• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /* GStreamer aggregator base class
2  * Copyright (C) 2014 Mathieu Duponchelle <mathieu.duponchelle@oencreed.com>
3  * Copyright (C) 2014 Thibault Saunier <tsaunier@gnome.org>
4  *
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.
9  *
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.
14  *
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.
19  */
20 
21 #ifndef __GST_AGGREGATOR_H__
22 #define __GST_AGGREGATOR_H__
23 
24 #include <gst/gst.h>
25 #include <gst/base/base-prelude.h>
26 
27 G_BEGIN_DECLS
28 
29 /**************************
30  * GstAggregator Structs  *
31  *************************/
32 
33 typedef struct _GstAggregator GstAggregator;
34 typedef struct _GstAggregatorPrivate GstAggregatorPrivate;
35 typedef struct _GstAggregatorClass GstAggregatorClass;
36 
37 /************************
38  * GstAggregatorPad API *
39  ***********************/
40 
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))
48 
49 /****************************
50  * GstAggregatorPad Structs *
51  ***************************/
52 
53 typedef struct _GstAggregatorPad GstAggregatorPad;
54 typedef struct _GstAggregatorPadClass GstAggregatorPadClass;
55 typedef struct _GstAggregatorPadPrivate GstAggregatorPadPrivate;
56 
57 /**
58  * GstAggregatorPad:
59  * @segment: last segment received.
60  *
61  * The implementation the GstPad to use with #GstAggregator
62  *
63  * Since: 1.14
64  */
65 struct _GstAggregatorPad
66 {
67   GstPad                       parent;
68 
69   /*< public >*/
70   /* Protected by the OBJECT_LOCK */
71   GstSegment segment;
72 
73   /* < private > */
74   GstAggregatorPadPrivate   *  priv;
75 
76   gpointer _gst_reserved[GST_PADDING];
77 };
78 
79 /**
80  * GstAggregatorPadClass:
81  * @flush:       Optional
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.
88  *
89  * Since: 1.14
90  */
91 struct _GstAggregatorPadClass
92 {
93   GstPadClass   parent_class;
94 
95   GstFlowReturn (*flush)       (GstAggregatorPad * aggpad, GstAggregator * aggregator);
96   gboolean      (*skip_buffer) (GstAggregatorPad * aggpad, GstAggregator * aggregator, GstBuffer * buffer);
97 
98   /*< private >*/
99   gpointer      _gst_reserved[GST_PADDING_LARGE];
100 };
101 
102 GST_BASE_API
103 GType gst_aggregator_pad_get_type           (void);
104 
105 /****************************
106  * GstAggregatorPad methods *
107  ***************************/
108 
109 GST_BASE_API
110 GstBuffer * gst_aggregator_pad_pop_buffer   (GstAggregatorPad *  pad);
111 
112 GST_BASE_API
113 GstBuffer * gst_aggregator_pad_peek_buffer  (GstAggregatorPad *  pad);
114 
115 GST_BASE_API
116 gboolean    gst_aggregator_pad_drop_buffer  (GstAggregatorPad *  pad);
117 
118 GST_BASE_API
119 gboolean    gst_aggregator_pad_has_buffer   (GstAggregatorPad * pad);
120 
121 GST_BASE_API
122 gboolean    gst_aggregator_pad_is_eos       (GstAggregatorPad *  pad);
123 
124 GST_BASE_API
125 gboolean    gst_aggregator_pad_is_inactive  (GstAggregatorPad * pad);
126 
127 /*********************
128  * GstAggregator API *
129  ********************/
130 
131 #define GST_TYPE_AGGREGATOR            (gst_aggregator_get_type())
132 #define GST_AGGREGATOR(obj)            (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_AGGREGATOR,GstAggregator))
133 #define GST_AGGREGATOR_CAST(obj)       ((GstAggregator *)(obj))
134 #define GST_AGGREGATOR_CLASS(klass)    (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_AGGREGATOR,GstAggregatorClass))
135 #define GST_AGGREGATOR_GET_CLASS(obj)  (G_TYPE_INSTANCE_GET_CLASS ((obj),GST_TYPE_AGGREGATOR,GstAggregatorClass))
136 #define GST_IS_AGGREGATOR(obj)         (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_AGGREGATOR))
137 #define GST_IS_AGGREGATOR_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_AGGREGATOR))
138 
139 #define GST_AGGREGATOR_FLOW_NEED_DATA             GST_FLOW_CUSTOM_ERROR
140 
141 /**
142  * GstAggregator:
143  * @srcpad: the aggregator's source pad
144  *
145  * Aggregator base class object structure.
146  *
147  * Since: 1.14
148  */
149 struct _GstAggregator
150 {
151   GstElement               parent;
152 
153   /*< public >*/
154   GstPad                *  srcpad;
155 
156   /*< private >*/
157   GstAggregatorPrivate  *  priv;
158 
159   gpointer                 _gst_reserved[GST_PADDING_LARGE];
160 };
161 
162 /**
163  * GstAggregatorClass:
164  * @flush:          Optional.
165  *                  Called after a successful flushing seek, once all the flush
166  *                  stops have been received. Flush pad-specific data in
167  *                  #GstAggregatorPad->flush.
168  * @clip:           Optional.
169  *                  Called when a buffer is received on a sink pad, the task of
170  *                  clipping it and translating it to the current segment falls
171  *                  on the subclass. The function should use the segment of data
172  *                  and the negotiated media type on the pad to perform
173  *                  clipping of input buffer. This function takes ownership of
174  *                  buf and should output a buffer or return NULL in
175  *                  if the buffer should be dropped.
176  * @finish_buffer:  Optional.
177  *                  Called when a subclass calls gst_aggregator_finish_buffer()
178  *                  from their aggregate function to push out a buffer.
179  *                  Subclasses can override this to modify or decorate buffers
180  *                  before they get pushed out. This function takes ownership
181  *                  of the buffer passed. Subclasses that override this method
182  *                  should always chain up to the parent class virtual method.
183  * @sink_event:     Optional.
184  *                  Called when an event is received on a sink pad, the subclass
185  *                  should always chain up.
186  * @sink_query:     Optional.
187  *                  Called when a query is received on a sink pad, the subclass
188  *                  should always chain up.
189  * @src_event:      Optional.
190  *                  Called when an event is received on the src pad, the subclass
191  *                  should always chain up.
192  * @src_query:      Optional.
193  *                  Called when a query is received on the src pad, the subclass
194  *                  should always chain up.
195  * @src_activate:   Optional.
196  *                  Called when the src pad is activated, it will start/stop its
197  *                  pad task right after that call.
198  * @aggregate:      Mandatory.
199  *                  Called when buffers are queued on all sinkpads. Classes
200  *                  should iterate the GstElement->sinkpads and peek or steal
201  *                  buffers from the #GstAggregatorPads. If the subclass returns
202  *                  GST_FLOW_EOS, sending of the eos event will be taken care
203  *                  of. Once / if a buffer has been constructed from the
204  *                  aggregated buffers, the subclass should call _finish_buffer.
205  * @stop:           Optional.
206  *                  Called when the element goes from PAUSED to READY.
207  *                  The subclass should free all resources and reset its state.
208  * @start:          Optional.
209  *                  Called when the element goes from READY to PAUSED.
210  *                  The subclass should get ready to process
211  *                  aggregated buffers.
212  * @get_next_time:  Optional.
213  *                  Called when the element needs to know the running time of the next
214  *                  rendered buffer for live pipelines. This causes deadline
215  *                  based aggregation to occur. Defaults to returning
216  *                  GST_CLOCK_TIME_NONE causing the element to wait for buffers
217  *                  on all sink pads before aggregating.
218  * @create_new_pad: Optional.
219  *                  Called when a new pad needs to be created. Allows subclass that
220  *                  don't have a single sink pad template to provide a pad based
221  *                  on the provided information.
222  * @update_src_caps: Lets subclasses update the #GstCaps representing
223  *                   the src pad caps before usage.  The result should end up
224  *                   in @ret. Return %GST_AGGREGATOR_FLOW_NEED_DATA to indicate that the
225  *                   element needs more information (caps, a buffer, etc) to
226  *                   choose the correct caps. Should return ANY caps if the
227  *                   stream has not caps at all.
228  * @fixate_src_caps: Optional.
229  *                   Fixate and return the src pad caps provided.  The function takes
230  *                   ownership of @caps and returns a fixated version of
231  *                   @caps. @caps is not guaranteed to be writable.
232  * @negotiated_src_caps: Optional.
233  *                       Notifies subclasses what caps format has been negotiated
234  * @decide_allocation: Optional.
235  *                     Allows the subclass to influence the allocation choices.
236  *                     Setup the allocation parameters for allocating output
237  *                     buffers. The passed in query contains the result of the
238  *                     downstream allocation query.
239  * @propose_allocation: Optional.
240  *                     Allows the subclass to handle the allocation query from upstream.
241  * @negotiate: Optional.
242  *             Negotiate the caps with the peer (Since: 1.18).
243  * @sink_event_pre_queue: Optional.
244  *                        Called when an event is received on a sink pad before queueing up
245  *                        serialized events. The subclass should always chain up (Since: 1.18).
246  * @sink_query_pre_queue: Optional.
247  *                        Called when a query is received on a sink pad before queueing up
248  *                        serialized queries. The subclass should always chain up (Since: 1.18).
249  *
250  * The aggregator base class will handle in a thread-safe way all manners of
251  * concurrent flushes, seeks, pad additions and removals, leaving to the
252  * subclass the responsibility of clipping buffers, and aggregating buffers in
253  * the way the implementor sees fit.
254  *
255  * It will also take care of event ordering (stream-start, segment, eos).
256  *
257  * Basically, a simple implementation will override @aggregate, and call
258  * _finish_buffer from inside that function.
259  *
260  * Since: 1.14
261  */
262 struct _GstAggregatorClass {
263   GstElementClass   parent_class;
264 
265   GstFlowReturn     (*flush)          (GstAggregator    *  aggregator);
266 
267   GstBuffer *       (*clip)           (GstAggregator    *  aggregator,
268                                        GstAggregatorPad *  aggregator_pad,
269                                        GstBuffer        *  buf);
270 
271   GstFlowReturn     (*finish_buffer)  (GstAggregator    * aggregator,
272                                        GstBuffer        * buffer);
273 
274   /* sinkpads virtual methods */
275   gboolean          (*sink_event)     (GstAggregator    *  aggregator,
276                                        GstAggregatorPad *  aggregator_pad,
277                                        GstEvent         *  event);
278 
279   gboolean          (*sink_query)     (GstAggregator    *  aggregator,
280                                        GstAggregatorPad *  aggregator_pad,
281                                        GstQuery         *  query);
282 
283   /* srcpad virtual methods */
284   gboolean          (*src_event)      (GstAggregator    *  aggregator,
285                                        GstEvent         *  event);
286 
287   gboolean          (*src_query)      (GstAggregator    *  aggregator,
288                                        GstQuery         *  query);
289 
290   gboolean          (*src_activate)   (GstAggregator    *  aggregator,
291                                        GstPadMode          mode,
292                                        gboolean            active);
293 
294   GstFlowReturn     (*aggregate)      (GstAggregator    *  aggregator,
295                                        gboolean            timeout);
296 
297   gboolean          (*stop)           (GstAggregator    *  aggregator);
298 
299   gboolean          (*start)          (GstAggregator    *  aggregator);
300 
301   GstClockTime      (*get_next_time)  (GstAggregator    *  aggregator);
302 
303   GstAggregatorPad * (*create_new_pad) (GstAggregator  * self,
304                                         GstPadTemplate * templ,
305                                         const gchar    * req_name,
306                                         const GstCaps  * caps);
307 
308   /**
309    * GstAggregatorClass::update_src_caps:
310    * @ret: (out) (allow-none):
311    */
312   GstFlowReturn     (*update_src_caps) (GstAggregator *  self,
313                                         GstCaps       *  caps,
314                                         GstCaps       ** ret);
315   GstCaps *         (*fixate_src_caps) (GstAggregator *  self,
316                                         GstCaps       *  caps);
317   gboolean          (*negotiated_src_caps) (GstAggregator *  self,
318                                             GstCaps      *  caps);
319   gboolean          (*decide_allocation) (GstAggregator * self,
320                                           GstQuery * query);
321   gboolean          (*propose_allocation) (GstAggregator * self,
322                                            GstAggregatorPad * pad,
323                                            GstQuery * decide_query,
324                                            GstQuery * query);
325 
326   gboolean          (*negotiate) (GstAggregator * self);
327 
328   GstFlowReturn     (*sink_event_pre_queue)     (GstAggregator    *  aggregator,
329                                                  GstAggregatorPad *  aggregator_pad,
330                                                  GstEvent         *  event);
331 
332   gboolean          (*sink_query_pre_queue)     (GstAggregator    *  aggregator,
333                                                  GstAggregatorPad *  aggregator_pad,
334                                                  GstQuery         *  query);
335 
336   /**
337    * GstAggregatorClass::finish_buffer_list:
338    *
339    * Optional. Equivalent of #GstAggregatorClass::finish_buffer for
340    * buffer lists.
341    *
342    * Since: 1.18
343    */
344   GstFlowReturn     (*finish_buffer_list) (GstAggregator    * aggregator,
345                                            GstBufferList    * bufferlist);
346   /**
347    * GstAggregatorClass::peek_next_sample:
348    *
349    * See gst_aggregator_peek_next_sample().
350    *
351    * Since: 1.18
352    */
353   GstSample *       (*peek_next_sample)         (GstAggregator *aggregator,
354                                                  GstAggregatorPad * aggregator_pad);
355 
356   /*< private >*/
357   gpointer          _gst_reserved[GST_PADDING_LARGE-5];
358 };
359 
360 /************************************
361  * GstAggregator convenience macros *
362  ***********************************/
363 
364 /**
365  * GST_AGGREGATOR_SRC_PAD:
366  * @agg: a #GstAggregator
367  *
368  * Convenience macro to access the source pad of #GstAggregator
369  *
370  * Since: 1.6
371  */
372 #define GST_AGGREGATOR_SRC_PAD(agg) (((GstAggregator *)(agg))->srcpad)
373 
374 /*************************
375  * GstAggregator methods *
376  ************************/
377 
378 GST_BASE_API
379 GstFlowReturn  gst_aggregator_finish_buffer         (GstAggregator                *  aggregator,
380                                                      GstBuffer                    *  buffer);
381 
382 GST_BASE_API
383 GstFlowReturn  gst_aggregator_finish_buffer_list    (GstAggregator                *  aggregator,
384                                                      GstBufferList                *  bufferlist);
385 
386 GST_BASE_API
387 void           gst_aggregator_set_src_caps          (GstAggregator                *  self,
388                                                      GstCaps                      *  caps);
389 
390 GST_BASE_API
391 gboolean        gst_aggregator_negotiate            (GstAggregator                * self);
392 
393 GST_BASE_API
394 void           gst_aggregator_set_latency           (GstAggregator                *  self,
395                                                      GstClockTime                    min_latency,
396                                                      GstClockTime                    max_latency);
397 
398 GST_BASE_API
399 GType gst_aggregator_get_type(void);
400 
401 GST_BASE_API
402 GstClockTime  gst_aggregator_get_latency           (GstAggregator                 *  self);
403 
404 GST_BASE_API
405 GstBufferPool * gst_aggregator_get_buffer_pool     (GstAggregator                 * self);
406 
407 GST_BASE_API
408 void            gst_aggregator_get_allocator       (GstAggregator                 * self,
409                                                     GstAllocator                 ** allocator,
410                                                     GstAllocationParams           * params);
411 
412 GST_BASE_API
413 GstClockTime    gst_aggregator_simple_get_next_time (GstAggregator                * self);
414 
415 GST_BASE_API
416 void            gst_aggregator_update_segment       (GstAggregator                * self,
417                                                      const GstSegment             * segment);
418 
419 GST_BASE_API
420 GstSample     * gst_aggregator_peek_next_sample     (GstAggregator *self,
421                                                      GstAggregatorPad * pad);
422 
423 GST_BASE_API
424 void            gst_aggregator_selected_samples     (GstAggregator                * self,
425                                                      GstClockTime                   pts,
426                                                      GstClockTime                   dts,
427                                                      GstClockTime                   duration,
428                                                      GstStructure                 * info);
429 
430 GST_BASE_API
431 void            gst_aggregator_set_ignore_inactive_pads (GstAggregator * self,
432                                                          gboolean ignore);
433 
434 GST_BASE_API
435 gboolean        gst_aggregator_get_ignore_inactive_pads (GstAggregator * self);
436 
437 /**
438  * GstAggregatorStartTimeSelection:
439  * @GST_AGGREGATOR_START_TIME_SELECTION_ZERO: Start at running time 0.
440  * @GST_AGGREGATOR_START_TIME_SELECTION_FIRST: Start at the running time of
441  * the first buffer that is received.
442  * @GST_AGGREGATOR_START_TIME_SELECTION_SET: Start at the running time
443  * selected by the `start-time` property.
444  *
445  * Since: 1.18
446  */
447 typedef enum
448 {
449   GST_AGGREGATOR_START_TIME_SELECTION_ZERO,
450   GST_AGGREGATOR_START_TIME_SELECTION_FIRST,
451   GST_AGGREGATOR_START_TIME_SELECTION_SET
452 } GstAggregatorStartTimeSelection;
453 
454 GST_BASE_API
455 GType           gst_aggregator_start_time_selection_get_type (void);
456 
457 G_END_DECLS
458 
459 G_DEFINE_AUTOPTR_CLEANUP_FUNC(GstAggregator, gst_object_unref)
460 G_DEFINE_AUTOPTR_CLEANUP_FUNC(GstAggregatorPad, gst_object_unref)
461 
462 #endif /* __GST_AGGREGATOR_H__ */
463