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;
39 * GST_BUFFER_POOL_TRACE_NAME:
41 * The name used for tracing memory allocations.
43 #define GST_BUFFER_POOL_TRACE_NAME "GstBufferPool"
45 #define GST_TYPE_BUFFER_POOL (gst_buffer_pool_get_type())
46 #define GST_IS_BUFFER_POOL(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_BUFFER_POOL))
47 #define GST_IS_BUFFER_POOL_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_BUFFER_POOL))
48 #define GST_BUFFER_POOL_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_BUFFER_POOL, GstBufferPoolClass))
49 #define GST_BUFFER_POOL(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_BUFFER_POOL, GstBufferPool))
50 #define GST_BUFFER_POOL_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_BUFFER_POOL, GstBufferPoolClass))
51 #define GST_BUFFER_POOL_CAST(obj) ((GstBufferPool *)(obj))
55 * @GST_BUFFER_POOL_FLAG_NONE: no flags
56 * @GST_BUFFER_POOL_FLAG_KEY_UNIT: buffer is keyframe
57 * @GST_BUFFER_POOL_FLAG_DONTWAIT: don't wait for buffer. This makes the
58 * acquire_buffer method return GST_FLOW_UNEXPECTED.
59 * @GST_BUFFER_POOL_FLAG_DISCONT: buffer is discont
60 * @GST_BUFFER_POOL_FLAG_LAST: last flag, subclasses can use private flags
61 * starting from this value.
63 * Additional flags to control the allocation of a buffer
66 GST_BUFFER_POOL_FLAG_NONE = 0,
67 GST_BUFFER_POOL_FLAG_KEY_UNIT = (1 << 0),
68 GST_BUFFER_POOL_FLAG_DONTWAIT = (1 << 1),
69 GST_BUFFER_POOL_FLAG_DISCONT = (1 << 2),
70 GST_BUFFER_POOL_FLAG_LAST = (1 << 16),
74 * GstBufferPoolParams:
75 * @format: the format of @start and @stop
76 * @start: the start position
77 * @stop: the stop position
78 * @flags: additional flags
80 * Parameters passed to the gst_buffer_pool_acquire_buffer() function to control the
81 * allocation of the buffer.
83 * The default implementation ignores the @start and @stop members but other
84 * implementations can use this extra information to decide what buffer to
87 typedef struct _GstBufferPoolParams {
91 GstBufferPoolFlags flags;
94 gpointer _gst_reserved[GST_PADDING];
95 } GstBufferPoolParams;
98 * GST_BUFFER_POOL_IS_FLUSHING:
99 * @pool: a GstBufferPool
101 * Check if the bufferpool is flushing. Subclasses might want to check the
102 * state of the pool in the acquire function.
104 #define GST_BUFFER_POOL_IS_FLUSHING(pool) (g_atomic_int_get (&pool->flushing))
108 * @object: the parent structure
110 * The structure of a #GstBufferPool. Use the associated macros to access the public
113 struct _GstBufferPool {
121 GstAtomicQueue *queue;
125 GstStructure *config;
127 GstBufferPoolPrivate *priv;
129 gpointer _gst_reserved[GST_PADDING];
133 * GstBufferPoolClass:
134 * @object_class: Object parent class
135 * @get_options: get a list of options supported by this pool
136 * @set_config: apply the bufferpool configuration. The default configuration
137 * will parse the default config parameters
138 * @start: start the bufferpool. The default implementation will preallocate
139 * min-buffers buffers and put them in the queue
140 * @stop: stop the bufferpool. the default implementation will free the
141 * preallocated buffers. This function is called when all the buffers are
142 * returned to the pool.
143 * @acquire_buffer: get a new buffer from the pool. The default implementation
144 * will take a buffer from the queue and optionally wait for a buffer to
145 * be released when there are no buffers available.
146 * @alloc_buffer: allocate a buffer. the default implementation allocates
147 * buffers from the default memory allocator and with the configured
148 * size, prefix and alignment.
149 * @reset_buffer: reset the buffer to its state when it was freshly allocated.
150 * The default implementation will clear the flags and timestamps.
151 * @release_buffer: release a buffer back in the pool. The default
152 * implementation will put the buffer back in the queue and notify any
153 * blocking acquire_buffer calls.
154 * @free_buffer: free a buffer. The default implementation unrefs the buffer.
156 * The GstBufferPool class.
158 struct _GstBufferPoolClass {
159 GstObjectClass object_class;
162 const gchar ** (*get_options) (GstBufferPool *pool);
163 gboolean (*set_config) (GstBufferPool *pool, GstStructure *config);
165 gboolean (*start) (GstBufferPool *pool);
166 gboolean (*stop) (GstBufferPool *pool);
168 GstFlowReturn (*acquire_buffer) (GstBufferPool *pool, GstBuffer **buffer,
169 GstBufferPoolParams *params);
170 GstFlowReturn (*alloc_buffer) (GstBufferPool *pool, GstBuffer **buffer,
171 GstBufferPoolParams *params);
172 void (*reset_buffer) (GstBufferPool *pool, GstBuffer *buffer,
173 GstBufferPoolParams *params);
174 void (*release_buffer) (GstBufferPool *pool, GstBuffer *buffer);
175 void (*free_buffer) (GstBufferPool *pool, GstBuffer *buffer);
178 gpointer _gst_reserved[GST_PADDING];
181 GType gst_buffer_pool_get_type (void);
184 GstBufferPool * gst_buffer_pool_new (void);
186 /* state management */
187 gboolean gst_buffer_pool_set_active (GstBufferPool *pool, gboolean active);
188 gboolean gst_buffer_pool_is_active (GstBufferPool *pool);
190 gboolean gst_buffer_pool_set_config (GstBufferPool *pool, GstStructure *config);
191 GstStructure * gst_buffer_pool_get_config (GstBufferPool *pool);
193 const gchar ** gst_buffer_pool_get_options (GstBufferPool *pool);
194 gboolean gst_buffer_pool_has_option (GstBufferPool *pool, const gchar *option);
196 /* helpers for configuring the config structure */
197 void gst_buffer_pool_config_set (GstStructure *config, const GstCaps *caps,
198 guint size, guint min_buffers, guint max_buffers,
199 guint prefix, guint align);
200 gboolean gst_buffer_pool_config_get (GstStructure *config, const GstCaps **caps,
201 guint *size, guint *min_buffers, guint *max_buffers,
202 guint *prefix, guint *align);
205 guint gst_buffer_pool_config_n_options (GstStructure *config);
206 void gst_buffer_pool_config_add_option (GstStructure *config, const gchar *option);
207 const gchar * gst_buffer_pool_config_get_option (GstStructure *config, guint index);
208 gboolean gst_buffer_pool_config_has_option (GstStructure *config, const gchar *option);
210 /* buffer management */
211 GstFlowReturn gst_buffer_pool_acquire_buffer (GstBufferPool *pool, GstBuffer **buffer,
212 GstBufferPoolParams *params);
213 void gst_buffer_pool_release_buffer (GstBufferPool *pool, GstBuffer *buffer);
217 #endif /* __GST_BUFFER_POOL_H__ */