2 * Copyright (C) 2010 Wim Taymans <wim.taymans@gmail.com>
4 * gstbufferpool.h: Header for GstBufferPool object
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
16 * You should have received a copy of the GNU Library General Public
17 * License along with this library; if not, write to the
18 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 * Boston, MA 02111-1307, USA.
23 #ifndef __GST_BUFFER_POOL_H__
24 #define __GST_BUFFER_POOL_H__
26 #include <gst/gstminiobject.h>
27 #include <gst/gstatomicqueue.h>
28 #include <gst/gstpoll.h>
29 #include <gst/gstclock.h>
30 #include <gst/gstpad.h>
31 #include <gst/gstbuffer.h>
35 typedef struct _GstBufferPoolPrivate GstBufferPoolPrivate;
36 typedef struct _GstBufferPoolClass GstBufferPoolClass;
38 #define GST_TYPE_BUFFER_POOL (gst_buffer_pool_get_type())
39 #define GST_IS_BUFFER_POOL(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_BUFFER_POOL))
40 #define GST_IS_BUFFER_POOL_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_BUFFER_POOL))
41 #define GST_BUFFER_POOL_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_BUFFER_POOL, GstBufferPoolClass))
42 #define GST_BUFFER_POOL(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_BUFFER_POOL, GstBufferPool))
43 #define GST_BUFFER_POOL_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_BUFFER_POOL, GstBufferPoolClass))
44 #define GST_BUFFER_POOL_CAST(obj) ((GstBufferPool *)(obj))
48 * @GST_BUFFER_POOL_FLAG_NONE: no flags
49 * @GST_BUFFER_POOL_FLAG_KEY_UNIT: buffer is keyframe
50 * @GST_BUFFER_POOL_FLAG_DONTWAIT: don't wait for buffer. This makes the
51 * acquire_buffer method return GST_FLOW_UNEXPECTED.
52 * @GST_BUFFER_POOL_FLAG_DISCONT: buffer is discont
53 * @GST_BUFFER_POOL_FLAG_LAST: last flag, subclasses can use private flags
54 * starting from this value.
56 * Additional flags to control the allocation of a buffer
59 GST_BUFFER_POOL_FLAG_NONE = 0,
60 GST_BUFFER_POOL_FLAG_KEY_UNIT = (1 << 0),
61 GST_BUFFER_POOL_FLAG_DONTWAIT = (1 << 1),
62 GST_BUFFER_POOL_FLAG_DISCONT = (1 << 2),
63 GST_BUFFER_POOL_FLAG_LAST = (1 << 16),
67 * GstBufferPoolParams:
68 * @format: the format of @start and @stop
69 * @start: the start position
70 * @stop: the stop position
71 * @flags: additional flags
73 * Parameters passed to the gst_buffer_pool_acquire_buffer() function to control the
74 * allocation of the buffer.
76 * The default implementation ignores the @start and @stop members but other
77 * implementations can use this extra information to decide what buffer to
80 typedef struct _GstBufferPoolParams {
84 GstBufferPoolFlags flags;
87 gpointer _gst_reserved[GST_PADDING];
88 } GstBufferPoolParams;
91 * GST_BUFFER_POOL_IS_FLUSHING:
92 * @pool: a GstBufferPool
94 * Check if the bufferpool is flushing. Subclasses might want to check the
95 * state of the pool in the acquire function.
97 #define GST_BUFFER_POOL_IS_FLUSHING(pool) (g_atomic_int_get (&pool->flushing))
101 * @object: the parent structure
103 * The structure of a #GstBufferPool. Use the associated macros to access the public
106 struct _GstBufferPool {
114 GstAtomicQueue *queue;
118 GstStructure *config;
120 GstBufferPoolPrivate *priv;
122 gpointer _gst_reserved[GST_PADDING];
126 * GstBufferPoolClass:
127 * @object_class: Object parent class
128 * @get_options: get a list of options supported by this pool
129 * @set_config: apply the bufferpool configuration. The default configuration
130 * will parse the default config parameters
131 * @start: start the bufferpool. The default implementation will preallocate
132 * min-buffers buffers and put them in the queue
133 * @stop: stop the bufferpool. the default implementation will free the
134 * preallocated buffers. This function is called when all the buffers are
135 * returned to the pool.
136 * @acquire_buffer: get a new buffer from the pool. The default implementation
137 * will take a buffer from the queue and optionally wait for a buffer to
138 * be released when there are no buffers available.
139 * @alloc_buffer: allocate a buffer. the default implementation allocates
140 * buffers from the default memory allocator and with the configured
141 * size, prefix and alignment. All metadata that is present on the
142 * allocated buffer will be marked as #GST_META_FLAG_POOLED and will not
143 * be removed from the buffer in @reset_buffer.
144 * @reset_buffer: reset the buffer to its state when it was freshly allocated.
145 * The default implementation will clear the flags, timestamps and
146 * will remove the metadata added after alloc_buffer.
147 * @release_buffer: release a buffer back in the pool. The default
148 * implementation will put the buffer back in the queue and notify any
149 * blocking acquire_buffer calls.
150 * @free_buffer: free a buffer. The default implementation unrefs the buffer.
152 * The GstBufferPool class.
154 struct _GstBufferPoolClass {
155 GstObjectClass object_class;
158 const gchar ** (*get_options) (GstBufferPool *pool);
159 gboolean (*set_config) (GstBufferPool *pool, GstStructure *config);
161 gboolean (*start) (GstBufferPool *pool);
162 gboolean (*stop) (GstBufferPool *pool);
164 GstFlowReturn (*acquire_buffer) (GstBufferPool *pool, GstBuffer **buffer,
165 GstBufferPoolParams *params);
166 GstFlowReturn (*alloc_buffer) (GstBufferPool *pool, GstBuffer **buffer,
167 GstBufferPoolParams *params);
168 void (*reset_buffer) (GstBufferPool *pool, GstBuffer *buffer,
169 GstBufferPoolParams *params);
170 void (*release_buffer) (GstBufferPool *pool, GstBuffer *buffer);
171 void (*free_buffer) (GstBufferPool *pool, GstBuffer *buffer);
174 gpointer _gst_reserved[GST_PADDING];
177 GType gst_buffer_pool_get_type (void);
180 GstBufferPool * gst_buffer_pool_new (void);
182 /* state management */
183 gboolean gst_buffer_pool_set_active (GstBufferPool *pool, gboolean active);
184 gboolean gst_buffer_pool_is_active (GstBufferPool *pool);
186 gboolean gst_buffer_pool_set_config (GstBufferPool *pool, GstStructure *config);
187 GstStructure * gst_buffer_pool_get_config (GstBufferPool *pool);
189 const gchar ** gst_buffer_pool_get_options (GstBufferPool *pool);
190 gboolean gst_buffer_pool_has_option (GstBufferPool *pool, const gchar *option);
192 /* helpers for configuring the config structure */
193 void gst_buffer_pool_config_set (GstStructure *config, const GstCaps *caps,
194 guint size, guint min_buffers, guint max_buffers,
195 guint prefix, guint align);
196 gboolean gst_buffer_pool_config_get (GstStructure *config, const GstCaps **caps,
197 guint *size, guint *min_buffers, guint *max_buffers,
198 guint *prefix, guint *align);
201 guint gst_buffer_pool_config_n_options (GstStructure *config);
202 void gst_buffer_pool_config_add_option (GstStructure *config, const gchar *option);
203 const gchar * gst_buffer_pool_config_get_option (GstStructure *config, guint index);
204 gboolean gst_buffer_pool_config_has_option (GstStructure *config, const gchar *option);
206 /* buffer management */
207 GstFlowReturn gst_buffer_pool_acquire_buffer (GstBufferPool *pool, GstBuffer **buffer,
208 GstBufferPoolParams *params);
209 void gst_buffer_pool_release_buffer (GstBufferPool *pool, GstBuffer *buffer);
213 #endif /* __GST_BUFFER_POOL_H__ */