1/* GStreamer
2 * Copyright (C) 1999,2000 Erik Walthinsen <[email protected]>
3 * 2000 Wim Taymans <[email protected]>
4 *
5 * gstbuffer.h: Header for GstBuffer object
6 *
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.
11 *
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.
16 *
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.
21 */
22
23
24#ifndef __GST_BUFFER_H__
25#define __GST_BUFFER_H__
26
27#include <gst/gstminiobject.h>
28#include <gst/gstclock.h>
29#include <gst/gstallocator.h>
30#include <gst/gstcaps.h>
31
32G_BEGIN_DECLS
33
34GST_API GType _gst_buffer_type;
35
36typedef struct _GstBuffer GstBuffer;
37typedef struct _GstBufferPool GstBufferPool;
38
39#include <gst/gstmeta.h>
40
41#define GST_TYPE_BUFFER (_gst_buffer_type)
42#define GST_IS_BUFFER(obj) (GST_IS_MINI_OBJECT_TYPE(obj, GST_TYPE_BUFFER))
43#define GST_BUFFER_CAST(obj) ((GstBuffer *)(obj))
44#define GST_BUFFER(obj) (GST_BUFFER_CAST(obj))
45
46/**
47 * GST_BUFFER_FLAGS:
48 * @buf: a #GstBuffer.
49 *
50 * A flags word containing #GstBufferFlags flags set on this buffer.
51 */
52#define GST_BUFFER_FLAGS(buf) GST_MINI_OBJECT_FLAGS(buf)
53/**
54 * GST_BUFFER_FLAG_IS_SET:
55 * @buf: a #GstBuffer.
56 * @flag: the #GstBufferFlags flag to check.
57 *
58 * Gives the status of a specific flag on a buffer.
59 */
60#define GST_BUFFER_FLAG_IS_SET(buf,flag) GST_MINI_OBJECT_FLAG_IS_SET (buf, flag)
61/**
62 * GST_BUFFER_FLAG_SET:
63 * @buf: a #GstBuffer.
64 * @flag: the #GstBufferFlags flag to set.
65 *
66 * Sets a buffer flag on a buffer.
67 */
68#define GST_BUFFER_FLAG_SET(buf,flag) GST_MINI_OBJECT_FLAG_SET (buf, flag)
69/**
70 * GST_BUFFER_FLAG_UNSET:
71 * @buf: a #GstBuffer.
72 * @flag: the #GstBufferFlags flag to clear.
73 *
74 * Clears a buffer flag.
75 */
76#define GST_BUFFER_FLAG_UNSET(buf,flag) GST_MINI_OBJECT_FLAG_UNSET (buf, flag)
77
78
79/**
80 * GST_BUFFER_PTS:
81 * @buf: a #GstBuffer.:
82 *
83 * The presentation timestamp (pts) in nanoseconds (as a #GstClockTime)
84 * of the data in the buffer. This is the timestamp when the media should be
85 * presented to the user.
86 * Value will be %GST_CLOCK_TIME_NONE if the pts is unknown.
87 */
88#define GST_BUFFER_PTS(buf) (GST_BUFFER_CAST(buf)->pts)
89/**
90 * GST_BUFFER_DTS:
91 * @buf: a #GstBuffer.:
92 *
93 * The decoding timestamp (dts) in nanoseconds (as a #GstClockTime)
94 * of the data in the buffer. This is the timestamp when the media should be
95 * decoded or processed otherwise.
96 * Value will be %GST_CLOCK_TIME_NONE if the dts is unknown.
97 */
98#define GST_BUFFER_DTS(buf) (GST_BUFFER_CAST(buf)->dts)
99/**
100 * GST_BUFFER_DTS_OR_PTS:
101 * @buf: a #GstBuffer.:
102 *
103 * Returns the buffer decoding timestamp (dts) if valid, else the buffer
104 * presentation time (pts)
105 *
106 * Since: 1.8
107 */
108#define GST_BUFFER_DTS_OR_PTS(buf) (GST_BUFFER_DTS_IS_VALID(buf) ? GST_BUFFER_DTS(buf) : GST_BUFFER_PTS (buf))
109/**
110 * GST_BUFFER_DURATION:
111 * @buf: a #GstBuffer.
112 *
113 * The duration in nanoseconds (as a #GstClockTime) of the data in the buffer.
114 * Value will be %GST_CLOCK_TIME_NONE if the duration is unknown.
115 */
116#define GST_BUFFER_DURATION(buf) (GST_BUFFER_CAST(buf)->duration)
117/**
118 * GST_BUFFER_OFFSET:
119 * @buf: a #GstBuffer.
120 *
121 * The offset in the source file of the beginning of this buffer.
122 */
123#define GST_BUFFER_OFFSET(buf) (GST_BUFFER_CAST(buf)->offset)
124/**
125 * GST_BUFFER_OFFSET_END:
126 * @buf: a #GstBuffer.
127 *
128 * The offset in the source file of the end of this buffer.
129 */
130#define GST_BUFFER_OFFSET_END(buf) (GST_BUFFER_CAST(buf)->offset_end)
131
132/**
133 * GST_BUFFER_OFFSET_NONE:
134 *
135 * Constant for no-offset return results.
136 */
137#define GST_BUFFER_OFFSET_NONE ((guint64)-1)
138
139/**
140 * GST_BUFFER_DURATION_IS_VALID:
141 * @buffer: a #GstBuffer
142 *
143 * Tests if the duration is known.
144 */
145#define GST_BUFFER_DURATION_IS_VALID(buffer) (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_DURATION (buffer)))
146/**
147 * GST_BUFFER_PTS_IS_VALID:
148 * @buffer: a #GstBuffer
149 *
150 * Tests if the pts is known.
151 */
152#define GST_BUFFER_PTS_IS_VALID(buffer) (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_PTS (buffer)))
153/**
154 * GST_BUFFER_DTS_IS_VALID:
155 * @buffer: a #GstBuffer
156 *
157 * Tests if the dts is known.
158 */
159#define GST_BUFFER_DTS_IS_VALID(buffer) (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_DTS (buffer)))
160/**
161 * GST_BUFFER_OFFSET_IS_VALID:
162 * @buffer: a #GstBuffer
163 *
164 * Tests if the start offset is known.
165 */
166#define GST_BUFFER_OFFSET_IS_VALID(buffer) (GST_BUFFER_OFFSET (buffer) != GST_BUFFER_OFFSET_NONE)
167/**
168 * GST_BUFFER_OFFSET_END_IS_VALID:
169 * @buffer: a #GstBuffer
170 *
171 * Tests if the end offset is known.
172 */
173#define GST_BUFFER_OFFSET_END_IS_VALID(buffer) (GST_BUFFER_OFFSET_END (buffer) != GST_BUFFER_OFFSET_NONE)
174/**
175 * GST_BUFFER_IS_DISCONT:
176 * @buffer: a #GstBuffer
177 *
178 * Tests if the buffer marks a discontinuity in the stream.
179 */
180#define GST_BUFFER_IS_DISCONT(buffer) (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_DISCONT))
181
182/**
183 * GstBufferFlags:
184 * @GST_BUFFER_FLAG_LIVE: the buffer is live data and should be discarded in
185 * the PAUSED state.
186 * @GST_BUFFER_FLAG_DECODE_ONLY: the buffer contains data that should be dropped
187 * because it will be clipped against the segment
188 * boundaries or because it does not contain data
189 * that should be shown to the user.
190 * @GST_BUFFER_FLAG_DISCONT: the buffer marks a data discontinuity in the stream.
191 * This typically occurs after a seek or a dropped buffer
192 * from a live or network source.
193 * @GST_BUFFER_FLAG_RESYNC: the buffer timestamps might have a discontinuity
194 * and this buffer is a good point to resynchronize.
195 * @GST_BUFFER_FLAG_CORRUPTED: the buffer data is corrupted.
196 * @GST_BUFFER_FLAG_MARKER: the buffer contains a media specific marker. for
197 * video this is typically the end of a frame boundary, for audio
198 * this is usually the start of a talkspurt.
199 * @GST_BUFFER_FLAG_HEADER: the buffer contains header information that is
200 * needed to decode the following data.
201 * @GST_BUFFER_FLAG_GAP: the buffer has been created to fill a gap in the
202 * stream and contains media neutral data (elements can
203 * switch to optimized code path that ignores the buffer
204 * content).
205 * @GST_BUFFER_FLAG_DROPPABLE: the buffer can be dropped without breaking the
206 * stream, for example to reduce bandwidth.
207 * @GST_BUFFER_FLAG_DELTA_UNIT: this unit cannot be decoded independently.
208 * @GST_BUFFER_FLAG_TAG_MEMORY: this flag is set when memory of the buffer
209 * is added/removed
210 * @GST_BUFFER_FLAG_SYNC_AFTER: Elements which write to disk or permanent
211 * storage should ensure the data is synced after
212 * writing the contents of this buffer. (Since 1.6)
213 * @GST_BUFFER_FLAG_NON_DROPPABLE: This buffer is important and should not be dropped.
214 * This can be used to mark important buffers, e.g. to flag
215 * RTP packets carrying keyframes or codec setup data for RTP
216 * Forward Error Correction purposes, or to prevent still video
217 * frames from being dropped by elements due to QoS. (Since 1.14)
218 * @GST_BUFFER_FLAG_LAST: additional media specific flags can be added starting from
219 * this flag.
220 *
221 * A set of buffer flags used to describe properties of a #GstBuffer.
222 */
223typedef enum {
224 GST_BUFFER_FLAG_LIVE = (GST_MINI_OBJECT_FLAG_LAST << 0),
225 GST_BUFFER_FLAG_DECODE_ONLY = (GST_MINI_OBJECT_FLAG_LAST << 1),
226 GST_BUFFER_FLAG_DISCONT = (GST_MINI_OBJECT_FLAG_LAST << 2),
227 GST_BUFFER_FLAG_RESYNC = (GST_MINI_OBJECT_FLAG_LAST << 3),
228 GST_BUFFER_FLAG_CORRUPTED = (GST_MINI_OBJECT_FLAG_LAST << 4),
229 GST_BUFFER_FLAG_MARKER = (GST_MINI_OBJECT_FLAG_LAST << 5),
230 GST_BUFFER_FLAG_HEADER = (GST_MINI_OBJECT_FLAG_LAST << 6),
231 GST_BUFFER_FLAG_GAP = (GST_MINI_OBJECT_FLAG_LAST << 7),
232 GST_BUFFER_FLAG_DROPPABLE = (GST_MINI_OBJECT_FLAG_LAST << 8),
233 GST_BUFFER_FLAG_DELTA_UNIT = (GST_MINI_OBJECT_FLAG_LAST << 9),
234 GST_BUFFER_FLAG_TAG_MEMORY = (GST_MINI_OBJECT_FLAG_LAST << 10),
235 GST_BUFFER_FLAG_SYNC_AFTER = (GST_MINI_OBJECT_FLAG_LAST << 11),
236 GST_BUFFER_FLAG_NON_DROPPABLE = (GST_MINI_OBJECT_FLAG_LAST << 12),
237
238 GST_BUFFER_FLAG_LAST = (GST_MINI_OBJECT_FLAG_LAST << 16)
239} GstBufferFlags;
240
241/**
242 * GstBuffer:
243 * @mini_object: the parent structure
244 * @pool: pointer to the pool owner of the buffer
245 * @pts: presentation timestamp of the buffer, can be #GST_CLOCK_TIME_NONE when the
246 * pts is not known or relevant. The pts contains the timestamp when the
247 * media should be presented to the user.
248 * @dts: decoding timestamp of the buffer, can be #GST_CLOCK_TIME_NONE when the
249 * dts is not known or relevant. The dts contains the timestamp when the
250 * media should be processed.
251 * @duration: duration in time of the buffer data, can be #GST_CLOCK_TIME_NONE
252 * when the duration is not known or relevant.
253 * @offset: a media specific offset for the buffer data.
254 * For video frames, this is the frame number of this buffer.
255 * For audio samples, this is the offset of the first sample in this buffer.
256 * For file data or compressed data this is the byte offset of the first
257 * byte in this buffer.
258 * @offset_end: the last offset contained in this buffer. It has the same
259 * format as @offset.
260 *
261 * The structure of a #GstBuffer. Use the associated macros to access the public
262 * variables.
263 */
264struct _GstBuffer {
265 GstMiniObject mini_object;
266
267 /*< public >*/ /* with COW */
268 GstBufferPool *pool;
269
270 /* timestamp */
271 GstClockTime pts;
272 GstClockTime dts;
273 GstClockTime duration;
274
275 /* media specific offset */
276 guint64 offset;
277 guint64 offset_end;
278};
279
280GST_API
281GType gst_buffer_get_type (void);
282
283GST_API
284guint gst_buffer_get_max_memory (void);
285
286/* allocation */
287
288GST_API
289GstBuffer * gst_buffer_new (void);
290
291GST_API
292GstBuffer * gst_buffer_new_allocate (GstAllocator * allocator, gsize size,
293 GstAllocationParams * params);
294GST_API
295GstBuffer * gst_buffer_new_wrapped_full (GstMemoryFlags flags, gpointer data, gsize maxsize,
296 gsize offset, gsize size, gpointer user_data,
297 GDestroyNotify notify);
298GST_API
299GstBuffer * gst_buffer_new_wrapped (gpointer data, gsize size);
300GST_API
301GstBuffer * gst_buffer_new_wrapped_bytes (GBytes * bytes);
302
303/* memory blocks */
304
305GST_API
306guint gst_buffer_n_memory (GstBuffer *buffer);
307
308GST_API
309void gst_buffer_insert_memory (GstBuffer *buffer, gint idx, GstMemory *mem);
310
311GST_API
312void gst_buffer_replace_memory_range (GstBuffer *buffer, guint idx, gint length, GstMemory *mem);
313
314GST_API
315GstMemory * gst_buffer_peek_memory (GstBuffer *buffer, guint idx);
316
317GST_API
318GstMemory * gst_buffer_get_memory_range (GstBuffer *buffer, guint idx, gint length);
319
320GST_API
321void gst_buffer_remove_memory_range (GstBuffer *buffer, guint idx, gint length);
322
323GST_API
324void gst_buffer_prepend_memory (GstBuffer *buffer, GstMemory *mem);
325
326GST_API
327void gst_buffer_append_memory (GstBuffer *buffer, GstMemory *mem);
328
329GST_API
330void gst_buffer_replace_memory (GstBuffer *buffer, guint idx, GstMemory *mem);
331
332GST_API
333void gst_buffer_replace_all_memory (GstBuffer *buffer, GstMemory *mem);
334
335GST_API
336GstMemory * gst_buffer_get_memory (GstBuffer *buffer, guint idx);
337
338GST_API
339GstMemory * gst_buffer_get_all_memory (GstBuffer *buffer);
340
341GST_API
342void gst_buffer_remove_memory (GstBuffer *buffer, guint idx);
343
344GST_API
345void gst_buffer_remove_all_memory (GstBuffer *buffer);
346
347GST_API
348gboolean gst_buffer_find_memory (GstBuffer *buffer, gsize offset, gsize size,
349 guint *idx, guint *length, gsize *skip);
350GST_API
351gboolean gst_buffer_is_memory_range_writable (GstBuffer *buffer, guint idx, gint length);
352
353GST_API
354gboolean gst_buffer_is_all_memory_writable (GstBuffer *buffer);
355
356GST_API
357gsize gst_buffer_fill (GstBuffer *buffer, gsize offset,
358 gconstpointer src, gsize size);
359GST_API
360gsize gst_buffer_extract (GstBuffer *buffer, gsize offset,
361 gpointer dest, gsize size);
362GST_API
363gint gst_buffer_memcmp (GstBuffer *buffer, gsize offset,
364 gconstpointer mem, gsize size);
365GST_API
366gsize gst_buffer_memset (GstBuffer *buffer, gsize offset,
367 guint8 val, gsize size);
368GST_API
369gsize gst_buffer_get_sizes_range (GstBuffer *buffer, guint idx, gint length,
370 gsize *offset, gsize *maxsize);
371GST_API
372gboolean gst_buffer_resize_range (GstBuffer *buffer, guint idx, gint length,
373 gssize offset, gssize size);
374GST_API
375gsize gst_buffer_get_sizes (GstBuffer *buffer, gsize *offset, gsize *maxsize);
376
377GST_API
378gsize gst_buffer_get_size (GstBuffer *buffer);
379
380GST_API
381void gst_buffer_resize (GstBuffer *buffer, gssize offset, gssize size);
382
383GST_API
384void gst_buffer_set_size (GstBuffer *buffer, gssize size);
385
386GST_API
387gboolean gst_buffer_map_range (GstBuffer *buffer, guint idx, gint length,
388 GstMapInfo *info, GstMapFlags flags);
389GST_API
390gboolean gst_buffer_map (GstBuffer *buffer, GstMapInfo *info, GstMapFlags flags);
391
392GST_API
393void gst_buffer_unmap (GstBuffer *buffer, GstMapInfo *info);
394
395GST_API
396void gst_buffer_extract_dup (GstBuffer *buffer, gsize offset,
397 gsize size, gpointer *dest,
398 gsize *dest_size);
399GST_API
400GstBufferFlags gst_buffer_get_flags (GstBuffer * buffer);
401
402GST_API
403gboolean gst_buffer_has_flags (GstBuffer * buffer, GstBufferFlags flags);
404
405GST_API
406gboolean gst_buffer_set_flags (GstBuffer * buffer, GstBufferFlags flags);
407
408GST_API
409gboolean gst_buffer_unset_flags (GstBuffer * buffer, GstBufferFlags flags);
410
411
412
413/* refcounting */
414/**
415 * gst_buffer_ref:
416 * @buf: a #GstBuffer.
417 *
418 * Increases the refcount of the given buffer by one.
419 *
420 * Note that the refcount affects the writability
421 * of @buf and its metadata, see gst_buffer_is_writable().
422 * It is important to note that keeping additional references to
423 * GstBuffer instances can potentially increase the number
424 * of memcpy operations in a pipeline.
425 *
426 * Returns: (transfer full): @buf
427 */
428static inline GstBuffer *
429gst_buffer_ref (GstBuffer * buf)
430{
431 return (GstBuffer *) gst_mini_object_ref (GST_MINI_OBJECT_CAST (buf));
432}
433
434/**
435 * gst_buffer_unref:
436 * @buf: (transfer full): a #GstBuffer.
437 *
438 * Decreases the refcount of the buffer. If the refcount reaches 0, the buffer
439 * with the associated metadata and memory will be freed.
440 */
441static inline void
442gst_buffer_unref (GstBuffer * buf)
443{
444 gst_mini_object_unref (GST_MINI_OBJECT_CAST (buf));
445}
446
447/**
448 * gst_clear_buffer: (skip)
449 * @buf_ptr: a pointer to a #GstBuffer reference
450 *
451 * Clears a reference to a #GstBuffer.
452 *
453 * @buf_ptr must not be %NULL.
454 *
455 * If the reference is %NULL then this function does nothing. Otherwise, the
456 * reference count of the buffer is decreased and the pointer is set to %NULL.
457 *
458 * Since: 1.16
459 */
460static inline void
461gst_clear_buffer (GstBuffer ** buf_ptr)
462{
463 gst_clear_mini_object ((GstMiniObject **) buf_ptr);
464}
465
466/* copy buffer */
467/**
468 * gst_buffer_copy:
469 * @buf: a #GstBuffer.
470 *
471 * Create a copy of the given buffer. This will only copy the buffer's
472 * data to a newly allocated memory if needed (if the type of memory
473 * requires it), otherwise the underlying data is just referenced.
474 * Check gst_buffer_copy_deep() if you want to force the data
475 * to be copied to newly allocated memory.
476 *
477 * Returns: (transfer full): a new copy of @buf.
478 */
479static inline GstBuffer *
480gst_buffer_copy (const GstBuffer * buf)
481{
482 return GST_BUFFER (gst_mini_object_copy (GST_MINI_OBJECT_CONST_CAST (buf)));
483}
484
485GST_API
486GstBuffer * gst_buffer_copy_deep (const GstBuffer * buf);
487
488/**
489 * GstBufferCopyFlags:
490 * @GST_BUFFER_COPY_NONE: copy nothing
491 * @GST_BUFFER_COPY_FLAGS: flag indicating that buffer flags should be copied
492 * @GST_BUFFER_COPY_TIMESTAMPS: flag indicating that buffer pts, dts,
493 * duration, offset and offset_end should be copied
494 * @GST_BUFFER_COPY_MEMORY: flag indicating that buffer memory should be reffed
495 * and appended to already existing memory. Unless the memory is marked as
496 * NO_SHARE, no actual copy of the memory is made but it is simply reffed.
497 * Add @GST_BUFFER_COPY_DEEP to force a real copy.
498 * @GST_BUFFER_COPY_MERGE: flag indicating that buffer memory should be
499 * merged
500 * @GST_BUFFER_COPY_META: flag indicating that buffer meta should be
501 * copied
502 * @GST_BUFFER_COPY_DEEP: flag indicating that memory should always be
503 * copied instead of reffed (Since 1.2)
504 *
505 * A set of flags that can be provided to the gst_buffer_copy_into()
506 * function to specify which items should be copied.
507 */
508typedef enum {
509 GST_BUFFER_COPY_NONE = 0,
510 GST_BUFFER_COPY_FLAGS = (1 << 0),
511 GST_BUFFER_COPY_TIMESTAMPS = (1 << 1),
512 GST_BUFFER_COPY_META = (1 << 2),
513 GST_BUFFER_COPY_MEMORY = (1 << 3),
514 GST_BUFFER_COPY_MERGE = (1 << 4),
515 GST_BUFFER_COPY_DEEP = (1 << 5)
516} GstBufferCopyFlags;
517
518/**
519 * GST_BUFFER_COPY_METADATA: (value 7) (type GstBufferCopyFlags)
520 *
521 * Combination of all possible metadata fields that can be copied with
522 * gst_buffer_copy_into().
523 */
524#define GST_BUFFER_COPY_METADATA ((GstBufferCopyFlags) (GST_BUFFER_COPY_FLAGS |\
525 GST_BUFFER_COPY_TIMESTAMPS | GST_BUFFER_COPY_META))
526
527/**
528 * GST_BUFFER_COPY_ALL: (value 15) (type GstBufferCopyFlags)
529 *
530 * Combination of all possible fields that can be copied with
531 * gst_buffer_copy_into().
532 */
533#define GST_BUFFER_COPY_ALL ((GstBufferCopyFlags)(GST_BUFFER_COPY_METADATA | GST_BUFFER_COPY_MEMORY))
534
535/* copies memory or metadata into newly allocated buffer */
536
537GST_API
538gboolean gst_buffer_copy_into (GstBuffer *dest, GstBuffer *src,
539 GstBufferCopyFlags flags,
540 gsize offset, gsize size);
541
542/**
543 * gst_buffer_is_writable:
544 * @buf: a #GstBuffer
545 *
546 * Tests if you can safely write to a buffer's metadata or its memory array.
547 * It is only safe to change buffer metadata when the current reference is
548 * writable, i.e. nobody can see the modifications you will make.
549 */
550#define gst_buffer_is_writable(buf) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (buf))
551/**
552 * gst_buffer_make_writable:
553 * @buf: (transfer full): a #GstBuffer
554 *
555 * Returns a writable copy of @buf. If the source buffer is
556 * already writable, this will simply return the same buffer.
557 *
558 * Use this function to ensure that a buffer can be safely modified before
559 * making changes to it, including changing the metadata such as PTS/DTS.
560 *
561 * If the reference count of the source buffer @buf is exactly one, the caller
562 * is the sole owner and this function will return the buffer object unchanged.
563 *
564 * If there is more than one reference on the object, a copy will be made using
565 * gst_buffer_copy(). The passed-in @buf will be unreffed in that case, and the
566 * caller will now own a reference to the new returned buffer object. Note
567 * that this just copies the buffer structure itself, the underlying memory is
568 * not copied if it can be shared amongst multiple buffers.
569 *
570 * In short, this function unrefs the buf in the argument and refs the buffer
571 * that it returns. Don't access the argument after calling this function unless
572 * you have an additional reference to it.
573 *
574 * Returns: (transfer full): a writable buffer which may or may not be the
575 * same as @buf
576 */
577#define gst_buffer_make_writable(buf) GST_BUFFER_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (buf)))
578
579/**
580 * gst_buffer_replace:
581 * @obuf: (inout) (transfer full) (nullable): pointer to a pointer to
582 * a #GstBuffer to be replaced.
583 * @nbuf: (transfer none) (allow-none): pointer to a #GstBuffer that will
584 * replace the buffer pointed to by @obuf.
585 *
586 * Modifies a pointer to a #GstBuffer to point to a different #GstBuffer. The
587 * modification is done atomically (so this is useful for ensuring thread safety
588 * in some cases), and the reference counts are updated appropriately (the old
589 * buffer is unreffed, the new is reffed).
590 *
591 * Either @nbuf or the #GstBuffer pointed to by @obuf may be %NULL.
592 *
593 * Returns: %TRUE when @obuf was different from @nbuf.
594 */
595static inline gboolean
596gst_buffer_replace (GstBuffer **obuf, GstBuffer *nbuf)
597{
598 return gst_mini_object_replace ((GstMiniObject **) obuf, (GstMiniObject *) nbuf);
599}
600
601/* creating a region */
602
603GST_API
604GstBuffer* gst_buffer_copy_region (GstBuffer *parent, GstBufferCopyFlags flags,
605 gsize offset, gsize size);
606
607/* append two buffers */
608
609GST_API
610GstBuffer* gst_buffer_append_region (GstBuffer *buf1, GstBuffer *buf2,
611 gssize offset, gssize size);
612GST_API
613GstBuffer* gst_buffer_append (GstBuffer *buf1, GstBuffer *buf2);
614
615/* metadata */
616#include <gst/gstmeta.h>
617
618/**
619 * GstBufferForeachMetaFunc:
620 * @buffer: a #GstBuffer
621 * @meta: (out) (nullable): a pointer to a #GstMeta
622 * @user_data: user data passed to gst_buffer_foreach_meta()
623 *
624 * A function that will be called from gst_buffer_foreach_meta(). The @meta
625 * field will point to a the reference of the meta.
626 *
627 * @buffer should not be modified from this callback.
628 *
629 * When this function returns %TRUE, the next meta will be
630 * returned. When %FALSE is returned, gst_buffer_foreach_meta() will return.
631 *
632 * When @meta is set to %NULL, the item will be removed from the buffer.
633 *
634 * Returns: %FALSE when gst_buffer_foreach_meta() should stop
635 */
636typedef gboolean (*GstBufferForeachMetaFunc) (GstBuffer *buffer, GstMeta **meta,
637 gpointer user_data);
638
639GST_API
640GstMeta * gst_buffer_get_meta (GstBuffer *buffer, GType api);
641
642GST_API
643guint gst_buffer_get_n_meta (GstBuffer *buffer, GType api_type);
644
645GST_API
646GstMeta * gst_buffer_add_meta (GstBuffer *buffer, const GstMetaInfo *info,
647 gpointer params);
648GST_API
649gboolean gst_buffer_remove_meta (GstBuffer *buffer, GstMeta *meta);
650
651GST_API
652GstMeta * gst_buffer_iterate_meta (GstBuffer *buffer, gpointer *state);
653
654GST_API
655GstMeta * gst_buffer_iterate_meta_filtered (GstBuffer * buffer,
656 gpointer * state,
657 GType meta_api_type);
658GST_API
659gboolean gst_buffer_foreach_meta (GstBuffer *buffer,
660 GstBufferForeachMetaFunc func,
661 gpointer user_data);
662
663/**
664 * gst_value_set_buffer:
665 * @v: a #GValue to receive the data
666 * @b: (transfer none): a #GstBuffer to assign to the GstValue
667 *
668 * Sets @b as the value of @v. Caller retains reference to buffer.
669 */
670#define gst_value_set_buffer(v,b) g_value_set_boxed((v),(b))
671/**
672 * gst_value_take_buffer:
673 * @v: a #GValue to receive the data
674 * @b: (transfer full): a #GstBuffer to assign to the GstValue
675 *
676 * Sets @b as the value of @v. Caller gives away reference to buffer.
677 */
678#define gst_value_take_buffer(v,b) g_value_take_boxed(v,(b))
679/**
680 * gst_value_get_buffer:
681 * @v: a #GValue to query
682 *
683 * Receives a #GstBuffer as the value of @v. Does not return a reference to
684 * the buffer, so the pointer is only valid for as long as the caller owns
685 * a reference to @v.
686 *
687 * Returns: (transfer none): buffer
688 */
689#define gst_value_get_buffer(v) GST_BUFFER_CAST (g_value_get_boxed(v))
690
691typedef struct _GstParentBufferMeta GstParentBufferMeta;
692
693/**
694 * GstParentBufferMeta:
695 * @parent: the parent #GstMeta structure
696 * @buffer: the #GstBuffer on which a reference is being held.
697 *
698 * The #GstParentBufferMeta is a #GstMeta which can be attached to a #GstBuffer
699 * to hold a reference to another buffer that is only released when the child
700 * #GstBuffer is released.
701 *
702 * Typically, #GstParentBufferMeta is used when the child buffer is directly
703 * using the #GstMemory of the parent buffer, and wants to prevent the parent
704 * buffer from being returned to a buffer pool until the #GstMemory is available
705 * for re-use.
706 *
707 * Since: 1.6
708 */
709struct _GstParentBufferMeta
710{
711 GstMeta parent;
712
713 /*< public >*/
714 GstBuffer *buffer;
715};
716
717GST_API
718GType gst_parent_buffer_meta_api_get_type (void);
719#ifndef GST_DISABLE_DEPRECATED
720#define GST_TYPE_PARENT_BUFFER_META_API_TYPE GST_PARENT_BUFFER_META_API_TYPE
721#endif
722#define GST_PARENT_BUFFER_META_API_TYPE (gst_parent_buffer_meta_api_get_type())
723
724/**
725 * gst_buffer_get_parent_buffer_meta:
726 * @b: a #GstBuffer
727 *
728 * Find and return a #GstParentBufferMeta if one exists on the
729 * buffer
730 */
731#define gst_buffer_get_parent_buffer_meta(b) \
732 ((GstParentBufferMeta*)gst_buffer_get_meta((b),GST_PARENT_BUFFER_META_API_TYPE))
733
734GST_API
735const GstMetaInfo *gst_parent_buffer_meta_get_info (void);
736#define GST_PARENT_BUFFER_META_INFO (gst_parent_buffer_meta_get_info())
737
738/* implementation */
739
740GST_API
741GstParentBufferMeta *gst_buffer_add_parent_buffer_meta (GstBuffer *buffer,
742 GstBuffer *ref);
743
744typedef struct _GstReferenceTimestampMeta GstReferenceTimestampMeta;
745
746/**
747 * GstReferenceTimestampMeta:
748 * @parent: the parent #GstMeta structure
749 * @reference: identifier for the timestamp reference.
750 * @timestamp: timestamp
751 * @duration: duration, or %GST_CLOCK_TIME_NONE
752 *
753 * #GstReferenceTimestampMeta can be used to attach alternative timestamps and
754 * possibly durations to a #GstBuffer. These are generally not according to
755 * the pipeline clock and could be e.g. the NTP timestamp when the media was
756 * captured.
757 *
758 * The reference is stored as a #GstCaps in @reference. Examples of valid
759 * references would be "timestamp/x-drivername-stream" for timestamps that are locally
760 * generated by some driver named "drivername" when generating the stream,
761 * e.g. based on a frame counter, or "timestamp/x-ntp, host=pool.ntp.org,
762 * port=123" for timestamps based on a specific NTP server.
763 *
764 * Since: 1.14
765 */
766struct _GstReferenceTimestampMeta
767{
768 GstMeta parent;
769
770 /*< public >*/
771 GstCaps *reference;
772 GstClockTime timestamp, duration;
773};
774
775GST_API
776GType gst_reference_timestamp_meta_api_get_type (void);
777#define GST_REFERENCE_TIMESTAMP_META_API_TYPE (gst_reference_timestamp_meta_api_get_type())
778
779GST_API
780const GstMetaInfo *gst_reference_timestamp_meta_get_info (void);
781#define GST_REFERENCE_TIMESTAMP_META_INFO (gst_reference_timestamp_meta_get_info())
782
783/* implementation */
784
785GST_API
786GstReferenceTimestampMeta * gst_buffer_add_reference_timestamp_meta (GstBuffer * buffer,
787 GstCaps * reference,
788 GstClockTime timestamp,
789 GstClockTime duration);
790
791GST_API
792GstReferenceTimestampMeta * gst_buffer_get_reference_timestamp_meta (GstBuffer * buffer,
793 GstCaps * reference);
794
795#ifdef G_DEFINE_AUTOPTR_CLEANUP_FUNC
796G_DEFINE_AUTOPTR_CLEANUP_FUNC(GstBuffer, gst_buffer_unref)
797#endif
798
799#ifdef G_DEFINE_AUTOPTR_CLEANUP_FUNC
800G_DEFINE_AUTOPTR_CLEANUP_FUNC(GstBufferPool, gst_object_unref)
801#endif
802
803G_END_DECLS
804
805#endif /* __GST_BUFFER_H__ */
806