2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wtay@chello.be>
5 * gstbuffer.h: Header for GstBuffer object
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., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
24 #ifndef __GST_BUFFER_H__
25 #define __GST_BUFFER_H__
27 #include <gst/gstminiobject.h>
28 #include <gst/gstclock.h>
29 #include <gst/gstcaps.h>
30 #include <gst/gstmemory.h>
34 extern GType _gst_buffer_type;
36 typedef struct _GstBuffer GstBuffer;
37 typedef struct _GstBufferPool GstBufferPool;
40 * GST_BUFFER_TRACE_NAME:
42 * The name used for tracing memory allocations.
44 #define GST_BUFFER_TRACE_NAME "GstBuffer"
46 #define GST_TYPE_BUFFER (_gst_buffer_type)
47 #define GST_IS_BUFFER(obj) (GST_IS_MINI_OBJECT_TYPE(obj, GST_TYPE_BUFFER))
48 #define GST_BUFFER_CAST(obj) ((GstBuffer *)(obj))
49 #define GST_BUFFER(obj) (GST_BUFFER_CAST(obj))
55 * A flags word containing #GstBufferFlag flags set on this buffer.
57 #define GST_BUFFER_FLAGS(buf) GST_MINI_OBJECT_FLAGS(buf)
59 * GST_BUFFER_FLAG_IS_SET:
61 * @flag: the #GstBufferFlag to check.
63 * Gives the status of a specific flag on a buffer.
65 #define GST_BUFFER_FLAG_IS_SET(buf,flag) GST_MINI_OBJECT_FLAG_IS_SET (buf, flag)
67 * GST_BUFFER_FLAG_SET:
69 * @flag: the #GstBufferFlag to set.
71 * Sets a buffer flag on a buffer.
73 #define GST_BUFFER_FLAG_SET(buf,flag) GST_MINI_OBJECT_FLAG_SET (buf, flag)
75 * GST_BUFFER_FLAG_UNSET:
77 * @flag: the #GstBufferFlag to clear.
79 * Clears a buffer flag.
81 #define GST_BUFFER_FLAG_UNSET(buf,flag) GST_MINI_OBJECT_FLAG_UNSET (buf, flag)
87 * A pointer to the data element of this buffer.
89 #define GST_BUFFER_DATA(buf) (GST_BUFFER_CAST(buf)->data)
94 * The size in bytes of the data in this buffer.
96 #define GST_BUFFER_SIZE(buf) (GST_BUFFER_CAST(buf)->size)
98 * GST_BUFFER_TIMESTAMP:
99 * @buf: a #GstBuffer.:
101 * The timestamp in nanoseconds (as a #GstClockTime) of the data in the buffer.
102 * Value will be %GST_CLOCK_TIME_NONE if the timestamp is unknown.
105 #define GST_BUFFER_TIMESTAMP(buf) (GST_BUFFER_CAST(buf)->timestamp)
107 * GST_BUFFER_DURATION:
108 * @buf: a #GstBuffer.
110 * The duration in nanoseconds (as a #GstClockTime) of the data in the buffer.
111 * Value will be %GST_CLOCK_TIME_NONE if the duration is unknown.
113 #define GST_BUFFER_DURATION(buf) (GST_BUFFER_CAST(buf)->duration)
116 * @buf: a #GstBuffer.
118 * The caps for this buffer.
120 #define GST_BUFFER_CAPS(buf) (GST_BUFFER_CAST(buf)->caps)
123 * @buf: a #GstBuffer.
125 * The offset in the source file of the beginning of this buffer.
127 #define GST_BUFFER_OFFSET(buf) (GST_BUFFER_CAST(buf)->offset)
129 * GST_BUFFER_OFFSET_END:
130 * @buf: a #GstBuffer.
132 * The offset in the source file of the end of this buffer.
134 #define GST_BUFFER_OFFSET_END(buf) (GST_BUFFER_CAST(buf)->offset_end)
136 * GST_BUFFER_MALLOCDATA:
137 * @buf: a #GstBuffer.
139 * A pointer to any data allocated for this buffer using g_malloc(). If this is
140 * non-NULL, this memory will be freed at the end of the buffer's lifecycle
141 * (i.e. when its refcount becomes zero).
143 #define GST_BUFFER_MALLOCDATA(buf) (GST_BUFFER_CAST(buf)->malloc_data)
145 * GST_BUFFER_FREE_FUNC:
146 * @buf: a #GstBuffer.
148 * A pointer to a function that will be called on the buffer's malloc_data when
149 * this buffer is finalized. Defaults to g_free().
151 * Note that the free function only affects the buffer's malloc_data; if the
152 * buffer's malloc_data is %NULL, the function will not be called.
156 #define GST_BUFFER_FREE_FUNC(buf) (GST_BUFFER_CAST(buf)->free_func)
159 * GST_BUFFER_OFFSET_NONE:
161 * Constant for no-offset return results.
163 #define GST_BUFFER_OFFSET_NONE ((guint64)-1)
166 * GST_BUFFER_DURATION_IS_VALID:
167 * @buffer: a #GstBuffer
169 * Tests if the duration is known.
171 #define GST_BUFFER_DURATION_IS_VALID(buffer) (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_DURATION (buffer)))
173 * GST_BUFFER_TIMESTAMP_IS_VALID:
174 * @buffer: a #GstBuffer
176 * Tests if the timestamp is known.
178 #define GST_BUFFER_TIMESTAMP_IS_VALID(buffer) (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_TIMESTAMP (buffer)))
180 * GST_BUFFER_OFFSET_IS_VALID:
181 * @buffer: a #GstBuffer
183 * Tests if the start offset is known.
185 #define GST_BUFFER_OFFSET_IS_VALID(buffer) (GST_BUFFER_OFFSET (buffer) != GST_BUFFER_OFFSET_NONE)
187 * GST_BUFFER_OFFSET_END_IS_VALID:
188 * @buffer: a #GstBuffer
190 * Tests if the end offset is known.
192 #define GST_BUFFER_OFFSET_END_IS_VALID(buffer) (GST_BUFFER_OFFSET_END (buffer) != GST_BUFFER_OFFSET_NONE)
194 * GST_BUFFER_IS_DISCONT:
195 * @buffer: a #GstBuffer
197 * Tests if the buffer marks a discontinuity in the stream.
201 #define GST_BUFFER_IS_DISCONT(buffer) (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_DISCONT))
205 * @GST_BUFFER_FLAG_READONLY: the buffer is read-only. This means the data of
206 * the buffer should not be modified. The metadata might still be modified.
207 * @GST_BUFFER_FLAG_PREROLL: the buffer is part of a preroll and should not be
209 * @GST_BUFFER_FLAG_DISCONT: the buffer marks a discontinuity in the stream.
210 * This typically occurs after a seek or a dropped buffer from a live or
212 * @GST_BUFFER_FLAG_IN_CAPS: the buffer has been added as a field in a #GstCaps.
213 * @GST_BUFFER_FLAG_GAP: the buffer has been created to fill a gap in the
214 * stream and contains media neutral data (elements can switch to optimized code
215 * path that ignores the buffer content).
216 * @GST_BUFFER_FLAG_DELTA_UNIT: this unit cannot be decoded independently.
217 * @GST_BUFFER_FLAG_MEDIA1: a flag whose use is specific to the caps of the buffer. Since: 0.10.23.
218 * @GST_BUFFER_FLAG_MEDIA2: a flag whose use is specific to the caps of the buffer. Since: 0.10.23.
219 * @GST_BUFFER_FLAG_MEDIA3: a flag whose use is specific to the caps of the buffer. Since: 0.10.23.
220 * @GST_BUFFER_FLAG_MEDIA4: a flag whose use is specific to the caps of the buffer. Since: 0.10.33.
221 * @GST_BUFFER_FLAG_LAST: additional flags can be added starting from this flag.
223 * A set of buffer flags used to describe properties of a #GstBuffer.
226 GST_BUFFER_FLAG_READONLY = GST_MINI_OBJECT_FLAG_READONLY,
227 GST_BUFFER_FLAG_PREROLL = (GST_MINI_OBJECT_FLAG_LAST << 0),
228 GST_BUFFER_FLAG_DISCONT = (GST_MINI_OBJECT_FLAG_LAST << 1),
229 GST_BUFFER_FLAG_IN_CAPS = (GST_MINI_OBJECT_FLAG_LAST << 2),
230 GST_BUFFER_FLAG_GAP = (GST_MINI_OBJECT_FLAG_LAST << 3),
231 GST_BUFFER_FLAG_DELTA_UNIT = (GST_MINI_OBJECT_FLAG_LAST << 4),
232 GST_BUFFER_FLAG_MEDIA1 = (GST_MINI_OBJECT_FLAG_LAST << 5),
233 GST_BUFFER_FLAG_MEDIA2 = (GST_MINI_OBJECT_FLAG_LAST << 6),
234 GST_BUFFER_FLAG_MEDIA3 = (GST_MINI_OBJECT_FLAG_LAST << 7),
235 GST_BUFFER_FLAG_MEDIA4 = (GST_MINI_OBJECT_FLAG_LAST << 8),
236 GST_BUFFER_FLAG_LAST = (GST_MINI_OBJECT_FLAG_LAST << 16)
241 * @mini_object: the parent structure
242 * @data: pointer to the buffer data
243 * @size: size of buffer data
244 * @timestamp: timestamp of the buffer, can be #GST_CLOCK_TIME_NONE when the
245 * timestamp is not known or relevant.
246 * @duration: duration in time of the buffer data, can be #GST_CLOCK_TIME_NONE
247 * when the duration is not known or relevant.
248 * @caps: the #GstCaps describing the data format in this buffer
249 * @offset: a media specific offset for the buffer data.
250 * For video frames, this is the frame number of this buffer.
251 * For audio samples, this is the offset of the first sample in this buffer.
252 * For file data or compressed data this is the byte offset of the first
253 * byte in this buffer.
254 * @offset_end: the last offset contained in this buffer. It has the same
256 * @malloc_data: a pointer to the allocated memory associated with this buffer.
257 * When the buffer is freed, this data will freed with @free_func.
258 * @free_func: a custom function that will be called with @malloc_data, defaults
259 * to g_free(). Since 0.10.22.
260 * @parent: the parent buffer if this is a subbuffer. Since 0.10.26.
262 * The structure of a #GstBuffer. Use the associated macros to access the public
266 GstMiniObject mini_object;
268 /*< public >*/ /* with COW */
271 GstClockTime timestamp;
272 GstClockTime duration;
274 /* the media type of this buffer */
277 /* media specific offset */
281 /* pointer to data and its size, backwards compatibility */
284 guint8 *bw_malloc_data;
285 GFreeFunc bw_free_func;
287 /* pointer to memory blocks */
295 GstBuffer * gst_buffer_new (void);
296 GstBuffer * gst_buffer_new_and_alloc (guint size);
297 GstBuffer * gst_buffer_try_new_and_alloc (guint size);
300 guint gst_buffer_n_memory (GstBuffer *buffer);
301 void gst_buffer_take_memory (GstBuffer *buffer, GstMemory *mem);
302 GstMemory * gst_buffer_peek_memory (GstBuffer *buffer, guint idx);
303 void gst_buffer_remove_memory (GstBuffer *buffer, guint idx);
305 gsize gst_buffer_get_memory_size (GstBuffer *buffer);
308 gpointer gst_buffer_map (GstBuffer *buffer, gsize *size, gsize *maxsize,
310 gboolean gst_buffer_unmap (GstBuffer *buffer, gpointer data, gsize size);
313 * gst_buffer_set_data:
315 * @data: The data (a #guint8 *) to set on the buffer.
316 * @size: The size (in bytes, as a #guint) of the data being set.
318 * A convenience function to set the data and size on a buffer.
319 * This will replace any existing data pointer set on this buffer, but will
320 * not change GST_BUFFER_MALLOCDATA(), if any. Callers should ensure that
321 * GST_BUFFER_MALLOCDATA() is non-NULL, or should free that and set it to NULL.
323 * No checks are done on the data or size arguments passed.
325 #define gst_buffer_set_data(buf, data, size) \
327 GST_BUFFER_DATA (buf) = data; \
328 GST_BUFFER_SIZE (buf) = size; \
334 * @buf: a #GstBuffer.
336 * Increases the refcount of the given buffer by one.
338 * Note that the refcount affects the writeability
339 * of @buf and its metadata, see gst_buffer_is_writable() and
340 * gst_buffer_is_metadata_writable(). It is
341 * important to note that keeping additional references to
342 * GstBuffer instances can potentially increase the number
343 * of memcpy operations in a pipeline.
345 * Returns: (transfer full): @buf
347 #ifdef _FOOL_GTK_DOC_
348 G_INLINE_FUNC GstBuffer * gst_buffer_ref (GstBuffer * buf);
351 static inline GstBuffer *
352 gst_buffer_ref (GstBuffer * buf)
354 return (GstBuffer *) gst_mini_object_ref (GST_MINI_OBJECT_CAST (buf));
359 * @buf: (transfer full): a #GstBuffer.
361 * Decreases the refcount of the buffer. If the refcount reaches 0, the buffer
362 * will be freed. If GST_BUFFER_MALLOCDATA() is non-NULL, this pointer will
363 * also be freed at this time.
365 #ifdef _FOOL_GTK_DOC_
366 G_INLINE_FUNC void gst_buffer_unref (GstBuffer * buf);
370 gst_buffer_unref (GstBuffer * buf)
372 gst_mini_object_unref (GST_MINI_OBJECT_CAST (buf));
378 * @buf: a #GstBuffer.
380 * Create a copy of the given buffer. This will also make a newly allocated
381 * copy of the data the source buffer contains.
383 * Returns: (transfer full): a new copy of @buf.
385 #ifdef _FOOL_GTK_DOC_
386 G_INLINE_FUNC GstBuffer * gst_buffer_copy (const GstBuffer * buf);
389 static inline GstBuffer *
390 gst_buffer_copy (const GstBuffer * buf)
392 return GST_BUFFER (gst_mini_object_copy (GST_MINI_OBJECT_CONST_CAST (buf)));
397 * GstBufferCopyFlags:
398 * @GST_BUFFER_COPY_FLAGS: flag indicating that buffer flags should be copied
399 * @GST_BUFFER_COPY_TIMESTAMPS: flag indicating that buffer timestamp, duration,
400 * offset and offset_end should be copied
401 * @GST_BUFFER_COPY_CAPS: flag indicating that buffer caps should be copied
403 * A set of flags that can be provided to the gst_buffer_copy_metadata()
404 * function to specify which metadata fields should be copied.
409 GST_BUFFER_COPY_FLAGS = (1 << 0),
410 GST_BUFFER_COPY_TIMESTAMPS = (1 << 1),
411 GST_BUFFER_COPY_CAPS = (1 << 2)
412 } GstBufferCopyFlags;
415 * GST_BUFFER_COPY_ALL:
417 * Combination of all possible fields that can be copied with
418 * gst_buffer_copy_metadata().
422 #define GST_BUFFER_COPY_ALL (GST_BUFFER_COPY_FLAGS | GST_BUFFER_COPY_TIMESTAMPS | GST_BUFFER_COPY_CAPS)
424 /* copies memory or metadata into newly allocated buffer */
425 void gst_buffer_copy_memory (GstBuffer *dest, GstBuffer *src,
426 gsize offset, gsize size, gboolean merge);
427 void gst_buffer_share_memory (GstBuffer *dest, GstBuffer *src);
428 void gst_buffer_copy_metadata (GstBuffer *dest, GstBuffer *src,
429 GstBufferCopyFlags flags);
432 * gst_buffer_is_writable:
435 * Tests if you can safely write data into a buffer's data array or validly
436 * modify the caps and timestamp metadata. Metadata in a GstBuffer is always
437 * writable, but it is only safe to change it when there is only one owner
438 * of the buffer - ie, the refcount is 1.
440 #define gst_buffer_is_writable(buf) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (buf))
442 * gst_buffer_make_writable:
443 * @buf: (transfer full): a #GstBuffer
445 * Makes a writable buffer from the given buffer. If the source buffer is
446 * already writable, this will simply return the same buffer. A copy will
447 * otherwise be made using gst_buffer_copy().
449 * Returns: (transfer full): a writable buffer which may or may not be the
452 #define gst_buffer_make_writable(buf) GST_BUFFER_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (buf)))
454 /* Ensure that the metadata of the buffer is writable, even if the buffer data
456 gboolean gst_buffer_is_metadata_writable (GstBuffer *buf);
457 GstBuffer* gst_buffer_make_metadata_writable (GstBuffer *buf);
460 * gst_buffer_replace:
461 * @obuf: (inout) (transfer full): pointer to a pointer to a #GstBuffer to be
463 * @nbuf: (transfer none) (allow-none): pointer to a #GstBuffer that will
464 * replace the buffer pointed to by @obuf.
466 * Modifies a pointer to a #GstBuffer to point to a different #GstBuffer. The
467 * modification is done atomically (so this is useful for ensuring thread safety
468 * in some cases), and the reference counts are updated appropriately (the old
469 * buffer is unreffed, the new is reffed).
471 * Either @nbuf or the #GstBuffer pointed to by @obuf may be NULL.
473 #define gst_buffer_replace(obuf,nbuf) \
475 GstBuffer **___obufaddr = (GstBuffer **)(obuf); \
476 gst_mini_object_replace ((GstMiniObject **)___obufaddr, \
477 GST_MINI_OBJECT_CAST (nbuf)); \
480 GstCaps* gst_buffer_get_caps (GstBuffer *buffer);
481 void gst_buffer_set_caps (GstBuffer *buffer, GstCaps *caps);
483 /* creating a subbuffer */
484 GstBuffer* gst_buffer_create_sub (GstBuffer *parent, guint offset, guint size);
486 /* span, two buffers, intelligently */
487 gboolean gst_buffer_is_span_fast (GstBuffer *buf1, GstBuffer *buf2);
488 GstBuffer* gst_buffer_span (GstBuffer *buf1, guint32 offset, GstBuffer *buf2, guint32 len);
491 #include <gst/gstmeta.h>
493 GstMeta * gst_buffer_get_meta (GstBuffer *buffer, const GstMetaInfo *info);
494 GstMeta * gst_buffer_add_meta (GstBuffer *buffer, const GstMetaInfo *info,
496 gboolean gst_buffer_remove_meta (GstBuffer *buffer, GstMeta *meta);
498 GstMeta * gst_buffer_iterate_meta (GstBuffer *buffer, gpointer *state);
501 * gst_value_set_buffer:
502 * @v: a #GValue to receive the data
503 * @b: (transfer none): a #GstBuffer to assign to the GstValue
505 * Sets @b as the value of @v. Caller retains reference to buffer.
507 #define gst_value_set_buffer(v,b) g_value_set_boxed((v),(b))
509 * gst_value_take_buffer:
510 * @v: a #GValue to receive the data
511 * @b: (transfer full): a #GstBuffer to assign to the GstValue
513 * Sets @b as the value of @v. Caller gives away reference to buffer.
515 #define gst_value_take_buffer(v,b) g_value_take_boxed(v,(b))
517 * gst_value_get_buffer:
518 * @v: a #GValue to query
520 * Receives a #GstBuffer as the value of @v. Does not return a reference to
521 * the buffer, so the pointer is only valid for as long as the caller owns
524 * Returns: (transfer none): buffer
526 #define gst_value_get_buffer(v) GST_BUFFER_CAST (g_value_get_boxed(v))
530 #endif /* __GST_BUFFER_H__ */