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