (0, data + sizeof (GstBufferImpl), NULL,
881 _memory_add (newbuf, -1, mem, TRUE);
886 /* allocate memory and buffer, it might be interesting to do this but there
887 * are many complications. We need to keep the memory mapped to access the
888 * buffer fields and the memory for the buffer might be just very slow. We
889 * also need to do some more magic to get the alignment right. */
890 asize = sizeof (GstBufferImpl) + size;
891 mem = gst_allocator_alloc (allocator, asize, align);
892 if (G_UNLIKELY (mem == NULL))
895 /* map the data part and init the buffer in it, set the buffer size to 0 so
896 * that a finalize won't free the buffer */
897 data = gst_memory_map (mem, &asize, NULL, GST_MAP_WRITE);
898 gst_buffer_init ((GstBufferImpl *) data, 0);
899 gst_memory_unmap (mem);
901 /* strip off the buffer */
902 gst_memory_resize (mem, sizeof (GstBufferImpl), size);
904 newbuf = GST_BUFFER_CAST (data);
905 GST_BUFFER_BUFMEM (newbuf) = mem;
908 _memory_add (newbuf, -1, gst_memory_ref (mem), TRUE);
910 GST_BUFFER_FLAG_UNSET (newbuf, GST_BUFFER_FLAG_TAG_MEMORY);
917 GST_CAT_WARNING (GST_CAT_BUFFER,
918 "failed to allocate %" G_GSIZE_FORMAT " bytes", size);
924 * gst_buffer_new_wrapped_full:
925 * @flags: #GstMemoryFlags
926 * @data: (array length=size) (element-type guint8) (transfer none): data to wrap
927 * @maxsize: allocated size of @data
928 * @offset: offset in @data
929 * @size: size of valid data
930 * @user_data: (allow-none): user_data
931 * @notify: (allow-none) (scope async) (closure user_data): called with @user_data when the memory is freed
933 * Allocate a new buffer that wraps the given memory. @data must point to
934 * @maxsize of memory, the wrapped buffer will have the region from @offset and
937 * When the buffer is destroyed, @notify will be called with @user_data.
939 * The prefix/padding must be filled with 0 if @flags contains
940 * #GST_MEMORY_FLAG_ZERO_PREFIXED and #GST_MEMORY_FLAG_ZERO_PADDED respectively.
942 * Returns: (transfer full): a new #GstBuffer
945 gst_buffer_new_wrapped_full (GstMemoryFlags flags, gpointer data,
946 gsize maxsize, gsize offset, gsize size, gpointer user_data,
947 GDestroyNotify notify)
952 newbuf = gst_buffer_new ();
954 gst_memory_new_wrapped (flags, data, maxsize, offset, size, user_data,
956 gst_memory_lock (mem, GST_LOCK_FLAG_EXCLUSIVE);
957 _memory_add (newbuf, -1, mem);
958 GST_BUFFER_FLAG_UNSET (newbuf, GST_BUFFER_FLAG_TAG_MEMORY);
964 * gst_buffer_new_wrapped:
965 * @data: (array length=size) (element-type guint8) (transfer full): data to wrap
966 * @size: allocated size of @data
968 * Creates a new buffer that wraps the given @data. The memory will be freed
969 * with g_free and will be marked writable.
973 * Returns: (transfer full): a new #GstBuffer
976 gst_buffer_new_wrapped (gpointer data, gsize size)
978 return gst_buffer_new_wrapped_full (0, data, size, 0, size, data, g_free);
982 * gst_buffer_new_wrapped_bytes:
983 * @bytes: (transfer none): a #GBytes to wrap
985 * Creates a new #GstBuffer that wraps the given @bytes. The data inside
986 * @bytes cannot be %NULL and the resulting buffer will be marked as read only.
990 * Returns: (transfer full): a new #GstBuffer wrapping @bytes
995 gst_buffer_new_wrapped_bytes (GBytes * bytes)
1000 g_return_val_if_fail (bytes != NULL, NULL);
1001 bytes_data = (guint8 *) g_bytes_get_data (bytes, &size);
1002 g_return_val_if_fail (bytes_data != NULL, NULL);
1004 return gst_buffer_new_wrapped_full (GST_MEMORY_FLAG_READONLY, bytes_data,
1005 size, 0, size, g_bytes_ref (bytes), (GDestroyNotify) g_bytes_unref);
1009 * gst_buffer_n_memory:
1010 * @buffer: a #GstBuffer.
1012 * Get the amount of memory blocks that this buffer has. This amount is never
1013 * larger than what gst_buffer_get_max_memory() returns.
1015 * Returns: the number of memory blocks this buffer is made of.
1018 gst_buffer_n_memory (GstBuffer * buffer)
1020 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1022 return GST_BUFFER_MEM_LEN (buffer);
1026 * gst_buffer_prepend_memory:
1027 * @buffer: a #GstBuffer.
1028 * @mem: (transfer full): a #GstMemory.
1030 * Prepend the memory block @mem to @buffer. This function takes
1031 * ownership of @mem and thus doesn't increase its refcount.
1033 * This function is identical to gst_buffer_insert_memory() with an index of 0.
1034 * See gst_buffer_insert_memory() for more details.
1037 gst_buffer_prepend_memory (GstBuffer * buffer, GstMemory * mem)
1039 gst_buffer_insert_memory (buffer, 0, mem);
1043 * gst_buffer_append_memory:
1044 * @buffer: a #GstBuffer.
1045 * @mem: (transfer full): a #GstMemory.
1047 * Append the memory block @mem to @buffer. This function takes
1048 * ownership of @mem and thus doesn't increase its refcount.
1050 * This function is identical to gst_buffer_insert_memory() with an index of -1.
1051 * See gst_buffer_insert_memory() for more details.
1054 gst_buffer_append_memory (GstBuffer * buffer, GstMemory * mem)
1056 gst_buffer_insert_memory (buffer, -1, mem);
1060 * gst_buffer_insert_memory:
1061 * @buffer: a #GstBuffer.
1062 * @idx: the index to add the memory at, or -1 to append it to the end
1063 * @mem: (transfer full): a #GstMemory.
1065 * Insert the memory block @mem to @buffer at @idx. This function takes ownership
1066 * of @mem and thus doesn't increase its refcount.
1068 * Only gst_buffer_get_max_memory() can be added to a buffer. If more memory is
1069 * added, existing memory blocks will automatically be merged to make room for
1073 gst_buffer_insert_memory (GstBuffer * buffer, gint idx, GstMemory * mem)
1077 g_return_if_fail (GST_IS_BUFFER (buffer));
1078 g_return_if_fail (gst_buffer_is_writable (buffer));
1079 g_return_if_fail (mem != NULL);
1080 g_return_if_fail (idx == -1 ||
1081 (idx >= 0 && idx <= GST_BUFFER_MEM_LEN (buffer)));
1083 tmp = _memory_get_exclusive_reference (mem);
1084 g_return_if_fail (tmp != NULL);
1085 gst_memory_unref (mem);
1086 _memory_add (buffer, idx, tmp);
1090 _get_mapped (GstBuffer * buffer, guint idx, GstMapInfo * info,
1093 GstMemory *mem, *mapped;
1095 mem = gst_memory_ref (GST_BUFFER_MEM_PTR (buffer, idx));
1097 mapped = gst_memory_make_mapped (mem, info, flags);
1099 if (mapped != mem) {
1100 /* memory changed, lock new memory */
1101 gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (mapped),
1102 GST_MINI_OBJECT_CAST (buffer));
1103 gst_memory_lock (mapped, GST_LOCK_FLAG_EXCLUSIVE);
1104 GST_BUFFER_MEM_PTR (buffer, idx) = mapped;
1105 /* unlock old memory */
1106 gst_memory_unlock (mem, GST_LOCK_FLAG_EXCLUSIVE);
1107 gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (mem),
1108 GST_MINI_OBJECT_CAST (buffer));
1109 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
1111 gst_memory_unref (mem);
1117 * gst_buffer_peek_memory:
1118 * @buffer: a #GstBuffer.
1121 * Get the memory block at @idx in @buffer. The memory block stays valid until
1122 * the memory block in @buffer is removed, replaced or merged, typically with
1123 * any call that modifies the memory in @buffer.
1125 * Returns: (transfer none) (nullable): the #GstMemory at @idx.
1128 gst_buffer_peek_memory (GstBuffer * buffer, guint idx)
1132 g_return_val_if_fail (GST_IS_BUFFER (buffer), NULL);
1133 len = GST_BUFFER_MEM_LEN (buffer);
1134 g_return_val_if_fail (idx < len, NULL);
1136 return GST_BUFFER_MEM_PTR (buffer, idx);
1140 * gst_buffer_get_memory:
1141 * @buffer: a #GstBuffer.
1144 * Get the memory block at index @idx in @buffer.
1146 * Returns: (transfer full) (nullable): a #GstMemory that contains the data of the
1147 * memory block at @idx. Use gst_memory_unref () after usage.
1150 gst_buffer_get_memory (GstBuffer * buffer, guint idx)
1152 return gst_buffer_get_memory_range (buffer, idx, 1);
1156 * gst_buffer_get_all_memory:
1157 * @buffer: a #GstBuffer.
1159 * Get all the memory block in @buffer. The memory blocks will be merged
1160 * into one large #GstMemory.
1162 * Returns: (transfer full) (nullable): a #GstMemory that contains the merged memory.
1163 * Use gst_memory_unref () after usage.
1166 gst_buffer_get_all_memory (GstBuffer * buffer)
1168 return gst_buffer_get_memory_range (buffer, 0, -1);
1172 * gst_buffer_get_memory_range:
1173 * @buffer: a #GstBuffer.
1177 * Get @length memory blocks in @buffer starting at @idx. The memory blocks will
1178 * be merged into one large #GstMemory.
1180 * If @length is -1, all memory starting from @idx is merged.
1182 * Returns: (transfer full) (nullable): a #GstMemory that contains the merged data of @length
1183 * blocks starting at @idx. Use gst_memory_unref () after usage.
1186 gst_buffer_get_memory_range (GstBuffer * buffer, guint idx, gint length)
1190 GST_CAT_DEBUG (GST_CAT_BUFFER, "idx %u, length %d", idx, length);
1192 g_return_val_if_fail (GST_IS_BUFFER (buffer), NULL);
1193 len = GST_BUFFER_MEM_LEN (buffer);
1194 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1195 (length == -1 && idx < len) || (length > 0 && length + idx <= len), NULL);
1200 return _get_merged_memory (buffer, idx, length);
1204 * gst_buffer_replace_memory:
1205 * @buffer: a #GstBuffer.
1207 * @mem: (transfer full): a #GstMemory
1209 * Replaces the memory block at index @idx in @buffer with @mem.
1212 gst_buffer_replace_memory (GstBuffer * buffer, guint idx, GstMemory * mem)
1214 gst_buffer_replace_memory_range (buffer, idx, 1, mem);
1218 * gst_buffer_replace_all_memory:
1219 * @buffer: a #GstBuffer.
1220 * @mem: (transfer full): a #GstMemory
1222 * Replaces all memory in @buffer with @mem.
1225 gst_buffer_replace_all_memory (GstBuffer * buffer, GstMemory * mem)
1227 gst_buffer_replace_memory_range (buffer, 0, -1, mem);
1231 * gst_buffer_replace_memory_range:
1232 * @buffer: a #GstBuffer.
1234 * @length: a length should not be 0
1235 * @mem: (transfer full): a #GstMemory
1237 * Replaces @length memory blocks in @buffer starting at @idx with @mem.
1239 * If @length is -1, all memory starting from @idx will be removed and
1240 * replaced with @mem.
1242 * @buffer should be writable.
1245 gst_buffer_replace_memory_range (GstBuffer * buffer, guint idx, gint length,
1250 g_return_if_fail (GST_IS_BUFFER (buffer));
1251 g_return_if_fail (gst_buffer_is_writable (buffer));
1253 GST_CAT_DEBUG (GST_CAT_BUFFER, "idx %u, length %d, %p", idx, length, mem);
1255 len = GST_BUFFER_MEM_LEN (buffer);
1256 g_return_if_fail ((len == 0 && idx == 0 && length == -1) ||
1257 (length == -1 && idx < len) || (length > 0 && length + idx <= len));
1262 _replace_memory (buffer, len, idx, length, mem);
1266 * gst_buffer_remove_memory:
1267 * @buffer: a #GstBuffer.
1270 * Remove the memory block in @b at index @i.
1273 gst_buffer_remove_memory (GstBuffer * buffer, guint idx)
1275 gst_buffer_remove_memory_range (buffer, idx, 1);
1279 * gst_buffer_remove_all_memory:
1280 * @buffer: a #GstBuffer.
1282 * Remove all the memory blocks in @buffer.
1285 gst_buffer_remove_all_memory (GstBuffer * buffer)
1287 gst_buffer_remove_memory_range (buffer, 0, -1);
1291 * gst_buffer_remove_memory_range:
1292 * @buffer: a #GstBuffer.
1296 * Remove @length memory blocks in @buffer starting from @idx.
1298 * @length can be -1, in which case all memory starting from @idx is removed.
1301 gst_buffer_remove_memory_range (GstBuffer * buffer, guint idx, gint length)
1305 g_return_if_fail (GST_IS_BUFFER (buffer));
1306 g_return_if_fail (gst_buffer_is_writable (buffer));
1308 GST_CAT_DEBUG (GST_CAT_BUFFER, "idx %u, length %d", idx, length);
1310 len = GST_BUFFER_MEM_LEN (buffer);
1311 g_return_if_fail ((len == 0 && idx == 0 && length == -1) ||
1312 (length == -1 && idx < len) || length + idx <= len);
1317 _replace_memory (buffer, len, idx, length, NULL);
1321 * gst_buffer_find_memory:
1322 * @buffer: a #GstBuffer.
1323 * @offset: an offset
1325 * @idx: (out): pointer to index
1326 * @length: (out): pointer to length
1327 * @skip: (out): pointer to skip
1329 * Find the memory blocks that span @size bytes starting from @offset
1332 * When this function returns %TRUE, @idx will contain the index of the first
1333 * memory block where the byte for @offset can be found and @length contains the
1334 * number of memory blocks containing the @size remaining bytes. @skip contains
1335 * the number of bytes to skip in the memory block at @idx to get to the byte
1338 * @size can be -1 to get all the memory blocks after @idx.
1340 * Returns: %TRUE when @size bytes starting from @offset could be found in
1341 * @buffer and @idx, @length and @skip will be filled.
1344 gst_buffer_find_memory (GstBuffer * buffer, gsize offset, gsize size,
1345 guint * idx, guint * length, gsize * skip)
1347 guint i, len, found;
1349 g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
1350 g_return_val_if_fail (idx != NULL, FALSE);
1351 g_return_val_if_fail (length != NULL, FALSE);
1352 g_return_val_if_fail (skip != NULL, FALSE);
1354 len = GST_BUFFER_MEM_LEN (buffer);
1357 for (i = 0; i < len; i++) {
1361 mem = GST_BUFFER_MEM_PTR (buffer, i);
1362 s = gst_memory_get_sizes (mem, NULL, NULL);
1365 /* block before offset, or empty block, skip */
1368 /* block after offset */
1370 /* first block, remember index and offset */
1374 /* return remaining blocks */
1381 /* count the amount of found bytes */
1383 if (found >= size) {
1384 /* we have enough bytes */
1385 *length = i - *idx + 1;
1394 * gst_buffer_is_memory_range_writable:
1395 * @buffer: a #GstBuffer.
1397 * @length: a length should not be 0
1399 * Check if @length memory blocks in @buffer starting from @idx are writable.
1401 * @length can be -1 to check all the memory blocks after @idx.
1403 * Note that this function does not check if @buffer is writable, use
1404 * gst_buffer_is_writable() to check that if needed.
1406 * Returns: %TRUE if the memory range is writable
1411 gst_buffer_is_memory_range_writable (GstBuffer * buffer, guint idx, gint length)
1415 g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
1417 GST_CAT_DEBUG (GST_CAT_BUFFER, "idx %u, length %d", idx, length);
1419 len = GST_BUFFER_MEM_LEN (buffer);
1420 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1421 (length == -1 && idx < len) || (length > 0 && length + idx <= len),
1429 for (i = 0; i < len; i++) {
1430 if (!gst_memory_is_writable (GST_BUFFER_MEM_PTR (buffer, i + idx)))
1437 * gst_buffer_is_all_memory_writable:
1438 * @buffer: a #GstBuffer.
1440 * Check if all memory blocks in @buffer are writable.
1442 * Note that this function does not check if @buffer is writable, use
1443 * gst_buffer_is_writable() to check that if needed.
1445 * Returns: %TRUE if all memory blocks in @buffer are writable
1450 gst_buffer_is_all_memory_writable (GstBuffer * buffer)
1452 return gst_buffer_is_memory_range_writable (buffer, 0, -1);
1456 * gst_buffer_get_sizes:
1457 * @buffer: a #GstBuffer.
1458 * @offset: (out) (allow-none): a pointer to the offset
1459 * @maxsize: (out) (allow-none): a pointer to the maxsize
1461 * Get the total size of the memory blocks in @b.
1463 * When not %NULL, @offset will contain the offset of the data in the
1464 * first memory block in @buffer and @maxsize will contain the sum of
1465 * the size and @offset and the amount of extra padding on the last
1466 * memory block. @offset and @maxsize can be used to resize the
1467 * buffer memory blocks with gst_buffer_resize().
1469 * Returns: total size of the memory blocks in @buffer.
1472 gst_buffer_get_sizes (GstBuffer * buffer, gsize * offset, gsize * maxsize)
1474 return gst_buffer_get_sizes_range (buffer, 0, -1, offset, maxsize);
1478 * gst_buffer_get_size:
1479 * @buffer: a #GstBuffer.
1481 * Get the total size of the memory blocks in @buffer.
1483 * Returns: total size of the memory blocks in @buffer.
1486 gst_buffer_get_size (GstBuffer * buffer)
1488 return gst_buffer_get_sizes_range (buffer, 0, -1, NULL, NULL);
1492 * gst_buffer_get_sizes_range:
1493 * @buffer: a #GstBuffer.
1496 * @offset: (out) (allow-none): a pointer to the offset
1497 * @maxsize: (out) (allow-none): a pointer to the maxsize
1499 * Get the total size of @length memory blocks stating from @idx in @buffer.
1501 * When not %NULL, @offset will contain the offset of the data in the
1502 * memory block in @buffer at @idx and @maxsize will contain the sum of the size
1503 * and @offset and the amount of extra padding on the memory block at @idx +
1505 * @offset and @maxsize can be used to resize the buffer memory blocks with
1506 * gst_buffer_resize_range().
1508 * Returns: total size of @length memory blocks starting at @idx in @buffer.
1511 gst_buffer_get_sizes_range (GstBuffer * buffer, guint idx, gint length,
1512 gsize * offset, gsize * maxsize)
1518 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1519 len = GST_BUFFER_MEM_LEN (buffer);
1520 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1521 (length == -1 && idx < len) || (length + idx <= len), 0);
1526 if (G_LIKELY (length == 1)) {
1528 mem = GST_BUFFER_MEM_PTR (buffer, idx);
1529 size = gst_memory_get_sizes (mem, offset, maxsize);
1535 size = offs = extra = 0;
1536 for (i = idx; i < end; i++) {
1539 mem = GST_BUFFER_MEM_PTR (buffer, i);
1540 s = gst_memory_get_sizes (mem, &o, &ms);
1544 /* first size, take accumulated data before as the offset */
1548 /* save the amount of data after this block */
1549 extra = ms - (o + s);
1551 /* empty block, add as extra */
1558 *maxsize = offs + size + extra;
1564 * gst_buffer_resize:
1565 * @buffer: a #GstBuffer.
1566 * @offset: the offset adjustment
1567 * @size: the new size or -1 to just adjust the offset
1569 * Set the offset and total size of the memory blocks in @buffer.
1572 gst_buffer_resize (GstBuffer * buffer, gssize offset, gssize size)
1574 gst_buffer_resize_range (buffer, 0, -1, offset, size);
1578 * gst_buffer_set_size:
1579 * @buffer: a #GstBuffer.
1580 * @size: the new size
1582 * Set the total size of the memory blocks in @buffer.
1585 gst_buffer_set_size (GstBuffer * buffer, gssize size)
1587 gst_buffer_resize_range (buffer, 0, -1, 0, size);
1591 * gst_buffer_resize_range:
1592 * @buffer: a #GstBuffer.
1595 * @offset: the offset adjustment
1596 * @size: the new size or -1 to just adjust the offset
1598 * Set the total size of the @length memory blocks starting at @idx in
1601 * Returns: %TRUE if resizing succeeded, %FALSE otherwise.
1604 gst_buffer_resize_range (GstBuffer * buffer, guint idx, gint length,
1605 gssize offset, gssize size)
1608 gsize bsize, bufsize, bufoffs, bufmax;
1610 g_return_val_if_fail (gst_buffer_is_writable (buffer), FALSE);
1611 g_return_val_if_fail (size >= -1, FALSE);
1613 len = GST_BUFFER_MEM_LEN (buffer);
1614 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1615 (length == -1 && idx < len) || (length + idx <= len), FALSE);
1620 bufsize = gst_buffer_get_sizes_range (buffer, idx, length, &bufoffs, &bufmax);
1622 GST_CAT_LOG (GST_CAT_BUFFER, "trim %p %" G_GSSIZE_FORMAT "-%" G_GSSIZE_FORMAT
1623 " size:%" G_GSIZE_FORMAT " offs:%" G_GSIZE_FORMAT " max:%"
1624 G_GSIZE_FORMAT, buffer, offset, size, bufsize, bufoffs, bufmax);
1626 /* we can't go back further than the current offset or past the end of the
1628 g_return_val_if_fail ((offset < 0 && bufoffs >= -offset) || (offset >= 0
1629 && bufoffs + offset <= bufmax), FALSE);
1631 g_return_val_if_fail (bufsize >= offset, FALSE);
1632 size = bufsize - offset;
1634 g_return_val_if_fail (bufmax >= bufoffs + offset + size, FALSE);
1637 if (offset == 0 && size == bufsize)
1642 for (i = idx; i < end; i++) {
1646 mem = GST_BUFFER_MEM_PTR (buffer, i);
1647 bsize = gst_memory_get_sizes (mem, NULL, NULL);
1650 /* last buffer always gets resized to the remaining size */
1653 /* shrink buffers before the offset */
1654 else if ((gssize) bsize <= offset) {
1656 noffs = offset - bsize;
1659 /* clip other buffers */
1661 left = MIN (bsize - offset, size);
1663 if (offset != 0 || left != bsize) {
1664 if (gst_memory_is_writable (mem)) {
1665 gst_memory_resize (mem, offset, left);
1667 GstMemory *newmem = NULL;
1669 if (!GST_MEMORY_IS_NO_SHARE (mem))
1670 newmem = gst_memory_share (mem, offset, left);
1673 newmem = gst_memory_copy (mem, offset, left);
1678 gst_mini_object_add_parent (GST_MINI_OBJECT_CAST (newmem),
1679 GST_MINI_OBJECT_CAST (buffer));
1680 gst_memory_lock (newmem, GST_LOCK_FLAG_EXCLUSIVE);
1681 GST_BUFFER_MEM_PTR (buffer, i) = newmem;
1682 gst_memory_unlock (mem, GST_LOCK_FLAG_EXCLUSIVE);
1683 gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (mem),
1684 GST_MINI_OBJECT_CAST (buffer));
1685 gst_memory_unref (mem);
1687 GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_TAG_MEMORY);
1700 * @buffer: a #GstBuffer.
1701 * @info: (out): info about the mapping
1702 * @flags: flags for the mapping
1704 * This function fills @info with the #GstMapInfo of all merged memory
1705 * blocks in @buffer.
1707 * @flags describe the desired access of the memory. When @flags is
1708 * #GST_MAP_WRITE, @buffer should be writable (as returned from
1709 * gst_buffer_is_writable()).
1711 * When @buffer is writable but the memory isn't, a writable copy will
1712 * automatically be created and returned. The readonly copy of the
1713 * buffer memory will then also be replaced with this writable copy.
1715 * The memory in @info should be unmapped with gst_buffer_unmap() after
1718 * Returns: %TRUE if the map succeeded and @info contains valid data.
1721 gst_buffer_map (GstBuffer * buffer, GstMapInfo * info, GstMapFlags flags)
1723 return gst_buffer_map_range (buffer, 0, -1, info, flags);
1727 * gst_buffer_map_range:
1728 * @buffer: a #GstBuffer.
1731 * @info: (out): info about the mapping
1732 * @flags: flags for the mapping
1734 * This function fills @info with the #GstMapInfo of @length merged memory blocks
1735 * starting at @idx in @buffer. When @length is -1, all memory blocks starting
1736 * from @idx are merged and mapped.
1738 * @flags describe the desired access of the memory. When @flags is
1739 * #GST_MAP_WRITE, @buffer should be writable (as returned from
1740 * gst_buffer_is_writable()).
1742 * When @buffer is writable but the memory isn't, a writable copy will
1743 * automatically be created and returned. The readonly copy of the buffer memory
1744 * will then also be replaced with this writable copy.
1746 * The memory in @info should be unmapped with gst_buffer_unmap() after usage.
1748 * Returns: %TRUE if the map succeeded and @info contains valid
1752 gst_buffer_map_range (GstBuffer * buffer, guint idx, gint length,
1753 GstMapInfo * info, GstMapFlags flags)
1755 GstMemory *mem, *nmem;
1756 gboolean write, writable;
1759 g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
1760 g_return_val_if_fail (info != NULL, FALSE);
1761 len = GST_BUFFER_MEM_LEN (buffer);
1762 g_return_val_if_fail ((len == 0 && idx == 0 && length == -1) ||
1763 (length == -1 && idx < len) || (length > 0
1764 && length + idx <= len), FALSE);
1766 GST_CAT_LOG (GST_CAT_BUFFER, "buffer %p, idx %u, length %d, flags %04x",
1767 buffer, idx, length, flags);
1769 write = (flags & GST_MAP_WRITE) != 0;
1770 writable = gst_buffer_is_writable (buffer);
1772 /* check if we can write when asked for write access */
1773 if (G_UNLIKELY (write && !writable))
1779 mem = _get_merged_memory (buffer, idx, length);
1780 if (G_UNLIKELY (mem == NULL))
1783 /* now try to map */
1784 nmem = gst_memory_make_mapped (mem, info, flags);
1785 if (G_UNLIKELY (nmem == NULL))
1788 /* if we merged or when the map returned a different memory, we try to replace
1789 * the memory in the buffer */
1790 if (G_UNLIKELY (length > 1 || nmem != mem)) {
1791 /* if the buffer is writable, replace the memory */
1793 _replace_memory (buffer, len, idx, length, gst_memory_ref (nmem));
1796 GST_CAT_DEBUG (GST_CAT_PERFORMANCE,
1797 "temporary mapping for memory %p in buffer %p", nmem, buffer);
1806 GST_WARNING_OBJECT (buffer, "write map requested on non-writable buffer");
1807 g_critical ("write map requested on non-writable buffer");
1808 memset (info, 0, sizeof (GstMapInfo));
1813 /* empty buffer, we need to return NULL */
1814 GST_DEBUG_OBJECT (buffer, "can't get buffer memory");
1815 memset (info, 0, sizeof (GstMapInfo));
1820 GST_DEBUG_OBJECT (buffer, "cannot map memory");
1821 memset (info, 0, sizeof (GstMapInfo));
1828 * @buffer: a #GstBuffer.
1829 * @info: a #GstMapInfo
1831 * Release the memory previously mapped with gst_buffer_map().
1834 gst_buffer_unmap (GstBuffer * buffer, GstMapInfo * info)
1836 g_return_if_fail (GST_IS_BUFFER (buffer));
1837 g_return_if_fail (info != NULL);
1839 /* we need to check for NULL, it is possible that we tried to map a buffer
1840 * without memory and we should be able to unmap that fine */
1841 if (G_LIKELY (info->memory)) {
1842 gst_memory_unmap (info->memory, info);
1843 gst_memory_unref (info->memory);
1849 * @buffer: a #GstBuffer.
1850 * @offset: the offset to fill
1851 * @src: (array length=size) (element-type guint8): the source address
1852 * @size: the size to fill
1854 * Copy @size bytes from @src to @buffer at @offset.
1856 * Returns: The amount of bytes copied. This value can be lower than @size
1857 * when @buffer did not contain enough data.
1860 gst_buffer_fill (GstBuffer * buffer, gsize offset, gconstpointer src,
1864 const guint8 *ptr = src;
1866 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1867 g_return_val_if_fail (gst_buffer_is_writable (buffer), 0);
1868 g_return_val_if_fail (src != NULL || size == 0, 0);
1870 GST_CAT_LOG (GST_CAT_BUFFER,
1871 "buffer %p, offset %" G_GSIZE_FORMAT ", size %" G_GSIZE_FORMAT, buffer,
1874 len = GST_BUFFER_MEM_LEN (buffer);
1877 for (i = 0; i < len && left > 0; i++) {
1882 mem = _get_mapped (buffer, i, &info, GST_MAP_WRITE);
1883 if (info.size > offset) {
1884 /* we have enough */
1885 tocopy = MIN (info.size - offset, left);
1886 memcpy ((guint8 *) info.data + offset, ptr, tocopy);
1891 /* offset past buffer, skip */
1892 offset -= info.size;
1894 gst_memory_unmap (mem, &info);
1900 * gst_buffer_extract:
1901 * @buffer: a #GstBuffer.
1902 * @offset: the offset to extract
1903 * @dest: (out caller-allocates) (array length=size) (element-type guint8):
1904 * the destination address
1905 * @size: the size to extract
1907 * Copy @size bytes starting from @offset in @buffer to @dest.
1909 * Returns: The amount of bytes extracted. This value can be lower than @size
1910 * when @buffer did not contain enough data.
1913 gst_buffer_extract (GstBuffer * buffer, gsize offset, gpointer dest, gsize size)
1918 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1919 g_return_val_if_fail (dest != NULL, 0);
1921 GST_CAT_LOG (GST_CAT_BUFFER,
1922 "buffer %p, offset %" G_GSIZE_FORMAT ", size %" G_GSIZE_FORMAT, buffer,
1925 len = GST_BUFFER_MEM_LEN (buffer);
1928 for (i = 0; i < len && left > 0; i++) {
1933 mem = _get_mapped (buffer, i, &info, GST_MAP_READ);
1934 if (info.size > offset) {
1935 /* we have enough */
1936 tocopy = MIN (info.size - offset, left);
1937 memcpy (ptr, (guint8 *) info.data + offset, tocopy);
1942 /* offset past buffer, skip */
1943 offset -= info.size;
1945 gst_memory_unmap (mem, &info);
1951 * gst_buffer_memcmp:
1952 * @buffer: a #GstBuffer.
1953 * @offset: the offset in @buffer
1954 * @mem: (array length=size) (element-type guint8): the memory to compare
1955 * @size: the size to compare
1957 * Compare @size bytes starting from @offset in @buffer with the memory in @mem.
1959 * Returns: 0 if the memory is equal.
1962 gst_buffer_memcmp (GstBuffer * buffer, gsize offset, gconstpointer mem,
1966 const guint8 *ptr = mem;
1969 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
1970 g_return_val_if_fail (mem != NULL, 0);
1972 GST_CAT_LOG (GST_CAT_BUFFER,
1973 "buffer %p, offset %" G_GSIZE_FORMAT ", size %" G_GSIZE_FORMAT, buffer,
1976 if (G_UNLIKELY (gst_buffer_get_size (buffer) < offset + size))
1979 len = GST_BUFFER_MEM_LEN (buffer);
1981 for (i = 0; i < len && size > 0 && res == 0; i++) {
1986 mem = _get_mapped (buffer, i, &info, GST_MAP_READ);
1987 if (info.size > offset) {
1988 /* we have enough */
1989 tocmp = MIN (info.size - offset, size);
1990 res = memcmp (ptr, (guint8 *) info.data + offset, tocmp);
1995 /* offset past buffer, skip */
1996 offset -= info.size;
1998 gst_memory_unmap (mem, &info);
2004 * gst_buffer_memset:
2005 * @buffer: a #GstBuffer.
2006 * @offset: the offset in @buffer
2007 * @val: the value to set
2008 * @size: the size to set
2010 * Fill @buf with @size bytes with @val starting from @offset.
2012 * Returns: The amount of bytes filled. This value can be lower than @size
2013 * when @buffer did not contain enough data.
2016 gst_buffer_memset (GstBuffer * buffer, gsize offset, guint8 val, gsize size)
2020 g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
2021 g_return_val_if_fail (gst_buffer_is_writable (buffer), 0);
2023 GST_CAT_LOG (GST_CAT_BUFFER,
2024 "buffer %p, offset %" G_GSIZE_FORMAT ", val %02x, size %" G_GSIZE_FORMAT,
2025 buffer, offset, val, size);
2027 len = GST_BUFFER_MEM_LEN (buffer);
2030 for (i = 0; i < len && left > 0; i++) {
2035 mem = _get_mapped (buffer, i, &info, GST_MAP_WRITE);
2036 if (info.size > offset) {
2037 /* we have enough */
2038 toset = MIN (info.size - offset, left);
2039 memset ((guint8 *) info.data + offset, val, toset);
2043 /* offset past buffer, skip */
2044 offset -= info.size;
2046 gst_memory_unmap (mem, &info);
2052 * gst_buffer_copy_region:
2053 * @parent: a #GstBuffer.
2054 * @flags: the #GstBufferCopyFlags
2055 * @offset: the offset into parent #GstBuffer at which the new sub-buffer
2057 * @size: the size of the new #GstBuffer sub-buffer, in bytes. If -1, all
2060 * Creates a sub-buffer from @parent at @offset and @size.
2061 * This sub-buffer uses the actual memory space of the parent buffer.
2062 * This function will copy the offset and timestamp fields when the
2063 * offset is 0. If not, they will be set to #GST_CLOCK_TIME_NONE and
2064 * #GST_BUFFER_OFFSET_NONE.
2065 * If @offset equals 0 and @size equals the total size of @buffer, the
2066 * duration and offset end fields are also copied. If not they will be set
2067 * to #GST_CLOCK_TIME_NONE and #GST_BUFFER_OFFSET_NONE.
2071 * Returns: (transfer full): the new #GstBuffer or %NULL if the arguments were
2075 gst_buffer_copy_region (GstBuffer * buffer, GstBufferCopyFlags flags,
2076 gsize offset, gsize size)
2080 g_return_val_if_fail (buffer != NULL, NULL);
2082 /* create the new buffer */
2083 copy = gst_buffer_new ();
2085 GST_CAT_LOG (GST_CAT_BUFFER, "new region copy %p of %p %" G_GSIZE_FORMAT
2086 "-%" G_GSIZE_FORMAT, copy, buffer, offset, size);
2088 if (!gst_buffer_copy_into (copy, buffer, flags, offset, size))
2089 gst_buffer_replace (©, NULL);
2095 * gst_buffer_append:
2096 * @buf1: (transfer full): the first source #GstBuffer to append.
2097 * @buf2: (transfer full): the second source #GstBuffer to append.
2099 * Append all the memory from @buf2 to @buf1. The result buffer will contain a
2100 * concatenation of the memory of @buf1 and @buf2.
2102 * Returns: (transfer full): the new #GstBuffer that contains the memory
2103 * of the two source buffers.
2106 gst_buffer_append (GstBuffer * buf1, GstBuffer * buf2)
2108 return gst_buffer_append_region (buf1, buf2, 0, -1);
2112 * gst_buffer_append_region:
2113 * @buf1: (transfer full): the first source #GstBuffer to append.
2114 * @buf2: (transfer full): the second source #GstBuffer to append.
2115 * @offset: the offset in @buf2
2116 * @size: the size or -1 of @buf2
2118 * Append @size bytes at @offset from @buf2 to @buf1. The result buffer will
2119 * contain a concatenation of the memory of @buf1 and the requested region of
2122 * Returns: (transfer full): the new #GstBuffer that contains the memory
2123 * of the two source buffers.
2126 gst_buffer_append_region (GstBuffer * buf1, GstBuffer * buf2, gssize offset,
2131 g_return_val_if_fail (GST_IS_BUFFER (buf1), NULL);
2132 g_return_val_if_fail (GST_IS_BUFFER (buf2), NULL);
2134 buf1 = gst_buffer_make_writable (buf1);
2135 buf2 = gst_buffer_make_writable (buf2);
2137 gst_buffer_resize (buf2, offset, size);
2139 len = GST_BUFFER_MEM_LEN (buf2);
2140 for (i = 0; i < len; i++) {
2143 mem = GST_BUFFER_MEM_PTR (buf2, i);
2144 gst_mini_object_remove_parent (GST_MINI_OBJECT_CAST (mem),
2145 GST_MINI_OBJECT_CAST (buf2));
2146 GST_BUFFER_MEM_PTR (buf2, i) = NULL;
2147 _memory_add (buf1, -1, mem);
2150 GST_BUFFER_MEM_LEN (buf2) = 0;
2151 GST_BUFFER_FLAG_SET (buf2, GST_BUFFER_FLAG_TAG_MEMORY);
2152 gst_buffer_unref (buf2);
2158 * gst_buffer_get_meta:
2159 * @buffer: a #GstBuffer
2160 * @api: the #GType of an API
2162 * Get the metadata for @api on buffer. When there is no such metadata, %NULL is
2163 * returned. If multiple metadata with the given @api are attached to this
2164 * buffer only the first one is returned. To handle multiple metadata with a
2165 * given API use gst_buffer_iterate_meta() or gst_buffer_foreach_meta() instead
2166 * and check the meta->info.api member for the API type.
2168 * Returns: (transfer none) (nullable): the metadata for @api on
2172 gst_buffer_get_meta (GstBuffer * buffer, GType api)
2175 GstMeta *result = NULL;
2177 g_return_val_if_fail (buffer != NULL, NULL);
2178 g_return_val_if_fail (api != 0, NULL);
2180 /* find GstMeta of the requested API */
2181 for (item = GST_BUFFER_META (buffer); item; item = item->next) {
2182 GstMeta *meta = &item->meta;
2183 if (meta->info->api == api) {
2192 * gst_buffer_get_n_meta:
2193 * @buffer: a #GstBuffer
2194 * @api_type: the #GType of an API
2196 * Returns: number of metas of type @api_type on @buffer.
2201 gst_buffer_get_n_meta (GstBuffer * buffer, GType api_type)
2203 gpointer state = NULL;
2207 while ((meta = gst_buffer_iterate_meta_filtered (buffer, &state, api_type)))
2214 * gst_buffer_add_meta:
2215 * @buffer: a #GstBuffer
2216 * @info: a #GstMetaInfo
2217 * @params: params for @info
2219 * Add metadata for @info to @buffer using the parameters in @params.
2221 * Returns: (transfer none) (nullable): the metadata for the api in @info on @buffer.
2224 gst_buffer_add_meta (GstBuffer * buffer, const GstMetaInfo * info,
2228 GstMeta *result = NULL;
2231 g_return_val_if_fail (buffer != NULL, NULL);
2232 g_return_val_if_fail (info != NULL, NULL);
2233 g_return_val_if_fail (gst_buffer_is_writable (buffer), NULL);
2235 /* create a new slice */
2236 size = ITEM_SIZE (info);
2237 /* We warn in gst_meta_register() about metas without
2238 * init function but let's play safe here and prevent
2239 * uninitialized memory
2241 if (!info->init_func)
2242 item = g_slice_alloc0 (size);
2244 item = g_slice_alloc (size);
2245 result = &item->meta;
2246 result->info = info;
2247 result->flags = GST_META_FLAG_NONE;
2248 GST_CAT_DEBUG (GST_CAT_BUFFER,
2249 "alloc metadata %p (%s) of size %" G_GSIZE_FORMAT, result,
2250 g_type_name (info->type), info->size);
2252 /* call the init_func when needed */
2253 if (info->init_func)
2254 if (!info->init_func (result, params, buffer))
2257 /* and add to the list of metadata */
2258 item->next = GST_BUFFER_META (buffer);
2259 GST_BUFFER_META (buffer) = item;
2265 g_slice_free1 (size, item);
2271 * gst_buffer_remove_meta:
2272 * @buffer: a #GstBuffer
2275 * Remove the metadata for @meta on @buffer.
2277 * Returns: %TRUE if the metadata existed and was removed, %FALSE if no such
2278 * metadata was on @buffer.
2281 gst_buffer_remove_meta (GstBuffer * buffer, GstMeta * meta)
2283 GstMetaItem *walk, *prev;
2285 g_return_val_if_fail (buffer != NULL, FALSE);
2286 g_return_val_if_fail (meta != NULL, FALSE);
2287 g_return_val_if_fail (gst_buffer_is_writable (buffer), FALSE);
2288 g_return_val_if_fail (!GST_META_FLAG_IS_SET (meta, GST_META_FLAG_LOCKED),
2291 /* find the metadata and delete */
2292 prev = GST_BUFFER_META (buffer);
2293 for (walk = prev; walk; walk = walk->next) {
2294 GstMeta *m = &walk->meta;
2296 const GstMetaInfo *info = meta->info;
2298 /* remove from list */
2299 if (GST_BUFFER_META (buffer) == walk)
2300 GST_BUFFER_META (buffer) = walk->next;
2302 prev->next = walk->next;
2303 /* call free_func if any */
2304 if (info->free_func)
2305 info->free_func (m, buffer);
2307 /* and free the slice */
2308 g_slice_free1 (ITEM_SIZE (info), walk);
2313 return walk != NULL;
2317 * gst_buffer_iterate_meta: (skip)
2318 * @buffer: a #GstBuffer
2319 * @state: (out caller-allocates): an opaque state pointer
2321 * Retrieve the next #GstMeta after @current. If @state points
2322 * to %NULL, the first metadata is returned.
2324 * @state will be updated with an opaque state pointer
2326 * Returns: (transfer none) (nullable): The next #GstMeta or %NULL
2327 * when there are no more items.
2330 gst_buffer_iterate_meta (GstBuffer * buffer, gpointer * state)
2334 g_return_val_if_fail (buffer != NULL, NULL);
2335 g_return_val_if_fail (state != NULL, NULL);
2337 meta = (GstMetaItem **) state;
2339 /* state NULL, move to first item */
2340 *meta = GST_BUFFER_META (buffer);
2342 /* state !NULL, move to next item in list */
2343 *meta = (*meta)->next;
2346 return &(*meta)->meta;
2352 * gst_buffer_iterate_meta_filtered: (skip)
2353 * @buffer: a #GstBuffer
2354 * @state: (out caller-allocates): an opaque state pointer
2355 * @meta_api_type: only return #GstMeta of this type
2357 * Retrieve the next #GstMeta of type @meta_api_type after the current one
2358 * according to @state. If @state points to %NULL, the first metadata of
2359 * type @meta_api_type is returned.
2361 * @state will be updated with an opaque state pointer
2363 * Returns: (transfer none) (nullable): The next #GstMeta of type
2364 * @meta_api_type or %NULL when there are no more items.
2369 gst_buffer_iterate_meta_filtered (GstBuffer * buffer, gpointer * state,
2370 GType meta_api_type)
2374 g_return_val_if_fail (buffer != NULL, NULL);
2375 g_return_val_if_fail (state != NULL, NULL);
2377 meta = (GstMetaItem **) state;
2379 /* state NULL, move to first item */
2380 *meta = GST_BUFFER_META (buffer);
2382 /* state !NULL, move to next item in list */
2383 *meta = (*meta)->next;
2385 while (*meta != NULL && (*meta)->meta.info->api != meta_api_type)
2386 *meta = (*meta)->next;
2389 return &(*meta)->meta;
2395 * gst_buffer_foreach_meta:
2396 * @buffer: a #GstBuffer
2397 * @func: (scope call): a #GstBufferForeachMetaFunc to call
2398 * @user_data: (closure): user data passed to @func
2400 * Call @func with @user_data for each meta in @buffer.
2402 * @func can modify the passed meta pointer or its contents. The return value
2403 * of @func define if this function returns or if the remaining metadata items
2404 * in the buffer should be skipped.
2406 * Returns: %FALSE when @func returned %FALSE for one of the metadata.
2409 gst_buffer_foreach_meta (GstBuffer * buffer, GstBufferForeachMetaFunc func,
2412 GstMetaItem *walk, *prev, *next;
2413 gboolean res = TRUE;
2415 g_return_val_if_fail (buffer != NULL, FALSE);
2416 g_return_val_if_fail (func != NULL, FALSE);
2418 /* find the metadata and delete */
2419 prev = GST_BUFFER_META (buffer);
2420 for (walk = prev; walk; walk = next) {
2423 m = new = &walk->meta;
2426 res = func (buffer, &new, user_data);
2429 const GstMetaInfo *info = m->info;
2431 GST_CAT_DEBUG (GST_CAT_BUFFER, "remove metadata %p (%s)", m,
2432 g_type_name (info->type));
2434 g_return_val_if_fail (gst_buffer_is_writable (buffer), FALSE);
2435 g_return_val_if_fail (!GST_META_FLAG_IS_SET (m, GST_META_FLAG_LOCKED),
2438 /* remove from list */
2439 if (GST_BUFFER_META (buffer) == walk)
2440 GST_BUFFER_META (buffer) = next;
2446 /* call free_func if any */
2447 if (info->free_func)
2448 info->free_func (m, buffer);
2450 /* and free the slice */
2451 g_slice_free1 (ITEM_SIZE (info), walk);
2462 * gst_buffer_extract_dup:
2463 * @buffer: a #GstBuffer
2464 * @offset: the offset to extract
2465 * @size: the size to extract
2466 * @dest: (array length=dest_size) (element-type guint8) (out): A pointer where
2467 * the destination array will be written. Might be %NULL if the size is 0.
2468 * @dest_size: (out): A location where the size of @dest can be written
2470 * Extracts a copy of at most @size bytes the data at @offset into
2471 * newly-allocated memory. @dest must be freed using g_free() when done.
2477 gst_buffer_extract_dup (GstBuffer * buffer, gsize offset, gsize size,
2478 gpointer * dest, gsize * dest_size)
2480 gsize real_size, alloc_size;
2482 real_size = gst_buffer_get_size (buffer);
2484 alloc_size = MIN (real_size - offset, size);
2485 if (alloc_size == 0) {
2489 *dest = g_malloc (alloc_size);
2490 *dest_size = gst_buffer_extract (buffer, offset, *dest, size);
2494 GST_DEBUG_CATEGORY_STATIC (gst_parent_buffer_meta_debug);
2497 * gst_buffer_add_parent_buffer_meta:
2498 * @buffer: (transfer none): a #GstBuffer
2499 * @ref: (transfer none): a #GstBuffer to ref
2501 * Add a #GstParentBufferMeta to @buffer that holds a reference on
2502 * @ref until the buffer is freed.
2504 * Returns: (transfer none) (nullable): The #GstParentBufferMeta that was added to the buffer
2508 GstParentBufferMeta *
2509 gst_buffer_add_parent_buffer_meta (GstBuffer * buffer, GstBuffer * ref)
2511 GstParentBufferMeta *meta;
2513 g_return_val_if_fail (GST_IS_BUFFER (ref), NULL);
2516 (GstParentBufferMeta *) gst_buffer_add_meta (buffer,
2517 GST_PARENT_BUFFER_META_INFO, NULL);
2522 meta->buffer = gst_buffer_ref (ref);
2528 _gst_parent_buffer_meta_transform (GstBuffer * dest, GstMeta * meta,
2529 GstBuffer * buffer, GQuark type, gpointer data)
2531 GstParentBufferMeta *dmeta, *smeta;
2533 smeta = (GstParentBufferMeta *) meta;
2535 if (GST_META_TRANSFORM_IS_COPY (type)) {
2536 /* copy over the reference to the parent buffer.
2537 * Usually, this meta means we need to keep the parent buffer
2538 * alive because one of the child memories is in use, which
2539 * might not be the case if memory is deep copied or sub-regioned,
2540 * but we can't tell, so keep the meta */
2541 dmeta = gst_buffer_add_parent_buffer_meta (dest, smeta->buffer);
2545 GST_CAT_DEBUG (gst_parent_buffer_meta_debug,
2546 "copy buffer reference metadata");
2548 /* return FALSE, if transform type is not supported */
2555 _gst_parent_buffer_meta_free (GstParentBufferMeta * parent_meta,
2558 GST_CAT_DEBUG (gst_parent_buffer_meta_debug,
2559 "Dropping reference on buffer %p", parent_meta->buffer);
2560 gst_buffer_unref (parent_meta->buffer);
2564 _gst_parent_buffer_meta_init (GstParentBufferMeta * parent_meta,
2565 gpointer params, GstBuffer * buffer)
2567 static volatile gsize _init;
2569 if (g_once_init_enter (&_init)) {
2570 GST_DEBUG_CATEGORY_INIT (gst_parent_buffer_meta_debug, "parentbuffermeta",
2571 0, "parentbuffermeta");
2572 g_once_init_leave (&_init, 1);
2575 parent_meta->buffer = NULL;
2581 gst_parent_buffer_meta_api_get_type (void)
2583 static volatile GType type = 0;
2584 static const gchar *tags[] = { NULL };
2586 if (g_once_init_enter (&type)) {
2587 GType _type = gst_meta_api_type_register ("GstParentBufferMetaAPI", tags);
2588 g_once_init_leave (&type, _type);
2595 * gst_parent_buffer_meta_get_info:
2597 * Get the global #GstMetaInfo describing the #GstParentBufferMeta meta.
2599 * Returns: (transfer none): The #GstMetaInfo
2604 gst_parent_buffer_meta_get_info (void)
2606 static const GstMetaInfo *meta_info = NULL;
2608 if (g_once_init_enter ((GstMetaInfo **) & meta_info)) {
2609 const GstMetaInfo *meta =
2610 gst_meta_register (gst_parent_buffer_meta_api_get_type (),
2611 "GstParentBufferMeta",
2612 sizeof (GstParentBufferMeta),
2613 (GstMetaInitFunction) _gst_parent_buffer_meta_init,
2614 (GstMetaFreeFunction) _gst_parent_buffer_meta_free,
2615 _gst_parent_buffer_meta_transform);
2616 g_once_init_leave ((GstMetaInfo **) & meta_info, (GstMetaInfo *) meta);
2622 GST_DEBUG_CATEGORY_STATIC (gst_reference_timestamp_meta_debug);
2625 * gst_buffer_add_reference_timestamp_meta:
2626 * @buffer: (transfer none): a #GstBuffer
2627 * @reference: (transfer none): identifier for the timestamp reference.
2628 * @timestamp: timestamp
2629 * @duration: duration, or %GST_CLOCK_TIME_NONE
2631 * Add a #GstReferenceTimestampMeta to @buffer that holds a @timestamp and
2632 * optionally @duration based on a specific timestamp @reference. See the
2633 * documentation of #GstReferenceTimestampMeta for details.
2635 * Returns: (transfer none) (nullable): The #GstReferenceTimestampMeta that was added to the buffer
2639 GstReferenceTimestampMeta *
2640 gst_buffer_add_reference_timestamp_meta (GstBuffer * buffer,
2641 GstCaps * reference, GstClockTime timestamp, GstClockTime duration)
2643 GstReferenceTimestampMeta *meta;
2645 g_return_val_if_fail (GST_IS_CAPS (reference), NULL);
2646 g_return_val_if_fail (timestamp != GST_CLOCK_TIME_NONE, NULL);
2649 (GstReferenceTimestampMeta *) gst_buffer_add_meta (buffer,
2650 GST_REFERENCE_TIMESTAMP_META_INFO, NULL);
2655 meta->reference = gst_caps_ref (reference);
2656 meta->timestamp = timestamp;
2657 meta->duration = duration;
2663 * gst_buffer_get_reference_timestamp_meta:
2664 * @buffer: a #GstBuffer
2665 * @reference: (allow-none): a reference #GstCaps
2667 * Find the first #GstReferenceTimestampMeta on @buffer that conforms to
2668 * @reference. Conformance is tested by checking if the meta's reference is a
2669 * subset of @reference.
2671 * Buffers can contain multiple #GstReferenceTimestampMeta metadata items.
2673 * Returns: (transfer none) (nullable): the #GstReferenceTimestampMeta or %NULL when there
2674 * is no such metadata on @buffer.
2678 GstReferenceTimestampMeta *
2679 gst_buffer_get_reference_timestamp_meta (GstBuffer * buffer,
2680 GstCaps * reference)
2682 gpointer state = NULL;
2684 const GstMetaInfo *info = GST_REFERENCE_TIMESTAMP_META_INFO;
2686 while ((meta = gst_buffer_iterate_meta (buffer, &state))) {
2687 if (meta->info->api == info->api) {
2688 GstReferenceTimestampMeta *rmeta = (GstReferenceTimestampMeta *) meta;
2692 if (gst_caps_is_subset (rmeta->reference, reference))
2700 _gst_reference_timestamp_meta_transform (GstBuffer * dest, GstMeta * meta,
2701 GstBuffer * buffer, GQuark type, gpointer data)
2703 GstReferenceTimestampMeta *dmeta, *smeta;
2705 /* we copy over the reference timestamp meta, independent of transformation
2706 * that happens. If it applied to the original buffer, it still applies to
2707 * the new buffer as it refers to the time when the media was captured */
2708 smeta = (GstReferenceTimestampMeta *) meta;
2710 gst_buffer_add_reference_timestamp_meta (dest, smeta->reference,
2711 smeta->timestamp, smeta->duration);
2715 GST_CAT_DEBUG (gst_reference_timestamp_meta_debug,
2716 "copy reference timestamp metadata from buffer %p to %p", buffer, dest);
2722 _gst_reference_timestamp_meta_free (GstReferenceTimestampMeta * meta,
2725 if (meta->reference)
2726 gst_caps_unref (meta->reference);
2730 _gst_reference_timestamp_meta_init (GstReferenceTimestampMeta * meta,
2731 gpointer params, GstBuffer * buffer)
2733 static volatile gsize _init;
2735 if (g_once_init_enter (&_init)) {
2736 GST_DEBUG_CATEGORY_INIT (gst_reference_timestamp_meta_debug,
2737 "referencetimestampmeta", 0, "referencetimestampmeta");
2738 g_once_init_leave (&_init, 1);
2741 meta->reference = NULL;
2742 meta->timestamp = GST_CLOCK_TIME_NONE;
2743 meta->duration = GST_CLOCK_TIME_NONE;
2749 gst_reference_timestamp_meta_api_get_type (void)
2751 static volatile GType type = 0;
2752 static const gchar *tags[] = { NULL };
2754 if (g_once_init_enter (&type)) {
2756 gst_meta_api_type_register ("GstReferenceTimestampMetaAPI", tags);
2757 g_once_init_leave (&type, _type);
2764 * gst_reference_timestamp_meta_get_info:
2766 * Get the global #GstMetaInfo describing the #GstReferenceTimestampMeta meta.
2768 * Returns: (transfer none): The #GstMetaInfo
2773 gst_reference_timestamp_meta_get_info (void)
2775 static const GstMetaInfo *meta_info = NULL;
2777 if (g_once_init_enter ((GstMetaInfo **) & meta_info)) {
2778 const GstMetaInfo *meta =
2779 gst_meta_register (gst_reference_timestamp_meta_api_get_type (),
2780 "GstReferenceTimestampMeta",
2781 sizeof (GstReferenceTimestampMeta),
2782 (GstMetaInitFunction) _gst_reference_timestamp_meta_init,
2783 (GstMetaFreeFunction) _gst_reference_timestamp_meta_free,
2784 _gst_reference_timestamp_meta_transform);
2785 g_once_init_leave ((GstMetaInfo **) & meta_info, (GstMetaInfo *) meta);