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>
33 extern GType _gst_buffer_type;
35 typedef struct _GstBuffer GstBuffer;
36 typedef struct _GstBufferPool GstBufferPool;
39 * GST_BUFFER_TRACE_NAME:
41 * The name used for tracing memory allocations.
43 #define GST_BUFFER_TRACE_NAME "GstBuffer"
45 #define GST_TYPE_BUFFER (_gst_buffer_type)
46 #define GST_IS_BUFFER(obj) (GST_IS_MINI_OBJECT_TYPE(obj, GST_TYPE_BUFFER))
47 #define GST_BUFFER_CAST(obj) ((GstBuffer *)(obj))
48 #define GST_BUFFER(obj) (GST_BUFFER_CAST(obj))
54 * A flags word containing #GstBufferFlag flags set on this buffer.
56 #define GST_BUFFER_FLAGS(buf) GST_MINI_OBJECT_FLAGS(buf)
58 * GST_BUFFER_FLAG_IS_SET:
60 * @flag: the #GstBufferFlag to check.
62 * Gives the status of a specific flag on a buffer.
64 #define GST_BUFFER_FLAG_IS_SET(buf,flag) GST_MINI_OBJECT_FLAG_IS_SET (buf, flag)
66 * GST_BUFFER_FLAG_SET:
68 * @flag: the #GstBufferFlag to set.
70 * Sets a buffer flag on a buffer.
72 #define GST_BUFFER_FLAG_SET(buf,flag) GST_MINI_OBJECT_FLAG_SET (buf, flag)
74 * GST_BUFFER_FLAG_UNSET:
76 * @flag: the #GstBufferFlag to clear.
78 * Clears a buffer flag.
80 #define GST_BUFFER_FLAG_UNSET(buf,flag) GST_MINI_OBJECT_FLAG_UNSET (buf, flag)
86 * A pointer to the data element of this buffer.
88 #define GST_BUFFER_DATA(buf) (GST_BUFFER_CAST(buf)->data)
93 * The size in bytes of the data in this buffer.
95 #define GST_BUFFER_SIZE(buf) (GST_BUFFER_CAST(buf)->size)
97 * GST_BUFFER_TIMESTAMP:
98 * @buf: a #GstBuffer.:
100 * The timestamp in nanoseconds (as a #GstClockTime) of the data in the buffer.
101 * Value will be %GST_CLOCK_TIME_NONE if the timestamp is unknown.
104 #define GST_BUFFER_TIMESTAMP(buf) (GST_BUFFER_CAST(buf)->timestamp)
106 * GST_BUFFER_DURATION:
107 * @buf: a #GstBuffer.
109 * The duration in nanoseconds (as a #GstClockTime) of the data in the buffer.
110 * Value will be %GST_CLOCK_TIME_NONE if the duration is unknown.
112 #define GST_BUFFER_DURATION(buf) (GST_BUFFER_CAST(buf)->duration)
115 * @buf: a #GstBuffer.
117 * The caps for this buffer.
119 #define GST_BUFFER_CAPS(buf) (GST_BUFFER_CAST(buf)->caps)
122 * @buf: a #GstBuffer.
124 * The offset in the source file of the beginning of this buffer.
126 #define GST_BUFFER_OFFSET(buf) (GST_BUFFER_CAST(buf)->offset)
128 * GST_BUFFER_OFFSET_END:
129 * @buf: a #GstBuffer.
131 * The offset in the source file of the end of this buffer.
133 #define GST_BUFFER_OFFSET_END(buf) (GST_BUFFER_CAST(buf)->offset_end)
135 * GST_BUFFER_MALLOCDATA:
136 * @buf: a #GstBuffer.
138 * A pointer to any data allocated for this buffer using g_malloc(). If this is
139 * non-NULL, this memory will be freed at the end of the buffer's lifecycle
140 * (i.e. when its refcount becomes zero).
142 #define GST_BUFFER_MALLOCDATA(buf) (GST_BUFFER_CAST(buf)->malloc_data)
144 * GST_BUFFER_FREE_FUNC:
145 * @buf: a #GstBuffer.
147 * A pointer to a function that will be called on the buffer's malloc_data when
148 * this buffer is finalized. Defaults to g_free().
150 * Note that the free function only affects the buffer's malloc_data; if the
151 * buffer's malloc_data is %NULL, the function will not be called.
155 #define GST_BUFFER_FREE_FUNC(buf) (GST_BUFFER_CAST(buf)->free_func)
158 * GST_BUFFER_OFFSET_NONE:
160 * Constant for no-offset return results.
162 #define GST_BUFFER_OFFSET_NONE ((guint64)-1)
165 * GST_BUFFER_DURATION_IS_VALID:
166 * @buffer: a #GstBuffer
168 * Tests if the duration is known.
170 #define GST_BUFFER_DURATION_IS_VALID(buffer) (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_DURATION (buffer)))
172 * GST_BUFFER_TIMESTAMP_IS_VALID:
173 * @buffer: a #GstBuffer
175 * Tests if the timestamp is known.
177 #define GST_BUFFER_TIMESTAMP_IS_VALID(buffer) (GST_CLOCK_TIME_IS_VALID (GST_BUFFER_TIMESTAMP (buffer)))
179 * GST_BUFFER_OFFSET_IS_VALID:
180 * @buffer: a #GstBuffer
182 * Tests if the start offset is known.
184 #define GST_BUFFER_OFFSET_IS_VALID(buffer) (GST_BUFFER_OFFSET (buffer) != GST_BUFFER_OFFSET_NONE)
186 * GST_BUFFER_OFFSET_END_IS_VALID:
187 * @buffer: a #GstBuffer
189 * Tests if the end offset is known.
191 #define GST_BUFFER_OFFSET_END_IS_VALID(buffer) (GST_BUFFER_OFFSET_END (buffer) != GST_BUFFER_OFFSET_NONE)
193 * GST_BUFFER_IS_DISCONT:
194 * @buffer: a #GstBuffer
196 * Tests if the buffer marks a discontinuity in the stream.
200 #define GST_BUFFER_IS_DISCONT(buffer) (GST_BUFFER_FLAG_IS_SET (buffer, GST_BUFFER_FLAG_DISCONT))
204 * @GST_BUFFER_FLAG_READONLY: the buffer is read-only. This means the data of
205 * the buffer should not be modified. The metadata might still be modified.
206 * @GST_BUFFER_FLAG_PREROLL: the buffer is part of a preroll and should not be
208 * @GST_BUFFER_FLAG_DISCONT: the buffer marks a discontinuity in the stream.
209 * This typically occurs after a seek or a dropped buffer from a live or
211 * @GST_BUFFER_FLAG_IN_CAPS: the buffer has been added as a field in a #GstCaps.
212 * @GST_BUFFER_FLAG_GAP: the buffer has been created to fill a gap in the
213 * stream and contains media neutral data (elements can switch to optimized code
214 * path that ignores the buffer content).
215 * @GST_BUFFER_FLAG_DELTA_UNIT: this unit cannot be decoded independently.
216 * @GST_BUFFER_FLAG_MEDIA1: a flag whose use is specific to the caps of the buffer. Since: 0.10.23.
217 * @GST_BUFFER_FLAG_MEDIA2: a flag whose use is specific to the caps of the buffer. Since: 0.10.23.
218 * @GST_BUFFER_FLAG_MEDIA3: a flag whose use is specific to the caps of the buffer. Since: 0.10.23.
219 * @GST_BUFFER_FLAG_MEDIA4: a flag whose use is specific to the caps of the buffer. Since: 0.10.33.
220 * @GST_BUFFER_FLAG_LAST: additional flags can be added starting from this flag.
222 * A set of buffer flags used to describe properties of a #GstBuffer.
225 GST_BUFFER_FLAG_READONLY = GST_MINI_OBJECT_FLAG_READONLY,
226 GST_BUFFER_FLAG_PREROLL = (GST_MINI_OBJECT_FLAG_LAST << 0),
227 GST_BUFFER_FLAG_DISCONT = (GST_MINI_OBJECT_FLAG_LAST << 1),
228 GST_BUFFER_FLAG_IN_CAPS = (GST_MINI_OBJECT_FLAG_LAST << 2),
229 GST_BUFFER_FLAG_GAP = (GST_MINI_OBJECT_FLAG_LAST << 3),
230 GST_BUFFER_FLAG_DELTA_UNIT = (GST_MINI_OBJECT_FLAG_LAST << 4),
231 GST_BUFFER_FLAG_MEDIA1 = (GST_MINI_OBJECT_FLAG_LAST << 5),
232 GST_BUFFER_FLAG_MEDIA2 = (GST_MINI_OBJECT_FLAG_LAST << 6),
233 GST_BUFFER_FLAG_MEDIA3 = (GST_MINI_OBJECT_FLAG_LAST << 7),
234 GST_BUFFER_FLAG_MEDIA4 = (GST_MINI_OBJECT_FLAG_LAST << 8),
235 GST_BUFFER_FLAG_LAST = (GST_MINI_OBJECT_FLAG_LAST << 16)
240 * @mini_object: the parent structure
241 * @data: pointer to the buffer data
242 * @size: size of buffer data
243 * @timestamp: timestamp of the buffer, can be #GST_CLOCK_TIME_NONE when the
244 * timestamp is not known or relevant.
245 * @duration: duration in time of the buffer data, can be #GST_CLOCK_TIME_NONE
246 * when the duration is not known or relevant.
247 * @caps: the #GstCaps describing the data format in this buffer
248 * @offset: a media specific offset for the buffer data.
249 * For video frames, this is the frame number of this buffer.
250 * For audio samples, this is the offset of the first sample in this buffer.
251 * For file data or compressed data this is the byte offset of the first
252 * byte in this buffer.
253 * @offset_end: the last offset contained in this buffer. It has the same
255 * @malloc_data: a pointer to the allocated memory associated with this buffer.
256 * When the buffer is freed, this data will freed with @free_func.
257 * @free_func: a custom function that will be called with @malloc_data, defaults
258 * to g_free(). Since 0.10.22.
259 * @parent: the parent buffer if this is a subbuffer. Since 0.10.26.
261 * The structure of a #GstBuffer. Use the associated macros to access the public
265 GstMiniObject mini_object;
267 /*< public >*/ /* with COW */
268 /* pointer to data and its size */
273 GstClockTime timestamp;
274 GstClockTime duration;
276 /* the media type of this buffer */
279 /* media specific offset */
293 GstBuffer * gst_buffer_new (void);
294 GstBuffer * gst_buffer_new_and_alloc (guint size);
295 GstBuffer * gst_buffer_try_new_and_alloc (guint size);
298 * gst_buffer_set_data:
300 * @data: The data (a #guint8 *) to set on the buffer.
301 * @size: The size (in bytes, as a #guint) of the data being set.
303 * A convenience function to set the data and size on a buffer.
304 * This will replace any existing data pointer set on this buffer, but will
305 * not change GST_BUFFER_MALLOCDATA(), if any. Callers should ensure that
306 * GST_BUFFER_MALLOCDATA() is non-NULL, or should free that and set it to NULL.
308 * No checks are done on the data or size arguments passed.
310 #define gst_buffer_set_data(buf, data, size) \
312 GST_BUFFER_DATA (buf) = data; \
313 GST_BUFFER_SIZE (buf) = size; \
319 * @buf: a #GstBuffer.
321 * Increases the refcount of the given buffer by one.
323 * Note that the refcount affects the writeability
324 * of @buf and its metadata, see gst_buffer_is_writable() and
325 * gst_buffer_is_metadata_writable(). It is
326 * important to note that keeping additional references to
327 * GstBuffer instances can potentially increase the number
328 * of memcpy operations in a pipeline.
330 * Returns: (transfer full): @buf
332 #ifdef _FOOL_GTK_DOC_
333 G_INLINE_FUNC GstBuffer * gst_buffer_ref (GstBuffer * buf);
336 static inline GstBuffer *
337 gst_buffer_ref (GstBuffer * buf)
339 return (GstBuffer *) gst_mini_object_ref (GST_MINI_OBJECT_CAST (buf));
344 * @buf: (transfer full): a #GstBuffer.
346 * Decreases the refcount of the buffer. If the refcount reaches 0, the buffer
347 * will be freed. If GST_BUFFER_MALLOCDATA() is non-NULL, this pointer will
348 * also be freed at this time.
350 #ifdef _FOOL_GTK_DOC_
351 G_INLINE_FUNC void gst_buffer_unref (GstBuffer * buf);
355 gst_buffer_unref (GstBuffer * buf)
357 gst_mini_object_unref (GST_MINI_OBJECT_CAST (buf));
363 * @buf: a #GstBuffer.
365 * Create a copy of the given buffer. This will also make a newly allocated
366 * copy of the data the source buffer contains.
368 * Returns: (transfer full): a new copy of @buf.
370 #ifdef _FOOL_GTK_DOC_
371 G_INLINE_FUNC GstBuffer * gst_buffer_copy (const GstBuffer * buf);
374 static inline GstBuffer *
375 gst_buffer_copy (const GstBuffer * buf)
377 return GST_BUFFER (gst_mini_object_copy (GST_MINI_OBJECT_CONST_CAST (buf)));
382 * GstBufferCopyFlags:
383 * @GST_BUFFER_COPY_FLAGS: flag indicating that buffer flags should be copied
384 * @GST_BUFFER_COPY_TIMESTAMPS: flag indicating that buffer timestamp, duration,
385 * offset and offset_end should be copied
386 * @GST_BUFFER_COPY_CAPS: flag indicating that buffer caps should be copied
388 * A set of flags that can be provided to the gst_buffer_copy_metadata()
389 * function to specify which metadata fields should be copied.
394 GST_BUFFER_COPY_FLAGS = (1 << 0),
395 GST_BUFFER_COPY_TIMESTAMPS = (1 << 1),
396 GST_BUFFER_COPY_CAPS = (1 << 2)
397 } GstBufferCopyFlags;
400 * GST_BUFFER_COPY_ALL:
402 * Combination of all possible fields that can be copied with
403 * gst_buffer_copy_metadata().
407 #define GST_BUFFER_COPY_ALL (GST_BUFFER_COPY_FLAGS | GST_BUFFER_COPY_TIMESTAMPS | GST_BUFFER_COPY_CAPS)
409 /* copies metadata into newly allocated buffer */
410 void gst_buffer_copy_metadata (GstBuffer *dest, const GstBuffer *src,
411 GstBufferCopyFlags flags);
414 * gst_buffer_is_writable:
417 * Tests if you can safely write data into a buffer's data array or validly
418 * modify the caps and timestamp metadata. Metadata in a GstBuffer is always
419 * writable, but it is only safe to change it when there is only one owner
420 * of the buffer - ie, the refcount is 1.
422 #define gst_buffer_is_writable(buf) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (buf))
424 * gst_buffer_make_writable:
425 * @buf: (transfer full): a #GstBuffer
427 * Makes a writable buffer from the given buffer. If the source buffer is
428 * already writable, this will simply return the same buffer. A copy will
429 * otherwise be made using gst_buffer_copy().
431 * Returns: (transfer full): a writable buffer which may or may not be the
434 #define gst_buffer_make_writable(buf) GST_BUFFER_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (buf)))
436 /* Ensure that the metadata of the buffer is writable, even if the buffer data
438 gboolean gst_buffer_is_metadata_writable (GstBuffer *buf);
439 GstBuffer* gst_buffer_make_metadata_writable (GstBuffer *buf);
442 * gst_buffer_replace:
443 * @obuf: (inout) (transfer full): pointer to a pointer to a #GstBuffer to be
445 * @nbuf: (transfer none) (allow-none): pointer to a #GstBuffer that will
446 * replace the buffer pointed to by @obuf.
448 * Modifies a pointer to a #GstBuffer to point to a different #GstBuffer. The
449 * modification is done atomically (so this is useful for ensuring thread safety
450 * in some cases), and the reference counts are updated appropriately (the old
451 * buffer is unreffed, the new is reffed).
453 * Either @nbuf or the #GstBuffer pointed to by @obuf may be NULL.
455 #define gst_buffer_replace(obuf,nbuf) \
457 GstBuffer **___obufaddr = (GstBuffer **)(obuf); \
458 gst_mini_object_replace ((GstMiniObject **)___obufaddr, \
459 GST_MINI_OBJECT_CAST (nbuf)); \
462 GstCaps* gst_buffer_get_caps (GstBuffer *buffer);
463 void gst_buffer_set_caps (GstBuffer *buffer, GstCaps *caps);
465 /* creating a subbuffer */
466 GstBuffer* gst_buffer_create_sub (GstBuffer *parent, guint offset, guint size);
468 /* span, two buffers, intelligently */
469 gboolean gst_buffer_is_span_fast (GstBuffer *buf1, GstBuffer *buf2);
470 GstBuffer* gst_buffer_span (GstBuffer *buf1, guint32 offset, GstBuffer *buf2, guint32 len);
473 #include <gst/gstmeta.h>
475 GstMeta * gst_buffer_get_meta (GstBuffer *buffer, const GstMetaInfo *info);
476 GstMeta * gst_buffer_add_meta (GstBuffer *buffer, const GstMetaInfo *info,
478 gboolean gst_buffer_remove_meta (GstBuffer *buffer, GstMeta *meta);
480 GstMeta * gst_buffer_iterate_meta (GstBuffer *buffer, gpointer *state);
483 * gst_value_set_buffer:
484 * @v: a #GValue to receive the data
485 * @b: (transfer none): a #GstBuffer to assign to the GstValue
487 * Sets @b as the value of @v. Caller retains reference to buffer.
489 #define gst_value_set_buffer(v,b) g_value_set_boxed((v),(b))
491 * gst_value_take_buffer:
492 * @v: a #GValue to receive the data
493 * @b: (transfer full): a #GstBuffer to assign to the GstValue
495 * Sets @b as the value of @v. Caller gives away reference to buffer.
497 #define gst_value_take_buffer(v,b) g_value_take_boxed(v,(b))
499 * gst_value_get_buffer:
500 * @v: a #GValue to query
502 * Receives a #GstBuffer as the value of @v. Does not return a reference to
503 * the buffer, so the pointer is only valid for as long as the caller owns
506 * Returns: (transfer none): buffer
508 #define gst_value_get_buffer(v) GST_BUFFER_CAST (g_value_get_boxed(v))
512 #endif /* __GST_BUFFER_H__ */