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__
24 #ifndef GST_USE_UNSTABLE_API
25 #warning "The Base library from gst-plugins-bad is unstable API and may change in future."
26 #warning "You can define GST_USE_UNSTABLE_API to avoid this warning."
33 /**************************
34 * GstAggregator Structs *
35 *************************/
37 typedef struct _GstAggregator GstAggregator;
38 typedef struct _GstAggregatorPrivate GstAggregatorPrivate;
39 typedef struct _GstAggregatorClass GstAggregatorClass;
41 /************************
42 * GstAggregatorPad API *
43 ***********************/
45 #define GST_TYPE_AGGREGATOR_PAD (gst_aggregator_pad_get_type())
46 #define GST_AGGREGATOR_PAD(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_AGGREGATOR_PAD, GstAggregatorPad))
47 #define GST_AGGREGATOR_PAD_CAST(obj) ((GstAggregatorPad *)(obj))
48 #define GST_AGGREGATOR_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_AGGREGATOR_PAD, GstAggregatorPadClass))
49 #define GST_AGGREGATOR_PAD_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj),GST_TYPE_AGGREGATOR_PAD, GstAggregatorPadClass))
50 #define GST_IS_AGGREGATOR_PAD(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_AGGREGATOR_PAD))
51 #define GST_IS_AGGREGATOR_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_AGGREGATOR_PAD))
53 /****************************
54 * GstAggregatorPad Structs *
55 ***************************/
57 typedef struct _GstAggregatorPad GstAggregatorPad;
58 typedef struct _GstAggregatorPadClass GstAggregatorPadClass;
59 typedef struct _GstAggregatorPadPrivate GstAggregatorPadPrivate;
63 * @buffer: currently queued buffer.
64 * @segment: last segment received.
66 * The implementation the GstPad to use with #GstAggregator
68 struct _GstAggregatorPad
72 /* Protected by the OBJECT_LOCK */
74 /* Segment to use in the clip function, before the queue */
75 GstSegment clip_segment;
78 GstAggregatorPadPrivate * priv;
80 gpointer _gst_reserved[GST_PADDING];
84 * GstAggregatorPadClass:
86 * Called when the pad has received a flush stop, this is the place
87 * to flush any information specific to the pad, it allows for individual
88 * pads to be flushed while others might not be.
91 struct _GstAggregatorPadClass
93 GstPadClass parent_class;
95 GstFlowReturn (*flush) (GstAggregatorPad * aggpad, GstAggregator * aggregator);
98 gpointer _gst_reserved[GST_PADDING_LARGE];
101 GType gst_aggregator_pad_get_type (void);
103 /****************************
104 * GstAggregatorPad methods *
105 ***************************/
107 GstBuffer * gst_aggregator_pad_steal_buffer (GstAggregatorPad * pad);
108 GstBuffer * gst_aggregator_pad_get_buffer (GstAggregatorPad * pad);
109 gboolean gst_aggregator_pad_drop_buffer (GstAggregatorPad * pad);
110 gboolean gst_aggregator_pad_is_eos (GstAggregatorPad * pad);
112 /*********************
113 * GstAggregator API *
114 ********************/
116 #define GST_TYPE_AGGREGATOR (gst_aggregator_get_type())
117 #define GST_AGGREGATOR(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_AGGREGATOR,GstAggregator))
118 #define GST_AGGREGATOR_CAST(obj) ((GstAggregator *)(obj))
119 #define GST_AGGREGATOR_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_AGGREGATOR,GstAggregatorClass))
120 #define GST_AGGREGATOR_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj),GST_TYPE_AGGREGATOR,GstAggregatorClass))
121 #define GST_IS_AGGREGATOR(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_AGGREGATOR))
122 #define GST_IS_AGGREGATOR_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_AGGREGATOR))
124 #define GST_FLOW_NOT_HANDLED GST_FLOW_CUSTOM_SUCCESS
128 * @srcpad: the aggregator's source pad
129 * @segment: the output segment
131 * Aggregator base class object structure.
133 struct _GstAggregator
139 /* Only access with the object lock held */
143 GstAggregatorPrivate * priv;
145 gpointer _gst_reserved[GST_PADDING_LARGE];
149 * GstAggregatorClass:
150 * @sinkpads_type: Optional.
151 * The type of the pads that should be created when
152 * GstElement.request_new_pad is called.
154 * Called after a succesful flushing seek, once all the flush
155 * stops have been received. Flush pad-specific data in
156 * #GstAggregatorPad->flush.
158 * Called when a buffer is received on a sink pad, the task
159 * of clipping it and translating it to the current segment
160 * falls on the subclass.
161 * @sink_event: Optional.
162 * Called when an event is received on a sink pad, the subclass
163 * should always chain up.
164 * @sink_query: Optional.
165 * Called when a query is received on a sink pad, the subclass
166 * should always chain up.
167 * @src_event: Optional.
168 * Called when an event is received on the src pad, the subclass
169 * should always chain up.
170 * @src_query: Optional.
171 * Called when a query is received on the src pad, the subclass
172 * should always chain up.
173 * @src_activate: Optional.
174 * Called when the src pad is activated, it will start/stop its
175 * pad task right after that call.
176 * @aggregate: Mandatory.
177 * Called when buffers are queued on all sinkpads. Classes
178 * should iterate the GstElement->sinkpads and peek or steal
179 * buffers from the #GstAggregatorPads. If the subclass returns
180 * GST_FLOW_EOS, sending of the eos event will be taken care
181 * of. Once / if a buffer has been constructed from the
182 * aggregated buffers, the subclass should call _finish_buffer.
184 * Called when the element goes from PAUSED to READY.
185 * The subclass should free all resources and reset its state.
187 * Called when the element goes from READY to PAUSED.
188 * The subclass should get ready to process
189 * aggregated buffers.
190 * @get_next_time: Optional.
191 * Called when the element needs to know the running time of the next
192 * rendered buffer for live pipelines. This causes deadline
193 * based aggregation to occur. Defaults to returning
194 * GST_CLOCK_TIME_NONE causing the element to wait for buffers
195 * on all sink pads before aggregating.
197 * The aggregator base class will handle in a thread-safe way all manners of
198 * concurrent flushes, seeks, pad additions and removals, leaving to the
199 * subclass the responsibility of clipping buffers, and aggregating buffers in
200 * the way the implementor sees fit.
202 * It will also take care of event ordering (stream-start, segment, eos).
204 * Basically, a basic implementation will override @aggregate, and call
205 * _finish_buffer from inside that function.
207 struct _GstAggregatorClass {
208 GstElementClass parent_class;
212 GstFlowReturn (*flush) (GstAggregator * aggregator);
214 GstFlowReturn (*clip) (GstAggregator * aggregator,
215 GstAggregatorPad * aggregator_pad,
217 GstBuffer ** outbuf);
219 /* sinkpads virtual methods */
220 gboolean (*sink_event) (GstAggregator * aggregator,
221 GstAggregatorPad * aggregator_pad,
224 gboolean (*sink_query) (GstAggregator * aggregator,
225 GstAggregatorPad * aggregator_pad,
228 /* srcpad virtual methods */
229 gboolean (*src_event) (GstAggregator * aggregator,
232 gboolean (*src_query) (GstAggregator * aggregator,
235 gboolean (*src_activate) (GstAggregator * aggregator,
239 GstFlowReturn (*aggregate) (GstAggregator * aggregator,
242 gboolean (*stop) (GstAggregator * aggregator);
244 gboolean (*start) (GstAggregator * aggregator);
246 GstClockTime (*get_next_time) (GstAggregator * aggregator);
248 GstAggregatorPad * (*create_new_pad) (GstAggregator * self,
249 GstPadTemplate * templ,
250 const gchar * req_name,
251 const GstCaps * caps);
254 gpointer _gst_reserved[GST_PADDING_LARGE];
257 /************************************
258 * GstAggregator convenience macros *
259 ***********************************/
262 * GST_AGGREGATOR_SRC_PAD:
263 * @agg: a #GstAggregator
265 * Convenience macro to access the source pad of #GstAggregator
269 #define GST_AGGREGATOR_SRC_PAD(agg) (((GstAggregator *)(agg))->srcpad)
271 /*************************
272 * GstAggregator methods *
273 ************************/
275 GstFlowReturn gst_aggregator_finish_buffer (GstAggregator * agg,
277 void gst_aggregator_set_src_caps (GstAggregator * agg,
280 void gst_aggregator_set_latency (GstAggregator * self,
281 GstClockTime min_latency,
282 GstClockTime max_latency);
284 GType gst_aggregator_get_type(void);
286 /* API that should eventually land in GstElement itself (FIXME) */
287 typedef gboolean (*GstAggregatorPadForeachFunc) (GstAggregator * aggregator,
288 GstAggregatorPad * aggregator_pad,
291 gboolean gst_aggregator_iterate_sinkpads (GstAggregator * self,
292 GstAggregatorPadForeachFunc func,
295 GstClockTime gst_aggregator_get_latency (GstAggregator * self);
299 #endif /* __GST_AGGREGATOR_H__ */