/* GStreamer
* Copyright (C) 2010 Wim Taymans <wim.taymans@gmail.com>
*
* gstbufferpool.h: Header for GstBufferPool object
*
* 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., 51 Franklin St, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#ifndef __GST_BUFFER_POOL_H__
#define __GST_BUFFER_POOL_H__
#include <gst/gstminiobject.h>
#include <gst/gstpad.h>
#include <gst/gstbuffer.h>
G_BEGIN_DECLS
typedef struct _GstBufferPoolPrivate GstBufferPoolPrivate;
typedef struct _GstBufferPoolClass GstBufferPoolClass;
#define GST_TYPE_BUFFER_POOL (gst_buffer_pool_get_type())
#define GST_IS_BUFFER_POOL(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_BUFFER_POOL))
#define GST_IS_BUFFER_POOL_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_BUFFER_POOL))
#define GST_BUFFER_POOL_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_BUFFER_POOL, GstBufferPoolClass))
#define GST_BUFFER_POOL(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_BUFFER_POOL, GstBufferPool))
#define GST_BUFFER_POOL_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_BUFFER_POOL, GstBufferPoolClass))
#define GST_BUFFER_POOL_CAST(obj) ((GstBufferPool *)(obj))
/**
* GstBufferPoolAcquireFlags:
* @GST_BUFFER_POOL_ACQUIRE_FLAG_NONE: no flags
* @GST_BUFFER_POOL_ACQUIRE_FLAG_KEY_UNIT: buffer is keyframe
* @GST_BUFFER_POOL_ACQUIRE_FLAG_DONTWAIT: when the bufferpool is empty, acquire_buffer
* will by default block until a buffer is released into the pool again. Setting
* this flag makes acquire_buffer return #GST_FLOW_EOS instead of blocking.
* @GST_BUFFER_POOL_ACQUIRE_FLAG_DISCONT: buffer is discont
* @GST_BUFFER_POOL_ACQUIRE_FLAG_LAST: last flag, subclasses can use private flags
* starting from this value.
*
* Additional flags to control the allocation of a buffer
*/
typedef enum {
GST_BUFFER_POOL_ACQUIRE_FLAG_NONE = 0,
GST_BUFFER_POOL_ACQUIRE_FLAG_KEY_UNIT = (1 << 0),
GST_BUFFER_POOL_ACQUIRE_FLAG_DONTWAIT = (1 << 1),
GST_BUFFER_POOL_ACQUIRE_FLAG_DISCONT = (1 << 2),
GST_BUFFER_POOL_ACQUIRE_FLAG_LAST = (1 << 16),
} GstBufferPoolAcquireFlags;
typedef struct _GstBufferPoolAcquireParams GstBufferPoolAcquireParams;
/**
* GstBufferPoolAcquireParams:
* @format: the format of @start and @stop
* @start: the start position
* @stop: the stop position
* @flags: additional 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.
*/
struct _GstBufferPoolAcquireParams {
GstFormat format;
gint64 start;
gint64 stop;
GstBufferPoolAcquireFlags flags;
/*< private >*/
gpointer _gst_reserved[GST_PADDING];
};
/**
* GST_BUFFER_POOL_IS_FLUSHING:
* @pool: a GstBufferPool
*
* Check if the bufferpool is flushing. Subclasses might want to check the
* state of the pool in the acquire function.
*/
#define GST_BUFFER_POOL_IS_FLUSHING(pool) (g_atomic_int_get (&pool->flushing))
/**
* GstBufferPool:
* @object: the parent structure
* @flushing: whether the pool is currently gathering back outstanding buffers
*
* The structure of a #GstBufferPool. Use the associated macros to access the public
* variables.
*/
struct _GstBufferPool {
GstObject object;
/*< protected >*/
gint flushing;
/*< private >*/
GstBufferPoolPrivate *priv;
gpointer _gst_reserved[GST_PADDING];
};
/**
* GstBufferPoolClass:
* @object_class: Object parent class
*
* The #GstBufferPool class.
*/
struct _GstBufferPoolClass {
GstObjectClass object_class;
/*< public >*/
/**
* GstBufferPoolClass::get_options:
* @pool: the #GstBufferPool
*
* Get a list of options supported by this pool
*
* Returns: (array zero-terminated=1) (transfer none): a %NULL terminated array
* of strings.
*/
const gchar ** (*get_options) (GstBufferPool *pool);
/**
* GstBufferPoolClass::set_config:
* @pool: the #GstBufferPool
* @config: the required configuration
*
* Apply the bufferpool configuration. The default configuration will parse
* the default config parameters.
*
* Returns: whether the configuration could be set.
*/
gboolean (*set_config) (GstBufferPool *pool, GstStructure *config);
/**
* GstBufferPoolClass::start:
* @pool: the #GstBufferPool
*
* Start the bufferpool. The default implementation will preallocate
* min-buffers buffers and put them in the queue.
*
* Returns: whether the pool could be started.
*/
gboolean (*start) (GstBufferPool *pool);
/**
* GstBufferPoolClass::stop:
* @pool: the #GstBufferPool
*
* Stop the bufferpool. the default implementation will free the
* preallocated buffers. This function is called when all the buffers are
* returned to the pool.
*
* Returns: whether the pool could be stopped.
*/
gboolean (*stop) (GstBufferPool *pool);
/**
* GstBufferPoolClass::acquire_buffer:
* @pool: the #GstBufferPool
* @buffer: (out): a location for a #GstBuffer
* @params: (transfer none) (allow-none): parameters.
*
* Get a new buffer from the pool. The default implementation
* will take a buffer from the queue and optionally wait for a buffer to
* be released when there are no buffers available.
*
* Returns: a #GstFlowReturn such as %GST_FLOW_FLUSHING when the pool is
* inactive.
*/
GstFlowReturn (*acquire_buffer) (GstBufferPool *pool, GstBuffer **buffer,
GstBufferPoolAcquireParams *params);
/**
* GstBufferPoolClass::alloc_buffer:
* @pool: the #GstBufferPool
* @buffer: (out): a location for a #GstBuffer
* @params: (transfer none) (allow-none): parameters.
*
* Allocate a buffer. the default implementation allocates
* buffers from the configured memory allocator and with the configured
* parameters. All metadata that is present on the allocated buffer will
* be marked as #GST_META_FLAG_POOLED and #GST_META_FLAG_LOCKED and will
* not be removed from the buffer in #GstBufferPoolClass::reset_buffer.
* The buffer should have the #GST_BUFFER_FLAG_TAG_MEMORY cleared.
*
* Returns: a #GstFlowReturn to indicate whether the allocation was
* successful.
*/
GstFlowReturn (*alloc_buffer) (GstBufferPool *pool, GstBuffer **buffer,
GstBufferPoolAcquireParams *params);
/**
* GstBufferPoolClass::reset_buffer:
* @pool: the #GstBufferPool
* @buffer: the #GstBuffer to reset
*
* Reset the buffer to its state when it was freshly allocated.
* The default implementation will clear the flags, timestamps and
* will remove the metadata without the #GST_META_FLAG_POOLED flag (even
* the metadata with #GST_META_FLAG_LOCKED). If the
* #GST_BUFFER_FLAG_TAG_MEMORY was set, this function can also try to
* restore the memory and clear the #GST_BUFFER_FLAG_TAG_MEMORY again.
*/
void (*reset_buffer) (GstBufferPool *pool, GstBuffer *buffer);
/**
* GstBufferPoolClass::release_buffer:
* @pool: the #GstBufferPool
* @buffer: the #GstBuffer to release
*
* Release a buffer back in the pool. The default implementation
* will put the buffer back in the queue and notify any
* blocking #GstBufferPoolClass::acquire_buffer calls when the
* #GST_BUFFER_FLAG_TAG_MEMORY is not set on the buffer.
* If #GST_BUFFER_FLAG_TAG_MEMORY is set, the buffer will be freed with
* #GstBufferPoolClass::free_buffer.
*/
void (*release_buffer) (GstBufferPool *pool, GstBuffer *buffer);
/**
* GstBufferPoolClass::free_buffer:
* @pool: the #GstBufferPool
* @buffer: the #GstBuffer to free
*
* Free a buffer. The default implementation unrefs the buffer.
*/
void (*free_buffer) (GstBufferPool *pool, GstBuffer *buffer);
/**
* GstBufferPoolClass::flush_start:
* @pool: the #GstBufferPool
*
* Enter the flushing state.
*
* Since: 1.4
*/
void (*flush_start) (GstBufferPool *pool);
/**
* GstBufferPoolClass::flush_stop:
* @pool: the #GstBufferPool
*
* Leave the flushing state.
*
* Since: 1.4
*/
void (*flush_stop) (GstBufferPool *pool);
/*< private >*/
gpointer _gst_reserved[GST_PADDING - 2];
};
GST_API
GType gst_buffer_pool_get_type (void);
/* allocation */
GST_API
GstBufferPool * gst_buffer_pool_new (void);
/* state management */
GST_API
gboolean gst_buffer_pool_set_active (GstBufferPool *pool, gboolean active);
GST_API
gboolean gst_buffer_pool_is_active (GstBufferPool *pool);
GST_API
gboolean gst_buffer_pool_set_config (GstBufferPool *pool, GstStructure *config);
GST_API
GstStructure * gst_buffer_pool_get_config (GstBufferPool *pool);
GST_API
const gchar ** gst_buffer_pool_get_options (GstBufferPool *pool);
GST_API
gboolean gst_buffer_pool_has_option (GstBufferPool *pool, const gchar *option);
GST_API
void gst_buffer_pool_set_flushing (GstBufferPool *pool, gboolean flushing);
/* helpers for configuring the config structure */
GST_API
void gst_buffer_pool_config_set_params (GstStructure *config, GstCaps *caps,
guint size, guint min_buffers, guint max_buffers);
GST_API
gboolean gst_buffer_pool_config_get_params (GstStructure *config, GstCaps **caps,
guint *size, guint *min_buffers, guint *max_buffers);
GST_API
void gst_buffer_pool_config_set_allocator (GstStructure *config, GstAllocator *allocator,
const GstAllocationParams *params);
GST_API
gboolean gst_buffer_pool_config_get_allocator (GstStructure *config, GstAllocator **allocator,
GstAllocationParams *params);
/* options */
GST_API
guint gst_buffer_pool_config_n_options (GstStructure *config);
GST_API
void gst_buffer_pool_config_add_option (GstStructure *config, const gchar *option);
GST_API
const gchar * gst_buffer_pool_config_get_option (GstStructure *config, guint index);
GST_API
gboolean gst_buffer_pool_config_has_option (GstStructure *config, const gchar *option);
GST_API
gboolean gst_buffer_pool_config_validate_params (GstStructure *config, GstCaps *caps,
guint size, guint min_buffers, guint max_buffers);
/* buffer management */
GST_API
GstFlowReturn gst_buffer_pool_acquire_buffer (GstBufferPool *pool, GstBuffer **buffer,
GstBufferPoolAcquireParams *params);
GST_API
void gst_buffer_pool_release_buffer (GstBufferPool *pool, GstBuffer *buffer);
G_END_DECLS
#endif /* __GST_BUFFER_POOL_H__ */