GST_BUFFER_POOL_IS_FLUSHING()

#define GST_BUFFER_POOL_IS_FLUSHING(pool)  (g_atomic_int_get (&pool->flushing))

Check if the bufferpool is flushing. Subclasses might want to check the state of the pool in the acquire function.

gst_buffer_pool_new ()

GstBufferPool *
gst_buffer_pool_new (void);

Creates a new GstBufferPool instance.

gst_buffer_pool_config_get_params ()

gboolean
gst_buffer_pool_config_get_params (GstStructure *config,
                                   GstCaps **caps,
                                   guint *size,
                                   guint *min_buffers,
                                   guint *max_buffers);

Get the configuration values from config .

gst_buffer_pool_config_set_params ()

void
gst_buffer_pool_config_set_params (GstStructure *config,
                                   GstCaps *caps,
                                   guint size,
                                   guint min_buffers,
                                   guint max_buffers);

Configure config with the given parameters.

gst_buffer_pool_config_validate_params ()

gboolean
gst_buffer_pool_config_validate_params
                               (GstStructure *config,
                                GstCaps *caps,
                                guint size,
                                guint min_buffers,
                                guint max_buffers);

Validate that changes made to config are still valid in the context of the expected parameters. This function is a helper that can be used to validate changes made by a pool to a config when gst_buffer_pool_set_config() returns FALSE. This expects that caps haven't changed and that min_buffers aren't lower then what we initially expected. This does not check if options or allocator parameters are still valid, won't check if size have changed, since changing the size is valid to adapt padding.

Since: 1.4

gst_buffer_pool_config_get_allocator ()

gboolean
gst_buffer_pool_config_get_allocator (GstStructure *config,
                                      GstAllocator **allocator,
                                      GstAllocationParams *params);

Get the allocator and params from config .

gst_buffer_pool_config_set_allocator ()

void
gst_buffer_pool_config_set_allocator (GstStructure *config,
                                      GstAllocator *allocator,
                                      const GstAllocationParams *params);

Set the allocator and params on config .

One of allocator and params can be NULL, but not both. When allocator is NULL, the default allocator of the pool will use the values in param to perform its allocation. When param is NULL, the pool will use the provided allocator with its default GstAllocationParams.

A call to gst_buffer_pool_set_config() can update the allocator and params with the values that it is able to do. Some pools are, for example, not able to operate with different allocators or cannot allocate with the values specified in params . Use gst_buffer_pool_get_config() to get the currently used values.

gst_buffer_pool_config_n_options ()

guint
gst_buffer_pool_config_n_options (GstStructure *config);

Retrieve the number of values currently stored in the options array of the config structure.

gst_buffer_pool_config_add_option ()

void
gst_buffer_pool_config_add_option (GstStructure *config,
                                   const gchar *option);

Enabled the option in config . This will instruct the bufferpool to enable the specified option on the buffers that it allocates.

The supported options by pool can be retrieved with gst_buffer_pool_get_options().

gst_buffer_pool_config_get_option ()

const gchar *
gst_buffer_pool_config_get_option (GstStructure *config,
                                   guint index);

Parse an available config and get the option at index of the options API array.

gst_buffer_pool_config_has_option ()

gboolean
gst_buffer_pool_config_has_option (GstStructure *config,
                                   const gchar *option);

Check if config contains option .

gst_buffer_pool_get_options ()

const gchar **
gst_buffer_pool_get_options (GstBufferPool *pool);

Get a NULL terminated array of string with supported bufferpool options for pool . An option would typically be enabled with gst_buffer_pool_config_add_option().

gst_buffer_pool_has_option ()

gboolean
gst_buffer_pool_has_option (GstBufferPool *pool,
                            const gchar *option);

Check if the bufferpool supports option .

gst_buffer_pool_get_config ()

GstStructure *
gst_buffer_pool_get_config (GstBufferPool *pool);

Get a copy of the current configuration of the pool. This configuration can either be modified and used for the gst_buffer_pool_set_config() call or it must be freed after usage.

gst_buffer_pool_set_config ()

gboolean
gst_buffer_pool_set_config (GstBufferPool *pool,
                            GstStructure *config);

Set the configuration of the pool. If the pool is already configured, and the configuration haven't change, this function will return TRUE. If the pool is active, this method will return FALSE and active configuration will remain. Buffers allocated form this pool must be returned or else this function will do nothing and return FALSE.

config is a GstStructure that contains the configuration parameters for the pool. A default and mandatory set of parameters can be configured with gst_buffer_pool_config_set_params(), gst_buffer_pool_config_set_allocator() and gst_buffer_pool_config_add_option().

If the parameters in config can not be set exactly, this function returns FALSE and will try to update as much state as possible. The new state can then be retrieved and refined with gst_buffer_pool_get_config().

This function takes ownership of config .

gst_buffer_pool_set_active ()

gboolean
gst_buffer_pool_set_active (GstBufferPool *pool,
                            gboolean active);

Control the active state of pool . When the pool is inactive, new calls to gst_buffer_pool_acquire_buffer() will return with GST_FLOW_FLUSHING.

Activating the bufferpool will preallocate all resources in the pool based on the configuration of the pool.

Deactivating will free the resources again when there are no outstanding buffers. When there are outstanding buffers, they will be freed as soon as they are all returned to the pool.

gst_buffer_pool_is_active ()

gboolean
gst_buffer_pool_is_active (GstBufferPool *pool);

Check if pool is active. A pool can be activated with the gst_buffer_pool_set_active() call.

gst_buffer_pool_set_flushing ()

void
gst_buffer_pool_set_flushing (GstBufferPool *pool,
                              gboolean flushing);

Enable or disable the flushing state of a pool without freeing or allocating buffers.

Since: 1.4

gst_buffer_pool_acquire_buffer ()

GstFlowReturn
gst_buffer_pool_acquire_buffer (GstBufferPool *pool,
                                GstBuffer **buffer,
                                GstBufferPoolAcquireParams *params);

Acquire a buffer from pool . buffer should point to a memory location that can hold a pointer to the new buffer.

params can be NULL or contain optional parameters to influence the allocation.

gst_buffer_pool_release_buffer ()

void
gst_buffer_pool_release_buffer (GstBufferPool *pool,
                                GstBuffer *buffer);

Release buffer to pool . buffer should have previously been allocated from pool with gst_buffer_pool_acquire_buffer().

This function is usually called automatically when the last ref on buffer disappears.

GstBufferPool

typedef struct _GstBufferPool GstBufferPool;

The structure of a GstBufferPool. Use the associated macros to access the public variables.

struct GstBufferPoolClass

struct GstBufferPoolClass {
  GstObjectClass    object_class;

  const gchar ** (*get_options)    (GstBufferPool *pool);
  gboolean       (*set_config)     (GstBufferPool *pool, GstStructure *config);

  gboolean       (*start)          (GstBufferPool *pool);
  gboolean       (*stop)           (GstBufferPool *pool);

  GstFlowReturn  (*acquire_buffer) (GstBufferPool *pool, GstBuffer **buffer,
                                    GstBufferPoolAcquireParams *params);
  GstFlowReturn  (*alloc_buffer)   (GstBufferPool *pool, GstBuffer **buffer,
                                    GstBufferPoolAcquireParams *params);
  void           (*reset_buffer)   (GstBufferPool *pool, GstBuffer *buffer);
  void           (*release_buffer) (GstBufferPool *pool, GstBuffer *buffer);
  void           (*free_buffer)    (GstBufferPool *pool, GstBuffer *buffer);
  void           (*flush_start)    (GstBufferPool *pool);
  void           (*flush_stop)     (GstBufferPool *pool);
};

The GstBufferPool class.

enum GstBufferPoolAcquireFlags

Additional flags to control the allocation of a buffer

struct GstBufferPoolAcquireParams

struct GstBufferPoolAcquireParams {
  GstFormat                 format;
  gint64                    start;
  gint64                    stop;
  GstBufferPoolAcquireFlags flags;
};

Parameters passed to the gst_buffer_pool_acquire_buffer() function to control the allocation of the buffer.

The default implementation ignores the start and stop members but other implementations can use this extra information to decide what buffer to return.