mirror of
https://gitlab.freedesktop.org/gstreamer/gstreamer.git
synced 2024-10-03 17:22:29 +00:00
1171 lines
32 KiB
C
1171 lines
32 KiB
C
/* GStreamer
|
|
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
|
|
* 2000 Wim Taymans <wtay@chello.be>
|
|
*
|
|
* gstbuffer.c: Buffer operations
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Library General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2 of the License, or (at your option) any later version.
|
|
*
|
|
* This library is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
|
* Library General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Library General Public
|
|
* License along with this library; if not, write to the
|
|
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
|
* Boston, MA 02111-1307, USA.
|
|
*/
|
|
|
|
/**
|
|
* SECTION:gstbuffer
|
|
* @short_description: Data-passing buffer type, supporting sub-buffers.
|
|
* @see_also: #GstPad, #GstMiniObject
|
|
*
|
|
* Buffers are the basic unit of data transfer in GStreamer. The #GstBuffer
|
|
* type provides all the state necessary to define a region of memory as part
|
|
* of a stream. Sub-buffers are also supported, allowing a smaller region of a
|
|
* buffer to become its own buffer, with mechanisms in place to ensure that
|
|
* neither memory space goes away prematurely.
|
|
*
|
|
* Buffers are usually created with gst_buffer_new(). After a buffer has been
|
|
* created one will typically allocate memory for it and set the size of the
|
|
* buffer data. The following example creates a buffer that can hold a given
|
|
* video frame with a given width, height and bits per plane.
|
|
* <example>
|
|
* <title>Creating a buffer for a video frame</title>
|
|
* <programlisting>
|
|
* GstBuffer *buffer;
|
|
* gint size, width, height, bpp;
|
|
* ...
|
|
* size = width * height * bpp;
|
|
* buffer = gst_buffer_new ();
|
|
* GST_BUFFER_SIZE (buffer) = size;
|
|
* GST_BUFFER_MALLOCDATA (buffer) = g_malloc (size);
|
|
* GST_BUFFER_DATA (buffer) = GST_BUFFER_MALLOCDATA (buffer);
|
|
* ...
|
|
* </programlisting>
|
|
* </example>
|
|
*
|
|
* Alternatively, use gst_buffer_new_and_alloc()
|
|
* to create a buffer with preallocated data of a given size.
|
|
*
|
|
* The data pointed to by the buffer can be retrieved with the GST_BUFFER_DATA()
|
|
* macro. The size of the data can be found with GST_BUFFER_SIZE(). For buffers
|
|
* of size 0, the data pointer is undefined (usually NULL) and should never be used.
|
|
*
|
|
* If an element knows what pad you will push the buffer out on, it should use
|
|
* gst_pad_alloc_buffer() instead to create a buffer. This allows downstream
|
|
* elements to provide special buffers to write in, like hardware buffers.
|
|
*
|
|
* A buffer has a pointer to a #GstCaps describing the media type of the data
|
|
* in the buffer. Attach caps to the buffer with gst_buffer_set_caps(); this
|
|
* is typically done before pushing out a buffer using gst_pad_push() so that
|
|
* the downstream element knows the type of the buffer.
|
|
*
|
|
* A buffer will usually have a timestamp, and a duration, but neither of these
|
|
* are guaranteed (they may be set to #GST_CLOCK_TIME_NONE). Whenever a
|
|
* meaningful value can be given for these, they should be set. The timestamp
|
|
* and duration are measured in nanoseconds (they are #GstClockTime values).
|
|
*
|
|
* A buffer can also have one or both of a start and an end offset. These are
|
|
* media-type specific. For video buffers, the start offset will generally be
|
|
* the frame number. For audio buffers, it will be the number of samples
|
|
* produced so far. For compressed data, it could be the byte offset in a
|
|
* source or destination file. Likewise, the end offset will be the offset of
|
|
* the end of the buffer. These can only be meaningfully interpreted if you
|
|
* know the media type of the buffer (the #GstCaps set on it). Either or both
|
|
* can be set to #GST_BUFFER_OFFSET_NONE.
|
|
*
|
|
* gst_buffer_ref() is used to increase the refcount of a buffer. This must be
|
|
* done when you want to keep a handle to the buffer after pushing it to the
|
|
* next element.
|
|
*
|
|
* To efficiently create a smaller buffer out of an existing one, you can
|
|
* use gst_buffer_create_sub().
|
|
*
|
|
* If a plug-in wants to modify the buffer data in-place, it should first obtain
|
|
* a buffer that is safe to modify by using gst_buffer_make_writable(). This
|
|
* function is optimized so that a copy will only be made when it is necessary.
|
|
*
|
|
* A plugin that only wishes to modify the metadata of a buffer, such as the
|
|
* offset, timestamp or caps, should use gst_buffer_make_metadata_writable(),
|
|
* which will create a subbuffer of the original buffer to ensure the caller
|
|
* has sole ownership, and not copy the buffer data.
|
|
*
|
|
* Several flags of the buffer can be set and unset with the
|
|
* GST_BUFFER_FLAG_SET() and GST_BUFFER_FLAG_UNSET() macros. Use
|
|
* GST_BUFFER_FLAG_IS_SET() to test if a certain #GstBufferFlag is set.
|
|
*
|
|
* Buffers can be efficiently merged into a larger buffer with
|
|
* gst_buffer_merge() and gst_buffer_span() if the gst_buffer_is_span_fast()
|
|
* function returns TRUE.
|
|
*
|
|
* An element should either unref the buffer or push it out on a src pad
|
|
* using gst_pad_push() (see #GstPad).
|
|
*
|
|
* Buffers are usually freed by unreffing them with gst_buffer_unref(). When
|
|
* the refcount drops to 0, any data pointed to by GST_BUFFER_MALLOCDATA() will
|
|
* also be freed.
|
|
*
|
|
* Last reviewed on August 11th, 2006 (0.10.10)
|
|
*/
|
|
#include "gst_private.h"
|
|
|
|
#ifdef HAVE_UNISTD_H
|
|
#include <unistd.h>
|
|
#endif
|
|
#ifdef HAVE_STDLIB_H
|
|
#include <stdlib.h>
|
|
#endif
|
|
|
|
#include "gstbuffer.h"
|
|
#include "gstbufferpool.h"
|
|
#include "gstinfo.h"
|
|
#include "gstutils.h"
|
|
#include "gstminiobject.h"
|
|
#include "gstversion.h"
|
|
|
|
GType _gst_buffer_type = 0;
|
|
|
|
typedef struct _GstMetaItem GstMetaItem;
|
|
|
|
struct _GstMetaItem
|
|
{
|
|
GstMetaItem *next;
|
|
GstMeta meta;
|
|
};
|
|
|
|
#define GST_BUFFER_MEMORY(b) (((GstBufferImpl *)(b))->memory)
|
|
#define GST_BUFFER_META(b) (((GstBufferImpl *)(b))->item)
|
|
|
|
typedef struct
|
|
{
|
|
GstBuffer buffer;
|
|
|
|
GPtrArray *memory;
|
|
GstMetaItem *item;
|
|
} GstBufferImpl;
|
|
|
|
#define ITEM_SIZE(info) ((info)->size + sizeof (GstMetaItem))
|
|
|
|
/* buffer alignment in bytes
|
|
* an alignment of 8 would be the same as malloc() guarantees
|
|
*/
|
|
#ifdef HAVE_POSIX_MEMALIGN
|
|
#if defined(BUFFER_ALIGNMENT_MALLOC)
|
|
static size_t _gst_buffer_data_alignment = 8;
|
|
#elif defined(BUFFER_ALIGNMENT_PAGESIZE)
|
|
static size_t _gst_buffer_data_alignment = 0;
|
|
#elif defined(BUFFER_ALIGNMENT)
|
|
static size_t _gst_buffer_data_alignment = BUFFER_ALIGNMENT;
|
|
#else
|
|
#error "No buffer alignment configured"
|
|
#endif
|
|
#endif /* HAVE_POSIX_MEMALIGN */
|
|
|
|
void
|
|
_gst_buffer_initialize (void)
|
|
{
|
|
if (G_LIKELY (_gst_buffer_type == 0)) {
|
|
_gst_buffer_type = gst_mini_object_register ("GstBuffer");
|
|
#ifdef HAVE_GETPAGESIZE
|
|
#ifdef BUFFER_ALIGNMENT_PAGESIZE
|
|
_gst_buffer_data_alignment = getpagesize ();
|
|
#endif
|
|
#endif
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_copy_into:
|
|
* @dest: a destination #GstBuffer
|
|
* @src: a source #GstBuffer
|
|
* @flags: flags indicating what metadata fields should be copied.
|
|
* @offset: offset to copy from
|
|
* @size: total size to copy
|
|
*
|
|
* Copies the information from @src into @dest.
|
|
*
|
|
* @flags indicate which fields will be copied.
|
|
*/
|
|
void
|
|
gst_buffer_copy_into (GstBuffer * dest, GstBuffer * src,
|
|
GstBufferCopyFlags flags, gsize offset, gsize size)
|
|
{
|
|
GstMetaItem *walk;
|
|
gsize bufsize;
|
|
|
|
g_return_if_fail (dest != NULL);
|
|
g_return_if_fail (src != NULL);
|
|
|
|
/* nothing to copy if the buffers are the same */
|
|
if (G_UNLIKELY (dest == src))
|
|
return;
|
|
|
|
bufsize = gst_buffer_get_size (src);
|
|
if (size == -1)
|
|
size = bufsize - offset;
|
|
|
|
g_return_if_fail (bufsize >= offset + size);
|
|
g_return_if_fail (gst_buffer_is_writable (dest));
|
|
|
|
GST_CAT_LOG (GST_CAT_BUFFER, "copy %p to %p, offset %" G_GSIZE_FORMAT
|
|
"-%" G_GSIZE_FORMAT "/%" G_GSIZE_FORMAT, src, dest, offset, size,
|
|
bufsize);
|
|
|
|
if (flags & GST_BUFFER_COPY_FLAGS) {
|
|
guint mask;
|
|
|
|
/* copy relevant flags */
|
|
mask = GST_BUFFER_FLAG_PREROLL | GST_BUFFER_FLAG_IN_CAPS |
|
|
GST_BUFFER_FLAG_DELTA_UNIT | GST_BUFFER_FLAG_DISCONT |
|
|
GST_BUFFER_FLAG_GAP | GST_BUFFER_FLAG_MEDIA1 |
|
|
GST_BUFFER_FLAG_MEDIA2 | GST_BUFFER_FLAG_MEDIA3;
|
|
GST_MINI_OBJECT_FLAGS (dest) |= GST_MINI_OBJECT_FLAGS (src) & mask;
|
|
}
|
|
|
|
if (flags & GST_BUFFER_COPY_TIMESTAMPS) {
|
|
if (offset == 0) {
|
|
GST_BUFFER_TIMESTAMP (dest) = GST_BUFFER_TIMESTAMP (src);
|
|
GST_BUFFER_OFFSET (dest) = GST_BUFFER_OFFSET (src);
|
|
if (size == bufsize) {
|
|
GST_BUFFER_DURATION (dest) = GST_BUFFER_DURATION (src);
|
|
GST_BUFFER_OFFSET_END (dest) = GST_BUFFER_OFFSET_END (src);
|
|
}
|
|
} else {
|
|
GST_BUFFER_TIMESTAMP (dest) = GST_CLOCK_TIME_NONE;
|
|
GST_BUFFER_DURATION (dest) = GST_CLOCK_TIME_NONE;
|
|
GST_BUFFER_OFFSET (dest) = GST_BUFFER_OFFSET_NONE;
|
|
GST_BUFFER_OFFSET_END (dest) = GST_BUFFER_OFFSET_NONE;
|
|
}
|
|
}
|
|
|
|
if (flags & GST_BUFFER_COPY_CAPS) {
|
|
gst_caps_replace (&GST_BUFFER_CAPS (dest), GST_BUFFER_CAPS (src));
|
|
}
|
|
|
|
if (flags & GST_BUFFER_COPY_MEMORY) {
|
|
GPtrArray *sarr = GST_BUFFER_MEMORY (src);
|
|
GPtrArray *darr = GST_BUFFER_MEMORY (dest);
|
|
GstMemory *mem;
|
|
gsize left, len, i, bsize;
|
|
|
|
len = sarr->len;
|
|
left = size;
|
|
|
|
/* copy and subbuffer */
|
|
for (i = 0; i < len && left > 0; i++) {
|
|
mem = g_ptr_array_index (sarr, i);
|
|
bsize = gst_memory_get_sizes (mem, NULL);
|
|
|
|
if (bsize <= offset) {
|
|
/* don't copy buffer */
|
|
offset -= bsize;
|
|
} else {
|
|
gsize tocopy;
|
|
|
|
tocopy = MIN (bsize - offset, left);
|
|
if (tocopy < bsize) {
|
|
/* we need to clip something */
|
|
mem = gst_memory_sub (mem, offset, tocopy);
|
|
} else {
|
|
mem = gst_memory_ref (mem);
|
|
}
|
|
g_ptr_array_add (darr, mem);
|
|
left -= tocopy;
|
|
}
|
|
}
|
|
}
|
|
|
|
for (walk = GST_BUFFER_META (src); walk; walk = walk->next) {
|
|
GstMeta *meta = &walk->meta;
|
|
const GstMetaInfo *info = meta->info;
|
|
|
|
if (info->copy_func)
|
|
info->copy_func (dest, meta, src, offset, size);
|
|
}
|
|
}
|
|
|
|
static GstBuffer *
|
|
_gst_buffer_copy (GstBuffer * buffer)
|
|
{
|
|
GstBuffer *copy;
|
|
|
|
g_return_val_if_fail (buffer != NULL, NULL);
|
|
|
|
/* create a fresh new buffer */
|
|
copy = gst_buffer_new ();
|
|
|
|
/* we simply copy everything from our parent */
|
|
gst_buffer_copy_into (copy, buffer, GST_BUFFER_COPY_ALL, 0, -1);
|
|
|
|
return copy;
|
|
}
|
|
|
|
/* the default dispose function revives the buffer and returns it to the
|
|
* pool when there is a pool */
|
|
static void
|
|
_gst_buffer_dispose (GstBuffer * buffer)
|
|
{
|
|
GstBufferPool *pool;
|
|
|
|
if ((pool = buffer->pool) != NULL) {
|
|
/* keep the buffer alive */
|
|
gst_buffer_ref (buffer);
|
|
/* return the buffer to the pool */
|
|
GST_CAT_LOG (GST_CAT_BUFFER, "release %p to pool %p", buffer, pool);
|
|
gst_buffer_pool_release_buffer (pool, buffer);
|
|
}
|
|
}
|
|
|
|
static void
|
|
_gst_buffer_free (GstBuffer * buffer)
|
|
{
|
|
GstMetaItem *walk, *next;
|
|
|
|
g_return_if_fail (buffer != NULL);
|
|
|
|
GST_CAT_LOG (GST_CAT_BUFFER, "finalize %p", buffer);
|
|
|
|
gst_caps_replace (&GST_BUFFER_CAPS (buffer), NULL);
|
|
|
|
/* free metadata */
|
|
for (walk = GST_BUFFER_META (buffer); walk; walk = next) {
|
|
GstMeta *meta = &walk->meta;
|
|
const GstMetaInfo *info = meta->info;
|
|
|
|
/* call free_func if any */
|
|
if (info->free_func)
|
|
info->free_func (meta, buffer);
|
|
|
|
next = walk->next;
|
|
/* and free the slice */
|
|
g_slice_free1 (ITEM_SIZE (info), walk);
|
|
}
|
|
|
|
/* free our data, unrefs the memory too */
|
|
g_ptr_array_free (GST_BUFFER_MEMORY (buffer), TRUE);
|
|
|
|
g_slice_free1 (GST_MINI_OBJECT_SIZE (buffer), buffer);
|
|
}
|
|
|
|
static void
|
|
gst_buffer_init (GstBufferImpl * buffer, gsize size)
|
|
{
|
|
gst_mini_object_init (GST_MINI_OBJECT_CAST (buffer), _gst_buffer_type, size);
|
|
|
|
buffer->buffer.mini_object.copy =
|
|
(GstMiniObjectCopyFunction) _gst_buffer_copy;
|
|
buffer->buffer.mini_object.dispose =
|
|
(GstMiniObjectDisposeFunction) _gst_buffer_dispose;
|
|
buffer->buffer.mini_object.free =
|
|
(GstMiniObjectFreeFunction) _gst_buffer_free;
|
|
|
|
GST_BUFFER_TIMESTAMP (buffer) = GST_CLOCK_TIME_NONE;
|
|
GST_BUFFER_DURATION (buffer) = GST_CLOCK_TIME_NONE;
|
|
GST_BUFFER_OFFSET (buffer) = GST_BUFFER_OFFSET_NONE;
|
|
GST_BUFFER_OFFSET_END (buffer) = GST_BUFFER_OFFSET_NONE;
|
|
|
|
/* FIXME, do more efficient with array in the buffer memory itself */
|
|
GST_BUFFER_MEMORY (buffer) =
|
|
g_ptr_array_new_with_free_func ((GDestroyNotify) gst_memory_unref);
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_new:
|
|
*
|
|
* Creates a newly allocated buffer without any data.
|
|
*
|
|
* MT safe.
|
|
*
|
|
* Returns: (transfer full): the new #GstBuffer.
|
|
*/
|
|
GstBuffer *
|
|
gst_buffer_new (void)
|
|
{
|
|
GstBufferImpl *newbuf;
|
|
|
|
newbuf = g_slice_new0 (GstBufferImpl);
|
|
GST_CAT_LOG (GST_CAT_BUFFER, "new %p", newbuf);
|
|
|
|
gst_buffer_init (newbuf, sizeof (GstBufferImpl));
|
|
|
|
return GST_BUFFER_CAST (newbuf);
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_new_and_alloc:
|
|
* @size: the size in bytes of the new buffer's data.
|
|
*
|
|
* Tries to create a newly allocated buffer with data of the given size. If
|
|
* the requested amount of memory can't be allocated, NULL will be returned.
|
|
* The allocated buffer memory is not cleared.
|
|
*
|
|
* Note that when @size == 0, the buffer will not have memory associated with it.
|
|
*
|
|
* MT safe.
|
|
*
|
|
* Returns: (transfer full): a new #GstBuffer, or NULL if the memory couldn't
|
|
* be allocated.
|
|
*/
|
|
GstBuffer *
|
|
gst_buffer_new_and_alloc (guint size)
|
|
{
|
|
GstBuffer *newbuf;
|
|
GstMemory *mem;
|
|
|
|
if (size > 0) {
|
|
mem = gst_memory_new_alloc (size, _gst_buffer_data_alignment);
|
|
if (G_UNLIKELY (mem == NULL))
|
|
goto no_memory;
|
|
} else {
|
|
mem = NULL;
|
|
}
|
|
|
|
newbuf = gst_buffer_new ();
|
|
|
|
if (mem != NULL)
|
|
gst_buffer_take_memory (newbuf, mem);
|
|
|
|
GST_CAT_LOG (GST_CAT_BUFFER, "new %p of size %d", newbuf, size);
|
|
|
|
return newbuf;
|
|
|
|
/* ERRORS */
|
|
no_memory:
|
|
{
|
|
GST_CAT_WARNING (GST_CAT_BUFFER, "failed to allocate %d bytes", size);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_n_memory:
|
|
* @buffer: a #GstBuffer.
|
|
*
|
|
* Get the amount of memory blocks that this buffer has.
|
|
*
|
|
* Returns: (transfer full): the amount of memory block in this buffer.
|
|
*/
|
|
guint
|
|
gst_buffer_n_memory (GstBuffer * buffer)
|
|
{
|
|
g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
|
|
|
|
return GST_BUFFER_MEMORY (buffer)->len;
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_take_memory:
|
|
* @buffer: a #GstBuffer.
|
|
* @mem: a #GstMemory.
|
|
*
|
|
* Add the memory block @mem to @buffer. This function takes ownership of @mem
|
|
* and thus doesn't increase its refcount.
|
|
*/
|
|
void
|
|
gst_buffer_take_memory (GstBuffer * buffer, GstMemory * mem)
|
|
{
|
|
g_return_if_fail (GST_IS_BUFFER (buffer));
|
|
g_return_if_fail (gst_buffer_is_writable (buffer));
|
|
g_return_if_fail (mem != NULL);
|
|
|
|
g_ptr_array_add (GST_BUFFER_MEMORY (buffer), mem);
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_peek_memory:
|
|
* @buffer: a #GstBuffer.
|
|
* @idx: an index
|
|
*
|
|
* Get the memory block in @buffer at @idx. This function does not return a
|
|
* refcount to the memory block. The memory block stays valid for as long as the
|
|
* caller has a valid reference to @buffer.
|
|
*
|
|
* Returns: a #GstMemory at @idx.
|
|
*/
|
|
GstMemory *
|
|
gst_buffer_peek_memory (GstBuffer * buffer, guint idx)
|
|
{
|
|
GstMemory *mem;
|
|
GPtrArray *arr;
|
|
|
|
g_return_val_if_fail (GST_IS_BUFFER (buffer), NULL);
|
|
arr = GST_BUFFER_MEMORY (buffer);
|
|
g_return_val_if_fail (idx < arr->len, NULL);
|
|
|
|
mem = g_ptr_array_index (arr, idx);
|
|
|
|
return mem;
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_remove_memory_range:
|
|
* @buffer: a #GstBuffer.
|
|
* @idx: an index
|
|
* @length: a length
|
|
*
|
|
* Remove @len memory blocks in @buffer starting from @idx.
|
|
*
|
|
* @length can be -1, in which case all memory starting from @idx is removed.
|
|
*/
|
|
void
|
|
gst_buffer_remove_memory_range (GstBuffer * buffer, guint idx, guint length)
|
|
{
|
|
GPtrArray *arr;
|
|
|
|
g_return_if_fail (GST_IS_BUFFER (buffer));
|
|
g_return_if_fail (gst_buffer_is_writable (buffer));
|
|
arr = GST_BUFFER_MEMORY (buffer);
|
|
if (length == -1) {
|
|
g_return_if_fail (idx < arr->len);
|
|
length = arr->len - idx;
|
|
}
|
|
g_ptr_array_remove_range (arr, idx, length);
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_get_size:
|
|
* @buffer: a #GstBuffer.
|
|
*
|
|
* Get the total size of all memory blocks in @buffer.
|
|
*
|
|
* Returns: the total size of the memory in @buffer.
|
|
*/
|
|
gsize
|
|
gst_buffer_get_size (GstBuffer * buffer)
|
|
{
|
|
GPtrArray *arr;
|
|
guint i, size, len;
|
|
|
|
g_return_val_if_fail (GST_IS_BUFFER (buffer), 0);
|
|
|
|
arr = GST_BUFFER_MEMORY (buffer);
|
|
len = arr->len;
|
|
|
|
size = 0;
|
|
for (i = 0; i < len; i++) {
|
|
size += gst_memory_get_sizes (g_ptr_array_index (arr, i), NULL);
|
|
}
|
|
return size;
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_trim:
|
|
* @buffer: a #GstBuffer.
|
|
* @offset: the new offset
|
|
* @size: the new size
|
|
*
|
|
* Set the total size of the buffer
|
|
*/
|
|
void
|
|
gst_buffer_trim (GstBuffer * buffer, gsize offset, gsize size)
|
|
{
|
|
GPtrArray *arr;
|
|
guint len;
|
|
guint si, di;
|
|
gsize bsize;
|
|
GstMemory *mem;
|
|
|
|
GST_CAT_LOG (GST_CAT_BUFFER, "trim %p %" G_GSIZE_FORMAT "-%" G_GSIZE_FORMAT,
|
|
buffer, offset, size);
|
|
|
|
g_return_if_fail (gst_buffer_is_writable (buffer));
|
|
|
|
arr = GST_BUFFER_MEMORY (buffer);
|
|
len = arr->len;
|
|
|
|
/* copy and trim */
|
|
for (di = si = 0; si < len && size > 0; si++) {
|
|
mem = g_ptr_array_index (arr, si);
|
|
bsize = gst_memory_get_sizes (mem, NULL);
|
|
|
|
if (bsize <= offset) {
|
|
/* remove buffer */
|
|
gst_memory_unref (mem);
|
|
offset -= bsize;
|
|
} else {
|
|
gsize tocopy;
|
|
|
|
tocopy = MIN (bsize - offset, size);
|
|
if (tocopy < bsize) {
|
|
/* we need to clip something */
|
|
if (GST_MEMORY_IS_WRITABLE (mem)) {
|
|
gst_memory_trim (mem, offset, tocopy);
|
|
} else {
|
|
GstMemory *tmp;
|
|
tmp = gst_memory_sub (mem, offset, tocopy);
|
|
gst_memory_unref (mem);
|
|
mem = tmp;
|
|
}
|
|
}
|
|
g_ptr_array_index (arr, di++) = mem;
|
|
size -= tocopy;
|
|
}
|
|
}
|
|
g_ptr_array_set_size (arr, di);
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_map:
|
|
* @buffer: a #GstBuffer.
|
|
* @size: a location for the size
|
|
* @maxsize: a location for the max size
|
|
* @flags: flags for the mapping
|
|
*
|
|
* This function return a pointer to the memory in @buffer. @flags describe the
|
|
* desired access of the memory. When @flags is #GST_MAP_WRITE, @buffer should
|
|
* be writable (as returned from gst_buffer_is_writable()).
|
|
*
|
|
* @size and @maxsize will contain the current valid number of bytes in the
|
|
* returned memory area and the total maximum mount of bytes available in the
|
|
* returned memory area respectively.
|
|
*
|
|
* When @buffer is writable but the memory isn't, a writable copy will
|
|
* automatically be created and returned. The readonly copy of the buffer memory
|
|
* will then also be replaced with this writable copy.
|
|
*
|
|
* When the buffer contains multiple memory blocks, the returned pointer will be
|
|
* a concatenation of the memory blocks.
|
|
*
|
|
* Returns: a pointer to the memory for the buffer.
|
|
*/
|
|
gpointer
|
|
gst_buffer_map (GstBuffer * buffer, gsize * size, gsize * maxsize,
|
|
GstMapFlags flags)
|
|
{
|
|
GPtrArray *arr;
|
|
guint len;
|
|
gpointer data;
|
|
|
|
g_return_val_if_fail (GST_IS_BUFFER (buffer), NULL);
|
|
|
|
arr = GST_BUFFER_MEMORY (buffer);
|
|
len = arr->len;
|
|
|
|
if (G_UNLIKELY ((flags & GST_MAP_WRITE) && !gst_buffer_is_writable (buffer)))
|
|
goto not_writable;
|
|
|
|
if (G_LIKELY (len == 1)) {
|
|
GstMemory *mem;
|
|
|
|
mem = g_ptr_array_index (arr, 0);
|
|
|
|
if (flags & GST_MAP_WRITE) {
|
|
if (G_UNLIKELY (!GST_MEMORY_IS_WRITABLE (mem))) {
|
|
GstMemory *copy;
|
|
|
|
/* replace with a writable copy */
|
|
copy = gst_memory_copy (mem, 0, gst_memory_get_sizes (mem, NULL));
|
|
g_ptr_array_index (arr, 0) = copy;
|
|
gst_memory_unref (mem);
|
|
mem = copy;
|
|
}
|
|
}
|
|
|
|
data = gst_memory_map (mem, size, maxsize, flags);
|
|
} else {
|
|
/* FIXME, implement me */
|
|
data = NULL;
|
|
if (size)
|
|
*size = 0;
|
|
}
|
|
return data;
|
|
|
|
/* ERROR */
|
|
not_writable:
|
|
{
|
|
g_return_val_if_fail (gst_buffer_is_writable (buffer), NULL);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_unmap:
|
|
* @buffer: a #GstBuffer.
|
|
* @data: the previously mapped data
|
|
* @size: the size of @data
|
|
*
|
|
* Release the memory previously mapped with gst_buffer_map().
|
|
*
|
|
* Returns: #TRUE on success. #FALSE can be returned when the new size is larger
|
|
* than the maxsize of the memory.
|
|
*/
|
|
gboolean
|
|
gst_buffer_unmap (GstBuffer * buffer, gpointer data, gsize size)
|
|
{
|
|
GPtrArray *arr;
|
|
gboolean result;
|
|
guint len;
|
|
|
|
g_return_val_if_fail (GST_IS_BUFFER (buffer), FALSE);
|
|
|
|
arr = GST_BUFFER_MEMORY (buffer);
|
|
len = arr->len;
|
|
|
|
if (G_LIKELY (len == 1)) {
|
|
GstMemory *mem = g_ptr_array_index (arr, 0);
|
|
|
|
result = gst_memory_unmap (mem, data, size);
|
|
} else {
|
|
/* FIXME, implement me */
|
|
result = FALSE;
|
|
}
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_fill:
|
|
* @buffer: a #GstBuffer.
|
|
* @offset: the offset to fill
|
|
* @src: the source address
|
|
* @size: the size to fill
|
|
*
|
|
* Copy @size bytes fro @src to @buffer at @offset.
|
|
*/
|
|
void
|
|
gst_buffer_fill (GstBuffer * buffer, gsize offset, gconstpointer src,
|
|
gsize size)
|
|
{
|
|
GPtrArray *arr;
|
|
gsize i, len;
|
|
const guint8 *ptr = src;
|
|
|
|
g_return_if_fail (GST_IS_BUFFER (buffer));
|
|
g_return_if_fail (gst_buffer_is_writable (buffer));
|
|
g_return_if_fail (src != NULL);
|
|
|
|
arr = GST_BUFFER_MEMORY (buffer);
|
|
len = arr->len;
|
|
|
|
for (i = 0; i < len && size > 0; i++) {
|
|
guint8 *data;
|
|
gsize ssize, tocopy;
|
|
GstMemory *mem;
|
|
|
|
mem = g_ptr_array_index (arr, i);
|
|
|
|
data = gst_memory_map (mem, &ssize, NULL, GST_MAP_WRITE);
|
|
if (ssize > offset) {
|
|
/* we have enough */
|
|
tocopy = MIN (ssize - offset, size);
|
|
memcpy (data + offset, ptr, tocopy);
|
|
size -= tocopy;
|
|
ptr += tocopy;
|
|
offset = 0;
|
|
} else {
|
|
/* offset past buffer, skip */
|
|
offset -= ssize;
|
|
}
|
|
gst_memory_unmap (mem, data, ssize);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_extract:
|
|
* @buffer: a #GstBuffer.
|
|
* @offset: the offset to extract
|
|
* @dest: the destination address
|
|
* @size: the size to extract
|
|
*
|
|
* Copy @size bytes starting from @offset in @buffer to @dest.
|
|
*/
|
|
void
|
|
gst_buffer_extract (GstBuffer * buffer, gsize offset, gpointer dest, gsize size)
|
|
{
|
|
GPtrArray *arr;
|
|
gsize i, len;
|
|
guint8 *ptr = dest;
|
|
|
|
g_return_if_fail (GST_IS_BUFFER (buffer));
|
|
g_return_if_fail (dest != NULL);
|
|
|
|
arr = GST_BUFFER_MEMORY (buffer);
|
|
len = arr->len;
|
|
|
|
for (i = 0; i < len && size > 0; i++) {
|
|
guint8 *data;
|
|
gsize ssize, tocopy;
|
|
GstMemory *mem;
|
|
|
|
mem = g_ptr_array_index (arr, i);
|
|
|
|
data = gst_memory_map (mem, &ssize, NULL, GST_MAP_READ);
|
|
if (ssize > offset) {
|
|
/* we have enough */
|
|
tocopy = MIN (ssize - offset, size);
|
|
memcpy (ptr, data + offset, tocopy);
|
|
size -= tocopy;
|
|
ptr += tocopy;
|
|
offset = 0;
|
|
} else {
|
|
/* offset past buffer, skip */
|
|
offset -= ssize;
|
|
}
|
|
gst_memory_unmap (mem, data, ssize);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_get_caps:
|
|
* @buffer: a #GstBuffer.
|
|
*
|
|
* Gets the media type of the buffer. This can be NULL if there
|
|
* is no media type attached to this buffer.
|
|
*
|
|
* Returns: (transfer full): a reference to the #GstCaps. unref after usage.
|
|
* Returns NULL if there were no caps on this buffer.
|
|
*/
|
|
/* this is not made atomic because if the buffer were reffed from multiple
|
|
* threads, it would have a refcount > 2 and thus be immutable.
|
|
*/
|
|
GstCaps *
|
|
gst_buffer_get_caps (GstBuffer * buffer)
|
|
{
|
|
GstCaps *ret;
|
|
|
|
g_return_val_if_fail (buffer != NULL, NULL);
|
|
|
|
ret = GST_BUFFER_CAPS (buffer);
|
|
|
|
if (ret)
|
|
gst_caps_ref (ret);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_set_caps:
|
|
* @buffer: a #GstBuffer.
|
|
* @caps: (transfer none): a #GstCaps.
|
|
*
|
|
* Sets the media type on the buffer. The refcount of the caps will
|
|
* be increased and any previous caps on the buffer will be
|
|
* unreffed.
|
|
*/
|
|
/* this is not made atomic because if the buffer were reffed from multiple
|
|
* threads, it would have a refcount > 2 and thus be immutable.
|
|
*/
|
|
void
|
|
gst_buffer_set_caps (GstBuffer * buffer, GstCaps * caps)
|
|
{
|
|
g_return_if_fail (buffer != NULL);
|
|
g_return_if_fail (caps == NULL || GST_CAPS_IS_SIMPLE (caps));
|
|
|
|
#if GST_VERSION_NANO == 1
|
|
/* we enable this extra debugging in git versions only for now */
|
|
g_warn_if_fail (gst_buffer_is_writable (buffer));
|
|
/* FIXME: would be nice to also check if caps are fixed here, but expensive */
|
|
#endif
|
|
|
|
gst_caps_replace (&GST_BUFFER_CAPS (buffer), caps);
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_create_sub:
|
|
* @parent: a #GstBuffer.
|
|
* @offset: the offset into parent #GstBuffer at which the new sub-buffer
|
|
* begins.
|
|
* @size: the size of the new #GstBuffer sub-buffer, in bytes.
|
|
*
|
|
* Creates a sub-buffer from @parent at @offset and @size.
|
|
* This sub-buffer uses the actual memory space of the parent buffer.
|
|
* This function will copy the offset and timestamp fields when the
|
|
* offset is 0. If not, they will be set to #GST_CLOCK_TIME_NONE and
|
|
* #GST_BUFFER_OFFSET_NONE.
|
|
* If @offset equals 0 and @size equals the total size of @buffer, the
|
|
* duration and offset end fields are also copied. If not they will be set
|
|
* to #GST_CLOCK_TIME_NONE and #GST_BUFFER_OFFSET_NONE.
|
|
*
|
|
* MT safe.
|
|
*
|
|
* Returns: (transfer full): the new #GstBuffer or NULL if the arguments were
|
|
* invalid.
|
|
*/
|
|
GstBuffer *
|
|
gst_buffer_create_sub (GstBuffer * buffer, gsize offset, gsize size)
|
|
{
|
|
GstBuffer *subbuffer;
|
|
gsize bufsize;
|
|
|
|
g_return_val_if_fail (buffer != NULL, NULL);
|
|
g_return_val_if_fail (buffer->mini_object.refcount > 0, NULL);
|
|
|
|
bufsize = gst_buffer_get_size (buffer);
|
|
g_return_val_if_fail (bufsize >= offset + size, NULL);
|
|
|
|
/* create the new buffer */
|
|
subbuffer = gst_buffer_new ();
|
|
|
|
GST_CAT_LOG (GST_CAT_BUFFER, "new subbuffer %p of %p %" G_GSIZE_FORMAT
|
|
"-%" G_GSIZE_FORMAT, subbuffer, buffer, offset, size);
|
|
|
|
gst_buffer_copy_into (subbuffer, buffer, GST_BUFFER_COPY_ALL, offset, size);
|
|
|
|
return subbuffer;
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_is_span_fast:
|
|
* @buf1: the first #GstBuffer.
|
|
* @buf2: the second #GstBuffer.
|
|
*
|
|
* Determines whether a gst_buffer_span() can be done without copying
|
|
* the contents, that is, whether the data areas are contiguous sub-buffers of
|
|
* the same buffer.
|
|
*
|
|
* MT safe.
|
|
* Returns: TRUE if the buffers are contiguous,
|
|
* FALSE if a copy would be required.
|
|
*/
|
|
gboolean
|
|
gst_buffer_is_span_fast (GstBuffer * buf1, GstBuffer * buf2)
|
|
{
|
|
GPtrArray *arr1, *arr2;
|
|
|
|
g_return_val_if_fail (GST_IS_BUFFER (buf1), FALSE);
|
|
g_return_val_if_fail (GST_IS_BUFFER (buf2), FALSE);
|
|
g_return_val_if_fail (buf1->mini_object.refcount > 0, FALSE);
|
|
g_return_val_if_fail (buf2->mini_object.refcount > 0, FALSE);
|
|
|
|
arr1 = GST_BUFFER_MEMORY (buf1);
|
|
arr2 = GST_BUFFER_MEMORY (buf2);
|
|
|
|
return gst_memory_is_span ((GstMemory **) arr1->pdata, arr1->len,
|
|
(GstMemory **) arr2->pdata, arr2->len, NULL, NULL);
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_span:
|
|
* @buf1: the first source #GstBuffer to merge.
|
|
* @offset: the offset in the first buffer from where the new
|
|
* buffer should start.
|
|
* @buf2: the second source #GstBuffer to merge.
|
|
* @len: the total length of the new buffer.
|
|
*
|
|
* Creates a new buffer that consists of part of buf1 and buf2.
|
|
* Logically, buf1 and buf2 are concatenated into a single larger
|
|
* buffer, and a new buffer is created at the given offset inside
|
|
* this space, with a given length.
|
|
*
|
|
* If the two source buffers are children of the same larger buffer,
|
|
* and are contiguous, the new buffer will be a child of the shared
|
|
* parent, and thus no copying is necessary. you can use
|
|
* gst_buffer_is_span_fast() to determine if a memcpy will be needed.
|
|
*
|
|
* MT safe.
|
|
*
|
|
* Returns: (transfer full): the new #GstBuffer that spans the two source
|
|
* buffers, or NULL if the arguments are invalid.
|
|
*/
|
|
GstBuffer *
|
|
gst_buffer_span (GstBuffer * buf1, gsize offset, GstBuffer * buf2, gsize len)
|
|
{
|
|
GstBuffer *newbuf;
|
|
GPtrArray *arr1, *arr2;
|
|
GstMemory *mem;
|
|
|
|
g_return_val_if_fail (GST_IS_BUFFER (buf1), NULL);
|
|
g_return_val_if_fail (GST_IS_BUFFER (buf2), NULL);
|
|
g_return_val_if_fail (buf1->mini_object.refcount > 0, NULL);
|
|
g_return_val_if_fail (buf2->mini_object.refcount > 0, NULL);
|
|
g_return_val_if_fail (len > 0, NULL);
|
|
g_return_val_if_fail (len <= gst_buffer_get_size (buf1) +
|
|
gst_buffer_get_size (buf2) - offset, NULL);
|
|
|
|
newbuf = gst_buffer_new ();
|
|
|
|
arr1 = GST_BUFFER_MEMORY (buf1);
|
|
arr2 = GST_BUFFER_MEMORY (buf2);
|
|
|
|
mem = gst_memory_span ((GstMemory **) arr1->pdata, arr1->len, offset,
|
|
(GstMemory **) arr2->pdata, arr2->len, len);
|
|
gst_buffer_take_memory (newbuf, mem);
|
|
|
|
#if 0
|
|
/* if the offset is 0, the new buffer has the same timestamp as buf1 */
|
|
if (offset == 0) {
|
|
GST_BUFFER_OFFSET (newbuf) = GST_BUFFER_OFFSET (buf1);
|
|
GST_BUFFER_TIMESTAMP (newbuf) = GST_BUFFER_TIMESTAMP (buf1);
|
|
|
|
/* if we completely merged the two buffers (appended), we can
|
|
* calculate the duration too. Also make sure we's not messing with
|
|
* invalid DURATIONS */
|
|
if (buf1->size + buf2->size == len) {
|
|
if (GST_BUFFER_DURATION_IS_VALID (buf1) &&
|
|
GST_BUFFER_DURATION_IS_VALID (buf2)) {
|
|
/* add duration */
|
|
GST_BUFFER_DURATION (newbuf) = GST_BUFFER_DURATION (buf1) +
|
|
GST_BUFFER_DURATION (buf2);
|
|
}
|
|
if (GST_BUFFER_OFFSET_END_IS_VALID (buf2)) {
|
|
/* add offset_end */
|
|
GST_BUFFER_OFFSET_END (newbuf) = GST_BUFFER_OFFSET_END (buf2);
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
|
|
return newbuf;
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_get_meta:
|
|
* @buffer: a #GstBuffer
|
|
* @info: a #GstMetaInfo
|
|
*
|
|
* Get the metadata for the api in @info on buffer. When there is no such
|
|
* metadata, NULL is returned.
|
|
*
|
|
* Note that the result metadata might not be of the implementation @info.
|
|
*
|
|
* Returns: the metadata for the api in @info on @buffer.
|
|
*/
|
|
GstMeta *
|
|
gst_buffer_get_meta (GstBuffer * buffer, const GstMetaInfo * info)
|
|
{
|
|
GstMetaItem *item;
|
|
GstMeta *result = NULL;
|
|
|
|
g_return_val_if_fail (buffer != NULL, NULL);
|
|
g_return_val_if_fail (info != NULL, NULL);
|
|
|
|
/* find GstMeta of the requested API */
|
|
for (item = GST_BUFFER_META (buffer); item; item = item->next) {
|
|
GstMeta *meta = &item->meta;
|
|
if (meta->info->api == info->api) {
|
|
result = meta;
|
|
break;
|
|
}
|
|
}
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_add_meta:
|
|
* @buffer: a #GstBuffer
|
|
* @info: a #GstMetaInfo
|
|
* @params: params for @info
|
|
*
|
|
* Add metadata for @info to @buffer using the parameters in @params.
|
|
*
|
|
* Returns: the metadata for the api in @info on @buffer.
|
|
*/
|
|
GstMeta *
|
|
gst_buffer_add_meta (GstBuffer * buffer, const GstMetaInfo * info,
|
|
gpointer params)
|
|
{
|
|
GstMetaItem *item;
|
|
GstMeta *result = NULL;
|
|
gsize size;
|
|
|
|
g_return_val_if_fail (buffer != NULL, NULL);
|
|
g_return_val_if_fail (info != NULL, NULL);
|
|
|
|
/* create a new slice */
|
|
GST_CAT_DEBUG (GST_CAT_BUFFER, "alloc metadata of size %" G_GSIZE_FORMAT,
|
|
info->size);
|
|
|
|
size = ITEM_SIZE (info);
|
|
item = g_slice_alloc (size);
|
|
result = &item->meta;
|
|
result->info = info;
|
|
|
|
/* call the init_func when needed */
|
|
if (info->init_func)
|
|
if (!info->init_func (result, params, buffer))
|
|
goto init_failed;
|
|
|
|
/* and add to the list of metadata */
|
|
item->next = GST_BUFFER_META (buffer);
|
|
GST_BUFFER_META (buffer) = item;
|
|
|
|
return result;
|
|
|
|
init_failed:
|
|
{
|
|
g_slice_free1 (size, item);
|
|
return NULL;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_remove_meta:
|
|
* @buffer: a #GstBuffer
|
|
* @info: a #GstMetaInfo
|
|
*
|
|
* Remove the metadata for @info on @buffer.
|
|
*
|
|
* Returns: %TRUE if the metadata existed and was removed, %FALSE if no such
|
|
* metadata was on @buffer.
|
|
*/
|
|
gboolean
|
|
gst_buffer_remove_meta (GstBuffer * buffer, GstMeta * meta)
|
|
{
|
|
GstMetaItem *walk, *prev;
|
|
|
|
g_return_val_if_fail (buffer != NULL, FALSE);
|
|
g_return_val_if_fail (meta != NULL, FALSE);
|
|
|
|
/* find the metadata and delete */
|
|
prev = GST_BUFFER_META (buffer);
|
|
for (walk = prev; walk; walk = walk->next) {
|
|
GstMeta *m = &walk->meta;
|
|
if (m == meta) {
|
|
const GstMetaInfo *info = meta->info;
|
|
|
|
/* remove from list */
|
|
if (GST_BUFFER_META (buffer) == walk)
|
|
GST_BUFFER_META (buffer) = walk->next;
|
|
else
|
|
prev->next = walk->next;
|
|
/* call free_func if any */
|
|
if (info->free_func)
|
|
info->free_func (m, buffer);
|
|
|
|
/* and free the slice */
|
|
g_slice_free1 (ITEM_SIZE (info), walk);
|
|
break;
|
|
}
|
|
prev = walk;
|
|
}
|
|
return walk != NULL;
|
|
}
|
|
|
|
/**
|
|
* gst_buffer_iterate_meta:
|
|
* @buffer: a #GstBuffer
|
|
* @state: an opaque state pointer
|
|
*
|
|
* Retrieve the next #GstMeta after @current. If @state points
|
|
* to %NULL, the first metadata is returned.
|
|
*
|
|
* @state will be updated with an opage state pointer
|
|
*
|
|
* Returns: The next #GstMeta or %NULL when there are no more items.
|
|
*/
|
|
GstMeta *
|
|
gst_buffer_iterate_meta (GstBuffer * buffer, gpointer * state)
|
|
{
|
|
GstMetaItem **meta;
|
|
|
|
g_return_val_if_fail (buffer != NULL, NULL);
|
|
g_return_val_if_fail (state != NULL, NULL);
|
|
|
|
meta = (GstMetaItem **) state;
|
|
if (*meta == NULL)
|
|
/* state NULL, move to first item */
|
|
*meta = GST_BUFFER_META (buffer);
|
|
else
|
|
/* state !NULL, move to next item in list */
|
|
*meta = (*meta)->next;
|
|
|
|
if (*meta)
|
|
return &(*meta)->meta;
|
|
else
|
|
return NULL;
|
|
}
|