1 /* GStreamer aggregator base class
2 * Copyright (C) 2014 Mathieu Duponchelle <mathieu.duponchelle@oencreed.com>
3 * Copyright (C) 2014 Thibault Saunier <tsaunier@gnome.org>
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
15 * You should have received a copy of the GNU Library General Public
16 * License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor,
18 * Boston, MA 02110-1301, USA.
21 #ifndef __GST_AGGREGATOR_H__
22 #define __GST_AGGREGATOR_H__
25 #include <gst/base/base-prelude.h>
29 /**************************
30 * GstAggregator Structs *
31 *************************/
33 typedef struct _GstAggregator GstAggregator;
34 typedef struct _GstAggregatorPrivate GstAggregatorPrivate;
35 typedef struct _GstAggregatorClass GstAggregatorClass;
37 /************************
38 * GstAggregatorPad API *
39 ***********************/
41 #define GST_TYPE_AGGREGATOR_PAD (gst_aggregator_pad_get_type())
42 #define GST_AGGREGATOR_PAD(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_AGGREGATOR_PAD, GstAggregatorPad))
43 #define GST_AGGREGATOR_PAD_CAST(obj) ((GstAggregatorPad *)(obj))
44 #define GST_AGGREGATOR_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_AGGREGATOR_PAD, GstAggregatorPadClass))
45 #define GST_AGGREGATOR_PAD_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj),GST_TYPE_AGGREGATOR_PAD, GstAggregatorPadClass))
46 #define GST_IS_AGGREGATOR_PAD(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_AGGREGATOR_PAD))
47 #define GST_IS_AGGREGATOR_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_AGGREGATOR_PAD))
49 /****************************
50 * GstAggregatorPad Structs *
51 ***************************/
53 typedef struct _GstAggregatorPad GstAggregatorPad;
54 typedef struct _GstAggregatorPadClass GstAggregatorPadClass;
55 typedef struct _GstAggregatorPadPrivate GstAggregatorPadPrivate;
59 * @segment: last segment received.
61 * The implementation the GstPad to use with #GstAggregator
65 struct _GstAggregatorPad
70 /* Protected by the OBJECT_LOCK */
74 GstAggregatorPadPrivate * priv;
76 gpointer _gst_reserved[GST_PADDING];
80 * GstAggregatorPadClass:
82 * Called when the pad has received a flush stop, this is the place
83 * to flush any information specific to the pad, it allows for individual
84 * pads to be flushed while others might not be.
85 * @skip_buffer: Optional
86 * Called before input buffers are queued in the pad, return %TRUE
87 * if the buffer should be skipped.
91 struct _GstAggregatorPadClass
93 GstPadClass parent_class;
95 GstFlowReturn (*flush) (GstAggregatorPad * aggpad, GstAggregator * aggregator);
96 gboolean (*skip_buffer) (GstAggregatorPad * aggpad, GstAggregator * aggregator, GstBuffer * buffer);
99 gpointer _gst_reserved[GST_PADDING_LARGE];
103 GType gst_aggregator_pad_get_type (void);
105 /****************************
106 * GstAggregatorPad methods *
107 ***************************/
110 GstBuffer * gst_aggregator_pad_pop_buffer (GstAggregatorPad * pad);
113 GstBuffer * gst_aggregator_pad_peek_buffer (GstAggregatorPad * pad);
116 gboolean gst_aggregator_pad_drop_buffer (GstAggregatorPad * pad);
119 gboolean gst_aggregator_pad_has_buffer (GstAggregatorPad * pad);
122 gboolean gst_aggregator_pad_is_eos (GstAggregatorPad * pad);
124 /*********************
125 * GstAggregator API *
126 ********************/
128 #define GST_TYPE_AGGREGATOR (gst_aggregator_get_type())
129 #define GST_AGGREGATOR(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_AGGREGATOR,GstAggregator))
130 #define GST_AGGREGATOR_CAST(obj) ((GstAggregator *)(obj))
131 #define GST_AGGREGATOR_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_AGGREGATOR,GstAggregatorClass))
132 #define GST_AGGREGATOR_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj),GST_TYPE_AGGREGATOR,GstAggregatorClass))
133 #define GST_IS_AGGREGATOR(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_AGGREGATOR))
134 #define GST_IS_AGGREGATOR_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_AGGREGATOR))
136 #define GST_AGGREGATOR_FLOW_NEED_DATA GST_FLOW_CUSTOM_ERROR
140 * @srcpad: the aggregator's source pad
142 * Aggregator base class object structure.
146 struct _GstAggregator
154 GstAggregatorPrivate * priv;
156 gpointer _gst_reserved[GST_PADDING_LARGE];
160 * GstAggregatorClass:
162 * Called after a successful flushing seek, once all the flush
163 * stops have been received. Flush pad-specific data in
164 * #GstAggregatorPad->flush.
166 * Called when a buffer is received on a sink pad, the task of
167 * clipping it and translating it to the current segment falls
168 * on the subclass. The function should use the segment of data
169 * and the negotiated media type on the pad to perform
170 * clipping of input buffer. This function takes ownership of
171 * buf and should output a buffer or return NULL in
172 * if the buffer should be dropped.
173 * @finish_buffer: Optional.
174 * Called when a subclass calls gst_aggregator_finish_buffer()
175 * from their aggregate function to push out a buffer.
176 * Subclasses can override this to modify or decorate buffers
177 * before they get pushed out. This function takes ownership
178 * of the buffer passed. Subclasses that override this method
179 * should always chain up to the parent class virtual method.
180 * @sink_event: Optional.
181 * Called when an event is received on a sink pad, the subclass
182 * should always chain up.
183 * @sink_query: Optional.
184 * Called when a query is received on a sink pad, the subclass
185 * should always chain up.
186 * @src_event: Optional.
187 * Called when an event is received on the src pad, the subclass
188 * should always chain up.
189 * @src_query: Optional.
190 * Called when a query is received on the src pad, the subclass
191 * should always chain up.
192 * @src_activate: Optional.
193 * Called when the src pad is activated, it will start/stop its
194 * pad task right after that call.
195 * @aggregate: Mandatory.
196 * Called when buffers are queued on all sinkpads. Classes
197 * should iterate the GstElement->sinkpads and peek or steal
198 * buffers from the #GstAggregatorPads. If the subclass returns
199 * GST_FLOW_EOS, sending of the eos event will be taken care
200 * of. Once / if a buffer has been constructed from the
201 * aggregated buffers, the subclass should call _finish_buffer.
203 * Called when the element goes from PAUSED to READY.
204 * The subclass should free all resources and reset its state.
206 * Called when the element goes from READY to PAUSED.
207 * The subclass should get ready to process
208 * aggregated buffers.
209 * @get_next_time: Optional.
210 * Called when the element needs to know the running time of the next
211 * rendered buffer for live pipelines. This causes deadline
212 * based aggregation to occur. Defaults to returning
213 * GST_CLOCK_TIME_NONE causing the element to wait for buffers
214 * on all sink pads before aggregating.
215 * @create_new_pad: Optional.
216 * Called when a new pad needs to be created. Allows subclass that
217 * don't have a single sink pad template to provide a pad based
218 * on the provided information.
219 * @update_src_caps: Lets subclasses update the #GstCaps representing
220 * the src pad caps before usage. The result should end up
221 * in @ret. Return %GST_AGGREGATOR_FLOW_NEED_DATA to indicate that the
222 * element needs more information (caps, a buffer, etc) to
223 * choose the correct caps. Should return ANY caps if the
224 * stream has not caps at all.
225 * @fixate_src_caps: Optional.
226 * Fixate and return the src pad caps provided. The function takes
227 * ownership of @caps and returns a fixated version of
228 * @caps. @caps is not guaranteed to be writable.
229 * @negotiated_src_caps: Optional.
230 * Notifies subclasses what caps format has been negotiated
231 * @decide_allocation: Optional.
232 * Allows the subclass to influence the allocation choices.
233 * Setup the allocation parameters for allocating output
234 * buffers. The passed in query contains the result of the
235 * downstream allocation query.
236 * @propose_allocation: Optional.
237 * Allows the subclass to handle the allocation query from upstream.
239 * The aggregator base class will handle in a thread-safe way all manners of
240 * concurrent flushes, seeks, pad additions and removals, leaving to the
241 * subclass the responsibility of clipping buffers, and aggregating buffers in
242 * the way the implementor sees fit.
244 * It will also take care of event ordering (stream-start, segment, eos).
246 * Basically, a simple implementation will override @aggregate, and call
247 * _finish_buffer from inside that function.
251 struct _GstAggregatorClass {
252 GstElementClass parent_class;
254 GstFlowReturn (*flush) (GstAggregator * aggregator);
256 GstBuffer * (*clip) (GstAggregator * aggregator,
257 GstAggregatorPad * aggregator_pad,
260 GstFlowReturn (*finish_buffer) (GstAggregator * aggregator,
263 /* sinkpads virtual methods */
264 gboolean (*sink_event) (GstAggregator * aggregator,
265 GstAggregatorPad * aggregator_pad,
268 gboolean (*sink_query) (GstAggregator * aggregator,
269 GstAggregatorPad * aggregator_pad,
272 /* srcpad virtual methods */
273 gboolean (*src_event) (GstAggregator * aggregator,
276 gboolean (*src_query) (GstAggregator * aggregator,
279 gboolean (*src_activate) (GstAggregator * aggregator,
283 GstFlowReturn (*aggregate) (GstAggregator * aggregator,
286 gboolean (*stop) (GstAggregator * aggregator);
288 gboolean (*start) (GstAggregator * aggregator);
290 GstClockTime (*get_next_time) (GstAggregator * aggregator);
292 GstAggregatorPad * (*create_new_pad) (GstAggregator * self,
293 GstPadTemplate * templ,
294 const gchar * req_name,
295 const GstCaps * caps);
298 * GstAggregatorClass::update_src_caps:
299 * @ret: (out) (allow-none):
301 GstFlowReturn (*update_src_caps) (GstAggregator * self,
304 GstCaps * (*fixate_src_caps) (GstAggregator * self,
306 gboolean (*negotiated_src_caps) (GstAggregator * self,
308 gboolean (*decide_allocation) (GstAggregator * self,
310 gboolean (*propose_allocation) (GstAggregator * self,
311 GstAggregatorPad * pad,
312 GstQuery * decide_query,
315 gpointer _gst_reserved[GST_PADDING_LARGE];
318 /************************************
319 * GstAggregator convenience macros *
320 ***********************************/
323 * GST_AGGREGATOR_SRC_PAD:
324 * @agg: a #GstAggregator
326 * Convenience macro to access the source pad of #GstAggregator
330 #define GST_AGGREGATOR_SRC_PAD(agg) (((GstAggregator *)(agg))->srcpad)
332 /*************************
333 * GstAggregator methods *
334 ************************/
337 GstFlowReturn gst_aggregator_finish_buffer (GstAggregator * aggregator,
341 void gst_aggregator_set_src_caps (GstAggregator * self,
345 void gst_aggregator_set_latency (GstAggregator * self,
346 GstClockTime min_latency,
347 GstClockTime max_latency);
350 GType gst_aggregator_get_type(void);
353 GstClockTime gst_aggregator_get_latency (GstAggregator * self);
356 GstBufferPool * gst_aggregator_get_buffer_pool (GstAggregator * self);
359 void gst_aggregator_get_allocator (GstAggregator * self,
360 GstAllocator ** allocator,
361 GstAllocationParams * params);
364 GstClockTime gst_aggregator_simple_get_next_time (GstAggregator * self);
369 #ifdef G_DEFINE_AUTOPTR_CLEANUP_FUNC
370 G_DEFINE_AUTOPTR_CLEANUP_FUNC(GstAggregator, gst_object_unref)
371 G_DEFINE_AUTOPTR_CLEANUP_FUNC(GstAggregatorPad, gst_object_unref)
374 #endif /* __GST_AGGREGATOR_H__ */