GstBufferList

typedef struct _GstBufferList GstBufferList;

Opaque list of grouped buffers.

GstBufferListIterator

typedef struct _GstBufferListIterator GstBufferListIterator;

Opaque iterator for a GstBufferList.

GstBufferListDoFunction ()

GstBuffer*          (*GstBufferListDoFunction)          (GstBuffer *buffer,
                                                         gpointer user_data);

A function for accessing the last buffer returned by gst_buffer_list_iterator_next(). The function can leave buffer in the list, replace buffer in the list or remove buffer from the list, depending on the return value. If the function returns NULL, buffer will be removed from the list, otherwise buffer will be replaced with the returned buffer.

The last buffer returned by gst_buffer_list_iterator_next() will be replaced with the buffer returned from the function. The function takes ownership of buffer and if a different value than buffer is returned, buffer must be unreffed. If NULL is returned, the buffer will be removed from the list. The list must be writable.

gst_buffer_list_new ()

GstBufferList*      gst_buffer_list_new                 (void);

Creates a new, empty GstBufferList. The caller is responsible for unreffing the returned GstBufferList.

gst_buffer_list_ref ()

GstBufferList*      gst_buffer_list_ref                 (GstBufferList *list);

Increases the refcount of the given buffer list by one.

Note that the refcount affects the writeability of list and its data, see gst_buffer_list_make_writable(). It is important to note that keeping additional references to GstBufferList instances can potentially increase the number of memcpy operations in a pipeline.

gst_buffer_list_unref ()

void                gst_buffer_list_unref               (GstBufferList *list);

Decreases the refcount of the buffer list. If the refcount reaches 0, the buffer list will be freed.

gst_buffer_list_copy ()

GstBufferList*      gst_buffer_list_copy                (const GstBufferList *list);

Create a shallow copy of the given buffer list. This will make a newly allocated copy of the source list with copies of buffer pointers. The refcount of buffers pointed to will be increased by one.

gst_buffer_list_is_writable()

#define gst_buffer_list_is_writable(list) gst_mini_object_is_writable (GST_MINI_OBJECT_CAST (list))

Tests if you can safely add buffers and groups into a buffer list.

gst_buffer_list_make_writable()

#define gst_buffer_list_make_writable(list) GST_BUFFER_LIST_CAST (gst_mini_object_make_writable (GST_MINI_OBJECT_CAST (list)))

Makes a writable buffer list from the given buffer list. If the source buffer list is already writable, this will simply return the same buffer list. A copy will otherwise be made using gst_buffer_list_copy().

gst_buffer_list_n_groups ()

guint               gst_buffer_list_n_groups            (GstBufferList *list);

Returns the number of groups in list.

enum GstBufferListItem

typedef enum {
  GST_BUFFER_LIST_CONTINUE,
  GST_BUFFER_LIST_SKIP_GROUP,
  GST_BUFFER_LIST_END
} GstBufferListItem;

The result of the GstBufferListFunc.

GstBufferListFunc ()

GstBufferListItem   (*GstBufferListFunc)                (GstBuffer **buffer,
                                                         guint group,
                                                         guint idx,
                                                         gpointer user_data);

A function that will be called from gst_buffer_list_foreach(). The buffer field will point to a the reference of the buffer at idx in group.

When this function returns GST_BUFFER_LIST_CONTINUE, the next buffer will be returned. When GST_BUFFER_LIST_SKIP_GROUP is returned, all remaining buffers in the current group will be skipped and the first buffer of the next group is returned (if any). When GST_BUFFER_LIST_END is returned, gst_buffer_list_foreach() will return.

When buffer is set to NULL, the item will be removed from the bufferlist. When buffer has been made writable, the new buffer reference can be assigned to buffer. This function is responsible for unreffing the old buffer when removing or modifying.

gst_buffer_list_foreach ()

void                gst_buffer_list_foreach             (GstBufferList *list,
                                                         GstBufferListFunc func,
                                                         gpointer user_data);

Call func with data for each buffer in list.

func can modify the passed buffer pointer or its contents. The return value of func define if this function returns or if the remaining buffers in a group should be skipped.

gst_buffer_list_get ()

GstBuffer*          gst_buffer_list_get                 (GstBufferList *list,
                                                         guint group,
                                                         guint idx);

Get the buffer at idx in group.

Note that this function is not efficient for iterating over the entire list. Use an iterator or gst_buffer_list_foreach() instead.

gst_buffer_list_iterate ()

GstBufferListIterator* gst_buffer_list_iterate          (GstBufferList *list);

Iterate the buffers in list. The owner of the iterator must also be the owner of a reference to list while the returned iterator is in use.

gst_buffer_list_iterator_free ()

void                gst_buffer_list_iterator_free       (GstBufferListIterator *it);

Free the iterator.

gst_buffer_list_iterator_n_buffers ()

guint               gst_buffer_list_iterator_n_buffers  (const GstBufferListIterator *it);

Returns the number of buffers left to iterate in the current group. I.e. the number of calls that can be made to gst_buffer_list_iterator_next() before it returns NULL.

This function will not move the implicit cursor or in any other way affect the state of the iterator it.

gst_buffer_list_iterator_add ()

void                gst_buffer_list_iterator_add        (GstBufferListIterator *it,
                                                         GstBuffer *buffer);

Inserts buffer into the GstBufferList iterated with it. The buffer is inserted into the current group, immediately before the buffer that would be returned by gst_buffer_list_iterator_next(). The buffer is inserted before the implicit cursor, a subsequent call to gst_buffer_list_iterator_next() will return the buffer after the inserted buffer, if any.

This function takes ownership of buffer.

gst_buffer_list_iterator_add_group ()

void                gst_buffer_list_iterator_add_group  (GstBufferListIterator *it);

Inserts a new, empty group into the GstBufferList iterated with it. The group is inserted immediately before the group that would be returned by gst_buffer_list_iterator_next_group(). A subsequent call to gst_buffer_list_iterator_next_group() will advance the iterator to the group after the inserted group, if any.

gst_buffer_list_iterator_next ()

GstBuffer*          gst_buffer_list_iterator_next       (GstBufferListIterator *it);

Returns the next buffer in the list iterated with it. If the iterator is at the end of a group, NULL will be returned. This function may be called repeatedly to iterate through the current group.

The caller will not get a new ref to the returned GstBuffer and must not unref it.

gst_buffer_list_iterator_next_group ()

gboolean            gst_buffer_list_iterator_next_group (GstBufferListIterator *it);

Advance the iterator it to the first buffer in the next group. If the iterator is at the last group, FALSE will be returned. This function may be called repeatedly to iterate through the groups in a buffer list.

gst_buffer_list_iterator_remove ()

void                gst_buffer_list_iterator_remove     (GstBufferListIterator *it);

Removes the last buffer returned by gst_buffer_list_iterator_next() from the GstBufferList iterated with it. gst_buffer_list_iterator_next() must have been called on it before this function is called. This function can only be called once per call to gst_buffer_list_iterator_next().

The removed buffer is unreffed.

gst_buffer_list_iterator_steal ()

GstBuffer*          gst_buffer_list_iterator_steal      (GstBufferListIterator *it);

Returns the last buffer returned by gst_buffer_list_iterator_next() without modifying the refcount of the buffer.

gst_buffer_list_iterator_take ()

void                gst_buffer_list_iterator_take       (GstBufferListIterator *it,
                                                         GstBuffer *buffer);

Replaces the last buffer returned by gst_buffer_list_iterator_next() with buffer in the GstBufferList iterated with it and takes ownership of buffer. gst_buffer_list_iterator_next() must have been called on it before this function is called. gst_buffer_list_iterator_remove() must not have been called since the last call to gst_buffer_list_iterator_next().

This function unrefs the replaced buffer if it has not been stolen with gst_buffer_list_iterator_steal() and takes ownership of buffer (i.e. the refcount of buffer is not increased).

gst_buffer_list_iterator_do ()

GstBuffer*          gst_buffer_list_iterator_do         (GstBufferListIterator *it,
                                                         GstBufferListDoFunction do_func,
                                                         gpointer user_data);

Calls the given function for the last buffer returned by gst_buffer_list_iterator_next(). gst_buffer_list_iterator_next() must have been called on it before this function is called. gst_buffer_list_iterator_remove() and gst_buffer_list_iterator_steal() must not have been called since the last call to gst_buffer_list_iterator_next().

See GstBufferListDoFunction for more details.

gst_buffer_list_iterator_merge_group ()

GstBuffer*          gst_buffer_list_iterator_merge_group
                                                        (const GstBufferListIterator *it);

Merge a buffer list group into a normal GstBuffer by copying its metadata and memcpying its data into consecutive memory. All buffers in the current group after the implicit cursor will be merged into one new buffer. The metadata of the new buffer will be a copy of the metadata of the buffer that would be returned by gst_buffer_list_iterator_next(). If there is no buffer in the current group after the implicit cursor, NULL will be returned.

This function will not move the implicit cursor or in any other way affect the state of the iterator it or the list.