gstevent.c 27.6 KB
Newer Older
1 2 3
/* GStreamer
 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
 *                    2000 Wim Taymans <wim.taymans@chello.be>
4
 *                    2005 Wim Taymans <wim@fluendo.com>
5
 *
6
 * gstevent.c: GstEvent subsystem
7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
23

24 25
/**
 * SECTION:gstevent
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
26 27
 * @short_description: Structure describing events that are passed up and down
 *                     a pipeline
28 29
 * @see_also: #GstPad, #GstElement
 *
30 31
 * The event class provides factory methods to construct and functions query
 * (parse) events.
32
 *
33 34
 * Events are usually created with gst_event_new_*() which takes event-type
 * specific parameters as arguments.
35 36
 * To send an event application will usually use gst_element_send_event() and
 * elements will use gst_pad_send_event() or gst_pad_push_event().
37 38 39 40
 * The event should be unreffed with gst_event_unref() if it has not been sent.
 *
 * Events that have been received can be parsed with their respective 
 * gst_event_parse_*() functions.
41
 *
Wim Taymans's avatar
Wim Taymans committed
42 43 44 45
 * Events are passed between elements in parallel to the data stream. Some events
 * are serialized with buffers, others are not. Some events only travel downstream,
 * others only upstream. Some events can travel both upstream and downstream. 
 * 
46 47 48
 * The events are used to signal special conditions in the datastream such as
 * EOS (end of stream) or the start of a new stream-segment.
 * Events are also used to flush the pipeline of any pending data.
Wim Taymans's avatar
Wim Taymans committed
49
 *
50 51 52 53
 * Most of the event API is used inside plugins. Applications usually only 
 * construct and use seek events. 
 * To do that gst_event_new_seek() is used to create a seek event. It takes
 * the needed parameters to specity seeking time and mode.
Wim Taymans's avatar
Wim Taymans committed
54 55 56 57 58 59 60 61 62 63
 * <example>
 * <title>performing a seek on a pipeline</title>
 *   <programlisting>
 *   GstEvent *event;
 *   gboolean result;
 *   ...
 *   // construct a seek event to play the media from second 2 to 5, flush
 *   // the pipeline to decrease latency.
 *   event = gst_event_new_seek (1.0, 
 *      GST_FORMAT_TIME, 
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
64 65 66
 *      GST_SEEK_FLAG_FLUSH,
 *      GST_SEEK_TYPE_SET, 2 * GST_SECOND,
 *      GST_SEEK_TYPE_SET, 5 * GST_SECOND);
Wim Taymans's avatar
Wim Taymans committed
67 68 69 70 71 72 73
 *   ...
 *   result = gst_element_send_event (pipeline, event);
 *   if (!result)
 *     g_warning ("seek failed");
 *   ...
 *   </programlisting>
 * </example>
Wim Taymans's avatar
Wim Taymans committed
74
 *
75
 * Last reviewed on 2006-01-24 (0.10.2)
76
 */
Wim Taymans's avatar
Wim Taymans committed
77

78

79
#include "gst_private.h"
80
#include <string.h>             /* memcpy */
81 82

#include "gstinfo.h"
83
#include "gstevent.h"
Wim Taymans's avatar
Wim Taymans committed
84
#include "gstenumtypes.h"
85
#include "gstutils.h"
Benjamin Otte's avatar
Benjamin Otte committed
86

87 88 89 90
static void gst_event_init (GTypeInstance * instance, gpointer g_class);
static void gst_event_class_init (gpointer g_class, gpointer class_data);
static void gst_event_finalize (GstEvent * event);
static GstEvent *_gst_event_copy (GstEvent * event);
91 92 93 94

void
_gst_event_initialize (void)
{
95 96 97
  gst_event_get_type ();
}

98 99 100 101 102 103 104 105 106 107 108 109 110 111
typedef struct
{
  gint type;
  gchar *name;
  GQuark quark;
} GstEventQuarks;

static GstEventQuarks event_quarks[] = {
  {GST_EVENT_UNKNOWN, "unknown", 0},
  {GST_EVENT_FLUSH_START, "flush-start", 0},
  {GST_EVENT_FLUSH_STOP, "flush-stop", 0},
  {GST_EVENT_EOS, "eos", 0},
  {GST_EVENT_NEWSEGMENT, "newsegment", 0},
  {GST_EVENT_TAG, "tag", 0},
112
  {GST_EVENT_BUFFERSIZE, "buffersize", 0},
113 114 115
  {GST_EVENT_QOS, "qos", 0},
  {GST_EVENT_SEEK, "seek", 0},
  {GST_EVENT_NAVIGATION, "navigation", 0},
116 117 118
  {GST_EVENT_CUSTOM_UPSTREAM, "custom-upstream", 0},
  {GST_EVENT_CUSTOM_DOWNSTREAM, "custom-downstream", 0},
  {GST_EVENT_CUSTOM_DOWNSTREAM_OOB, "custom-downstream-oob", 0},
119 120 121
  {GST_EVENT_CUSTOM_BOTH, "custom-both", 0},
  {GST_EVENT_CUSTOM_BOTH_OOB, "custom-both-oob", 0},

122 123 124
  {0, NULL, 0}
};

Stefan Kost's avatar
Stefan Kost committed
125 126 127 128 129 130
/**
 * gst_event_type_get_name:
 * @type: the event type
 *
 * Get a printable name for the given event type. Do not modify or free.
 *
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
131
 * Returns: a reference to the static name of the event.
Stefan Kost's avatar
Stefan Kost committed
132
 */
133 134 135 136 137 138 139 140 141 142 143 144
const gchar *
gst_event_type_get_name (GstEventType type)
{
  gint i;

  for (i = 0; event_quarks[i].name; i++) {
    if (type == event_quarks[i].type)
      return event_quarks[i].name;
  }
  return "unknown";
}

Stefan Kost's avatar
Stefan Kost committed
145 146 147 148 149 150 151 152
/**
 * gst_event_type_to_quark:
 * @type: the event type
 *
 * Get the unique quark for the given event type.
 *
 * Returns: the quark associated with the event type
 */
153 154 155 156 157 158 159 160 161 162 163 164
GQuark
gst_event_type_to_quark (GstEventType type)
{
  gint i;

  for (i = 0; event_quarks[i].name; i++) {
    if (type == event_quarks[i].type)
      return event_quarks[i].quark;
  }
  return 0;
}

165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182
/**
 * gst_event_type_get_flags:
 * @type: a #GstEventType
 *
 * Gets the #GstEventTypeFlags associated with @type.
 *
 * Returns: a #GstEventTypeFlags.
 */
GstEventTypeFlags
gst_event_type_get_flags (GstEventType type)
{
  GstEventTypeFlags ret;

  ret = type & ((1 << GST_EVENT_TYPE_SHIFT) - 1);

  return ret;
}

183 184 185 186
GType
gst_event_get_type (void)
{
  static GType _gst_event_type;
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
187
  int i;
188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204

  if (G_UNLIKELY (_gst_event_type == 0)) {
    static const GTypeInfo event_info = {
      sizeof (GstEventClass),
      NULL,
      NULL,
      gst_event_class_init,
      NULL,
      NULL,
      sizeof (GstEvent),
      0,
      gst_event_init,
      NULL
    };

    _gst_event_type = g_type_register_static (GST_TYPE_MINI_OBJECT,
        "GstEvent", &event_info, 0);
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
205 206 207 208

    for (i = 0; event_quarks[i].name; i++) {
      event_quarks[i].quark = g_quark_from_static_string (event_quarks[i].name);
    }
209
  }
210

211
  return _gst_event_type;
212 213
}

214 215
static void
gst_event_class_init (gpointer g_class, gpointer class_data)
Wim Taymans's avatar
Wim Taymans committed
216
{
217
  GstEventClass *event_class = GST_EVENT_CLASS (g_class);
Wim Taymans's avatar
Wim Taymans committed
218

219 220 221 222 223
  event_class->mini_object_class.copy =
      (GstMiniObjectCopyFunction) _gst_event_copy;
  event_class->mini_object_class.finalize =
      (GstMiniObjectFinalizeFunction) gst_event_finalize;
}
Wim Taymans's avatar
Wim Taymans committed
224

225 226 227 228
static void
gst_event_init (GTypeInstance * instance, gpointer g_class)
{
  GstEvent *event;
229

230
  event = GST_EVENT (instance);
Wim Taymans's avatar
Wim Taymans committed
231

232
  GST_EVENT_TIMESTAMP (event) = GST_CLOCK_TIME_NONE;
Wim Taymans's avatar
Wim Taymans committed
233 234
}

235
static void
236
gst_event_finalize (GstEvent * event)
237
{
238 239 240
  g_return_if_fail (event != NULL);
  g_return_if_fail (GST_IS_EVENT (event));

241
  GST_CAT_LOG (GST_CAT_EVENT, "freeing event %p type %s", event,
242
      GST_EVENT_TYPE_NAME (event));
Wim Taymans's avatar
Wim Taymans committed
243

244 245
  if (GST_EVENT_SRC (event)) {
    gst_object_unref (GST_EVENT_SRC (event));
246
    GST_EVENT_SRC (event) = NULL;
247
  }
Wim Taymans's avatar
Wim Taymans committed
248 249 250
  if (event->structure) {
    gst_structure_set_parent_refcount (event->structure, NULL);
    gst_structure_free (event->structure);
251
  }
252 253 254 255 256 257 258
}

static GstEvent *
_gst_event_copy (GstEvent * event)
{
  GstEvent *copy;

Wim Taymans's avatar
Wim Taymans committed
259
  copy = (GstEvent *) gst_mini_object_new (GST_TYPE_EVENT);
260

Wim Taymans's avatar
Wim Taymans committed
261 262
  GST_EVENT_TYPE (copy) = GST_EVENT_TYPE (event);
  GST_EVENT_TIMESTAMP (copy) = GST_EVENT_TIMESTAMP (event);
263

Wim Taymans's avatar
Wim Taymans committed
264 265 266 267 268 269 270
  if (GST_EVENT_SRC (event)) {
    GST_EVENT_SRC (copy) = gst_object_ref (GST_EVENT_SRC (event));
  }
  if (event->structure) {
    copy->structure = gst_structure_copy (event->structure);
    gst_structure_set_parent_refcount (copy->structure,
        &event->mini_object.refcount);
271 272
  }
  return copy;
273 274
}

Wim Taymans's avatar
Wim Taymans committed
275 276
static GstEvent *
gst_event_new (GstEventType type)
277
{
Wim Taymans's avatar
Wim Taymans committed
278
  GstEvent *event;
279

Wim Taymans's avatar
Wim Taymans committed
280
  event = (GstEvent *) gst_mini_object_new (GST_TYPE_EVENT);
281

282
  GST_CAT_DEBUG (GST_CAT_EVENT, "creating new event %p %s", event,
283
      gst_event_type_get_name (type));
284

Wim Taymans's avatar
Wim Taymans committed
285 286 287
  event->type = type;
  event->src = NULL;
  event->structure = NULL;
288

Wim Taymans's avatar
Wim Taymans committed
289
  return event;
290 291
}

292
/**
Wim Taymans's avatar
Wim Taymans committed
293
 * gst_event_new_custom:
294
 * @type: The type of the new event
Wim Taymans's avatar
Wim Taymans committed
295 296
 * @structure: The structure for the event. The event will take ownership of
 * the structure.
297
 *
Wim Taymans's avatar
Wim Taymans committed
298 299 300
 * Create a new custom-typed event. This can be used for anything not
 * handled by other event-specific functions to pass an event to another
 * element.
301
 *
Wim Taymans's avatar
Wim Taymans committed
302 303 304 305 306 307 308 309
 * Make sure to allocate an event type with the #GST_EVENT_MAKE_TYPE macro,
 * assigning a free number and filling in the correct direction and
 * serialization flags.
 *
 * New custom events can also be created by subclassing the event type if
 * needed.
 *
 * Returns: The new custom event.
310
 */
311
GstEvent *
Wim Taymans's avatar
Wim Taymans committed
312
gst_event_new_custom (GstEventType type, GstStructure * structure)
313 314 315
{
  GstEvent *event;

Wim Taymans's avatar
Wim Taymans committed
316 317 318 319 320
  event = gst_event_new (type);
  if (structure) {
    gst_structure_set_parent_refcount (structure, &event->mini_object.refcount);
    event->structure = structure;
  }
321
  return event;
322 323
}

324
/**
Wim Taymans's avatar
Wim Taymans committed
325 326
 * gst_event_get_structure:
 * @event: The #GstEvent.
327
 *
Wim Taymans's avatar
Wim Taymans committed
328
 * Access the structure of the event.
329
 *
Wim Taymans's avatar
Wim Taymans committed
330 331 332 333 334
 * Returns: The structure of the event. The structure is still
 * owned by the event, which means that you should not free it and
 * that the pointer becomes invalid when you free the event.
 *
 * MT safe.
335
 */
Wim Taymans's avatar
Wim Taymans committed
336 337
const GstStructure *
gst_event_get_structure (GstEvent * event)
338
{
Wim Taymans's avatar
Wim Taymans committed
339
  g_return_val_if_fail (GST_IS_EVENT (event), NULL);
340

Wim Taymans's avatar
Wim Taymans committed
341
  return event->structure;
342
}
343

Wim Taymans's avatar
Wim Taymans committed
344
/**
Wim Taymans's avatar
Wim Taymans committed
345 346 347 348 349 350 351
 * gst_event_new_flush_start:
 *
 * Allocate a new flush start event. The flush start event can be send
 * upstream and downstream and travels out-of-bounds with the dataflow.
 * It marks pads as being in a WRONG_STATE to process more data.
 *
 * Elements unlock and blocking functions and exit their streaming functions
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
352
 * as fast as possible.
Wim Taymans's avatar
Wim Taymans committed
353
 *
Wim Taymans's avatar
Wim Taymans committed
354 355
 * This event is typically generated after a seek to minimize the latency
 * after the seek.
Wim Taymans's avatar
Wim Taymans committed
356
 *
Wim Taymans's avatar
Wim Taymans committed
357
 * Returns: A new flush start event.
Wim Taymans's avatar
Wim Taymans committed
358
 */
359
GstEvent *
Wim Taymans's avatar
Wim Taymans committed
360
gst_event_new_flush_start (void)
361
{
Wim Taymans's avatar
Wim Taymans committed
362
  return gst_event_new (GST_EVENT_FLUSH_START);
363 364
}

365
/**
Wim Taymans's avatar
Wim Taymans committed
366 367 368 369 370 371
 * gst_event_new_flush_stop:
 *
 * Allocate a new flush stop event. The flush start event can be send
 * upstream and downstream and travels out-of-bounds with the dataflow.
 * It is typically send after sending a FLUSH_START event to make the
 * pads accept data again.
372
 *
Wim Taymans's avatar
Wim Taymans committed
373 374
 * Elements can process this event synchronized with the dataflow since
 * the preceeding FLUSH_START event stopped the dataflow.
375
 *
Wim Taymans's avatar
Wim Taymans committed
376 377 378 379
 * This event is typically generated to complete a seek and to resume
 * dataflow.
 *
 * Returns: A new flush stop event.
380
 */
381
GstEvent *
Wim Taymans's avatar
Wim Taymans committed
382
gst_event_new_flush_stop (void)
383
{
Wim Taymans's avatar
Wim Taymans committed
384
  return gst_event_new (GST_EVENT_FLUSH_STOP);
385 386
}

Wim Taymans's avatar
Wim Taymans committed
387
/**
Wim Taymans's avatar
Wim Taymans committed
388
 * gst_event_new_eos:
Wim Taymans's avatar
Wim Taymans committed
389
 *
Wim Taymans's avatar
Wim Taymans committed
390 391 392 393
 * Create a new EOS event. The eos event can only travel downstream
 * synchronized with the buffer flow. Elements that receive the EOS
 * event on a pad can return UNEXPECTED as a GstFlowReturn when data
 * after the EOS event arrives.
Wim Taymans's avatar
Wim Taymans committed
394
 *
Jan Schmidt's avatar
Jan Schmidt committed
395 396 397
 * The EOS event will travel down to the sink elements in the pipeline
 * which will then post the GST_MESSAGE_EOS on the bus after they have
 * finished playing any buffered data.
Wim Taymans's avatar
Wim Taymans committed
398 399 400 401 402
 *
 * When all sinks have posted an EOS message, the EOS message is
 * forwarded to the application.
 *
 * Returns: The new EOS event.
Wim Taymans's avatar
Wim Taymans committed
403
 */
Wim Taymans's avatar
Wim Taymans committed
404 405
GstEvent *
gst_event_new_eos (void)
406
{
Wim Taymans's avatar
Wim Taymans committed
407
  return gst_event_new (GST_EVENT_EOS);
408 409
}

410
/**
411
 * gst_event_new_new_segment:
412
 * @update: is this segment an update to a previous one
Wim Taymans's avatar
Wim Taymans committed
413 414
 * @rate: a new rate for playback
 * @format: The format of the segment values
415 416 417
 * @start: the start value of the segment
 * @stop: the stop value of the segment
 * @position: stream position
Wim Taymans's avatar
Wim Taymans committed
418
 *
419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467
 * Allocate a new newsegment event with the given format/values tripplets
 *
 * This method calls gst_event_new_new_segment_full() passing a default
 * value of 1.0 for applied_rate
 */
GstEvent *
gst_event_new_new_segment (gboolean update, gdouble rate, GstFormat format,
    gint64 start, gint64 stop, gint64 position)
{
  return gst_event_new_new_segment_full (update, rate, 1.0, format, start,
      stop, position);
}

/**
 * gst_event_parse_new_segment:
 * @event: The event to query
 * @update: A pointer to the update flag of the segment
 * @rate: A pointer to the rate of the segment
 * @format: A pointer to the format of the newsegment values
 * @start: A pointer to store the start value in
 * @stop: A pointer to store the stop value in
 * @position: A pointer to store the stream time in
 *
 * Get the update flag, rate, format, start, stop and position in the 
 * newsegment event. In general, gst_event_parse_new_segment_full() should
 * be used instead of this, to also retrieve the applied_rate value of the
 * segment. See gst_event_new_new_segment_full() for a full description 
 * of the newsegment event.
 */
void
gst_event_parse_new_segment (GstEvent * event, gboolean * update,
    gdouble * rate, GstFormat * format, gint64 * start,
    gint64 * stop, gint64 * position)
{
  gst_event_parse_new_segment_full (event, update, rate, NULL, format, start,
      stop, position);
}

/**
 * gst_event_new_new_segment_full:
 * @update: Whether this segment is an update to a previous one
 * @rate: A new rate for playback
 * @applied_rate: The rate factor which has already been applied
 * @format: The format of the segment values
 * @start: The start value of the segment
 * @stop: The stop value of the segment
 * @position: stream position
 *
 * Allocate a new newsegment event with the given format/values triplets.
Wim Taymans's avatar
Wim Taymans committed
468 469
 *
 * The newsegment event marks the range of buffers to be processed. All
470
 * data not within the segment range is not to be processed. This can be
471
 * used intelligently by plugins to apply more efficient methods of skipping
472
 * unneeded packets.
473
 *
474 475 476 477 478
 * The position value of the segment is used in conjunction with the start
 * value to convert the buffer timestamps into the stream time. This is 
 * usually done in sinks to report the current stream_time. 
 * @position represents the stream_time of a buffer carrying a timestamp of 
 * @start. @position cannot be -1.
479
 *
480
 * @start cannot be -1, @stop can be -1. If there
481 482 483 484 485 486 487 488 489 490
 * is a valid @stop given, it must be greater or equal the @start, including 
 * when the indicated playback @rate is < 0
 *
 * The @applied_rate value provides information about any rate adjustment that
 * has already been made to the timestamps and content on the buffers of the 
 * stream. (@rate * @applied_rate) should always equal the rate that has been 
 * requested for playback. For example, if an element has an input segment 
 * with intended playback @rate of 2.0 and applied_rate of 1.0, it can adjust 
 * incoming timestamps and buffer content by half and output a newsegment event 
 * with @rate of 1.0 and @applied_rate of 2.0
491
 *
Wim Taymans's avatar
Wim Taymans committed
492 493
 * After a newsegment event, the buffer stream time is calculated with:
 *
494
 *   position + (TIMESTAMP(buf) - start) * ABS (rate * applied_rate)
Wim Taymans's avatar
Wim Taymans committed
495 496
 *
 * Returns: A new newsegment event.
497 498
 *
 * Since: 0.10.6
499
 */
500
GstEvent *
501 502 503
gst_event_new_new_segment_full (gboolean update, gdouble rate,
    gdouble applied_rate, GstFormat format, gint64 start, gint64 stop,
    gint64 position)
504
{
505
  g_return_val_if_fail (rate != 0.0, NULL);
506
  g_return_val_if_fail (applied_rate != 0.0, NULL);
507

508 509
  if (format == GST_FORMAT_TIME) {
    GST_CAT_INFO (GST_CAT_EVENT,
510
        "creating newsegment update %d, rate %lf, format GST_FORMAT_TIME, "
511
        "start %" GST_TIME_FORMAT ", stop %" GST_TIME_FORMAT
512 513 514
        ", position %" GST_TIME_FORMAT,
        update, rate, GST_TIME_ARGS (start),
        GST_TIME_ARGS (stop), GST_TIME_ARGS (position));
515 516
  } else {
    GST_CAT_INFO (GST_CAT_EVENT,
517
        "creating newsegment update %d, rate %lf, format %d, "
518 519
        "start %" G_GINT64_FORMAT ", stop %" G_GINT64_FORMAT ", position %"
        G_GINT64_FORMAT, update, rate, format, start, stop, position);
520
  }
521

522 523 524 525
  g_return_val_if_fail (position != -1, NULL);
  g_return_val_if_fail (start != -1, NULL);
  if (stop != -1)
    g_return_val_if_fail (start <= stop, NULL);
526

Wim Taymans's avatar
Wim Taymans committed
527
  return gst_event_new_custom (GST_EVENT_NEWSEGMENT,
528 529 530
      gst_structure_new ("GstEventNewsegment",
          "update", G_TYPE_BOOLEAN, update,
          "rate", G_TYPE_DOUBLE, rate,
531
          "applied_rate", G_TYPE_DOUBLE, applied_rate,
Wim Taymans's avatar
Wim Taymans committed
532
          "format", GST_TYPE_FORMAT, format,
533 534 535
          "start", G_TYPE_INT64, start,
          "stop", G_TYPE_INT64, stop,
          "position", G_TYPE_INT64, position, NULL));
Wim Taymans's avatar
Wim Taymans committed
536
}
537

Wim Taymans's avatar
Wim Taymans committed
538
/**
539
 * gst_event_parse_new_segment_full:
Wim Taymans's avatar
Wim Taymans committed
540
 * @event: The event to query
541
 * @update: A pointer to the update flag of the segment
Wim Taymans's avatar
Wim Taymans committed
542
 * @rate: A pointer to the rate of the segment
543
 * @applied_rate: A pointer to the applied_rate of the segment
Wim Taymans's avatar
Wim Taymans committed
544
 * @format: A pointer to the format of the newsegment values
545 546 547
 * @start: A pointer to store the start value in
 * @stop: A pointer to store the stop value in
 * @position: A pointer to store the stream time in
Wim Taymans's avatar
Wim Taymans committed
548
 *
549 550 551 552 553
 * Get the update, rate, applied_rate, format, start, stop and 
 * position in the newsegment event. See gst_event_new_new_segment_full() 
 * for a full description of the newsegment event.
 *
 * Since: 0.10.6
Wim Taymans's avatar
Wim Taymans committed
554 555
 */
void
556 557 558
gst_event_parse_new_segment_full (GstEvent * event, gboolean * update,
    gdouble * rate, gdouble * applied_rate, GstFormat * format,
    gint64 * start, gint64 * stop, gint64 * position)
Wim Taymans's avatar
Wim Taymans committed
559 560
{
  const GstStructure *structure;
561

Wim Taymans's avatar
Wim Taymans committed
562 563 564 565
  g_return_if_fail (GST_IS_EVENT (event));
  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_NEWSEGMENT);

  structure = gst_event_get_structure (event);
566
  if (G_LIKELY (update))
567 568
    *update =
        g_value_get_boolean (gst_structure_get_value (structure, "update"));
569
  if (G_LIKELY (rate))
Wim Taymans's avatar
Wim Taymans committed
570
    *rate = g_value_get_double (gst_structure_get_value (structure, "rate"));
571 572 573 574 575
  if (G_LIKELY (applied_rate))
    *applied_rate =
        g_value_get_double (gst_structure_get_value (structure,
            "applied_rate"));
  if (G_LIKELY (format))
Wim Taymans's avatar
Wim Taymans committed
576
    *format = g_value_get_enum (gst_structure_get_value (structure, "format"));
577
  if (G_LIKELY (start))
578
    *start = g_value_get_int64 (gst_structure_get_value (structure, "start"));
579
  if (G_LIKELY (stop))
580
    *stop = g_value_get_int64 (gst_structure_get_value (structure, "stop"));
581
  if (G_LIKELY (position))
582 583
    *position =
        g_value_get_int64 (gst_structure_get_value (structure, "position"));
Wim Taymans's avatar
Wim Taymans committed
584
}
585

586 587 588 589 590
/**
 * gst_event_new_tag:
 * @taglist: metadata list
 *
 * Generates a metadata tag event from the given @taglist.
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
591
 *
592 593
 * Returns: a new #GstEvent
 */
Wim Taymans's avatar
Wim Taymans committed
594 595 596 597 598
GstEvent *
gst_event_new_tag (GstTagList * taglist)
{
  g_return_val_if_fail (taglist != NULL, NULL);
  return gst_event_new_custom (GST_EVENT_TAG, (GstStructure *) taglist);
599 600
}

601 602 603 604 605 606 607
/**
 * gst_event_parse_tag:
 * @event: a tag event
 * @taglist: pointer to metadata list
 *
 * Parses a tag @event and stores the results in the given @taglist location.
 */
Wim Taymans's avatar
Wim Taymans committed
608 609 610 611 612 613 614 615 616
void
gst_event_parse_tag (GstEvent * event, GstTagList ** taglist)
{
  g_return_if_fail (GST_IS_EVENT (event));
  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_TAG);
  if (taglist)
    *taglist = (GstTagList *) event->structure;
}

617 618
/* buffersize event */
/**
619
 * gst_event_new_buffer_size:
Stefan Kost's avatar
Stefan Kost committed
620 621 622 623
 * @format: buffer format
 * @minsize: minimum buffer size
 * @maxsize: maximum buffer size
 * @async: thread behavior
624 625 626 627 628 629 630 631 632
 *
 * Create a new buffersize event. The event is sent downstream and notifies
 * elements that they should provide a buffer of the specified dimensions.
 *
 * When the async flag is set, a thread boundary is prefered.
 *
 * Returns: a new #GstEvent
 */
GstEvent *
633
gst_event_new_buffer_size (GstFormat format, gint64 minsize,
634 635 636 637 638 639 640 641 642 643 644 645 646 647
    gint64 maxsize, gboolean async)
{
  GST_CAT_INFO (GST_CAT_EVENT,
      "creating buffersize format %d, minsize %" G_GINT64_FORMAT
      ", maxsize %" G_GINT64_FORMAT ", async %d", format,
      minsize, maxsize, async);
  return gst_event_new_custom (GST_EVENT_BUFFERSIZE,
      gst_structure_new ("GstEventBufferSize",
          "format", GST_TYPE_FORMAT, format,
          "minsize", G_TYPE_INT64, minsize,
          "maxsize", G_TYPE_INT64, maxsize,
          "async", G_TYPE_BOOLEAN, async, NULL));
}

Stefan Kost's avatar
Stefan Kost committed
648
/**
649
 * gst_event_parse_buffer_size:
Stefan Kost's avatar
Stefan Kost committed
650 651 652 653 654 655 656 657
 * @event: The event to query
 * @format: A pointer to store the format in
 * @minsize: A pointer to store the minsize in
 * @maxsize: A pointer to store the maxsize in
 * @async: A pointer to store the async-flag in
 *
 * Get the format, minsize, maxsize and async-flag in the buffersize event.
 */
658
void
659
gst_event_parse_buffer_size (GstEvent * event, GstFormat * format,
660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678
    gint64 * minsize, gint64 * maxsize, gboolean * async)
{
  const GstStructure *structure;

  g_return_if_fail (GST_IS_EVENT (event));
  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_BUFFERSIZE);
  structure = gst_event_get_structure (event);
  if (format)
    *format = g_value_get_enum (gst_structure_get_value (structure, "format"));
  if (minsize)
    *minsize =
        g_value_get_int64 (gst_structure_get_value (structure, "minsize"));
  if (maxsize)
    *maxsize =
        g_value_get_int64 (gst_structure_get_value (structure, "maxsize"));
  if (async)
    *async = g_value_get_boolean (gst_structure_get_value (structure, "async"));
}

679
/**
Wim Taymans's avatar
Wim Taymans committed
680 681 682 683 684 685 686 687
 * gst_event_new_qos:
 * @proportion: the proportion of the qos message
 * @diff: The time difference of the last Clock sync
 * @timestamp: The timestamp of the buffer
 *
 * Allocate a new qos event with the given values.
 * The QOS event is generated in an element that wants an upstream
 * element to either reduce or increase its rate because of
688
 * high/low CPU load or other resource usage such as network performance.
Wim Taymans's avatar
Wim Taymans committed
689
 *
690
 * @proportion is the requested adjustment in datarate, 1.0 is the normal
Wim Taymans's avatar
Wim Taymans committed
691 692
 * datarate, 0.75 means increase datarate by 75%, 1.5 is 150%. Negative
 * values request a slow down, so -0.75 means a decrease by 75%.
693
 *
694
 * @diff is the difference against the clock in stream time of the last
Wim Taymans's avatar
Wim Taymans committed
695
 * buffer that caused the element to generate the QOS event.
696
 *
697 698 699 700 701 702 703 704 705 706 707 708 709
 * @timestamp is the timestamp of the last buffer that cause the element
 * to generate the QOS event. 
 *
 * The upstream element can use the @diff and @timestamp values to decide
 * whether to process more buffers. All buffers with timestamp <=
 * @timestamp + @diff will certainly arrive late in the sink as well. 
 *
 * The @proportion value is generally computed based on more long
 * term statistics about the stream quality and can be used in various ways
 * such as lowering or increasing processing quality.
 *
 * The application can use general event probes to intercept the QoS
 * event and implement custom application specific QoS handling.
Wim Taymans's avatar
Wim Taymans committed
710 711
 *
 * Returns: A new QOS event.
712
 */
713
GstEvent *
Wim Taymans's avatar
Wim Taymans committed
714 715
gst_event_new_qos (gdouble proportion, GstClockTimeDiff diff,
    GstClockTime timestamp)
716
{
717
  GST_CAT_INFO (GST_CAT_EVENT,
718
      "creating qos proportion %lf, diff %" G_GINT64_FORMAT
719
      ", timestamp %" GST_TIME_FORMAT, proportion,
720
      diff, GST_TIME_ARGS (timestamp));
721

Wim Taymans's avatar
Wim Taymans committed
722 723 724 725 726 727
  return gst_event_new_custom (GST_EVENT_QOS,
      gst_structure_new ("GstEventQOS",
          "proportion", G_TYPE_DOUBLE, proportion,
          "diff", G_TYPE_INT64, diff,
          "timestamp", G_TYPE_UINT64, timestamp, NULL));
}
728

Wim Taymans's avatar
Wim Taymans committed
729 730 731 732 733 734 735 736 737 738 739 740 741 742
/**
 * gst_event_parse_qos:
 * @event: The event to query
 * @proportion: A pointer to store the proportion in
 * @diff: A pointer to store the diff in
 * @timestamp: A pointer to store the timestamp in
 *
 * Get the proportion, diff and timestamp in the qos event.
 */
void
gst_event_parse_qos (GstEvent * event, gdouble * proportion,
    GstClockTimeDiff * diff, GstClockTime * timestamp)
{
  const GstStructure *structure;
743

Wim Taymans's avatar
Wim Taymans committed
744 745 746 747 748 749 750 751 752 753 754
  g_return_if_fail (GST_IS_EVENT (event));
  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_QOS);
  structure = gst_event_get_structure (event);
  if (proportion)
    *proportion =
        g_value_get_double (gst_structure_get_value (structure, "proportion"));
  if (diff)
    *diff = g_value_get_int64 (gst_structure_get_value (structure, "diff"));
  if (timestamp)
    *timestamp =
        g_value_get_uint64 (gst_structure_get_value (structure, "timestamp"));
755
}
756 757

/**
Wim Taymans's avatar
Wim Taymans committed
758 759 760
 * gst_event_new_seek:
 * @rate: The new playback rate
 * @format: The format of the seek values
Thomas Vander Stichele's avatar
Thomas Vander Stichele committed
761
 * @flags: The optional seek flags
Wim Taymans's avatar
Wim Taymans committed
762 763 764 765 766 767 768
 * @cur_type: The type and flags for the new current position
 * @cur: The value of the new current position
 * @stop_type: The type and flags for the new stop position
 * @stop: The value of the new stop position
 *
 * Allocate a new seek event with the given parameters.
 *
769
 * The seek event configures playback of the pipeline from
Wim Taymans's avatar
Wim Taymans committed
770
 * @cur to @stop at the speed given in @rate, also called a segment.
Wim Taymans's avatar
Wim Taymans committed
771
 * The @cur and @stop values are expressed in format @format.
772
 *
Wim Taymans's avatar
Wim Taymans committed
773 774 775
 * A @rate of 1.0 means normal playback rate, 2.0 means double speed.
 * Negatives values means backwards playback. A value of 0.0 for the
 * rate is not allowed.
776
 *
Wim Taymans's avatar
Wim Taymans committed
777
 * @cur_type and @stop_type specify how to adjust the current and stop
Wim Taymans's avatar
Wim Taymans committed
778 779 780
 * time, relative or absolute. A type of #GST_SEEK_TYPE_NONE means that
 * the position should not be updated. The currently configured playback
 * segment can be queried with #GST_QUERY_SEGMENT.
Wim Taymans's avatar
Wim Taymans committed
781
 *
782 783 784 785 786 787
 * Note that updating the @cur position will actually move the current
 * playback pointer to that new position. It is not possible to seek 
 * relative to the current playing position, to do this, pause the pipeline,
 * get the current position and perform a GST_SEEK_TYPE_SET to the desired
 * position.
 *
Wim Taymans's avatar
Wim Taymans committed
788
 * Returns: A new seek event.
789 790
 */
GstEvent *
Wim Taymans's avatar
Wim Taymans committed
791 792
gst_event_new_seek (gdouble rate, GstFormat format, GstSeekFlags flags,
    GstSeekType cur_type, gint64 cur, GstSeekType stop_type, gint64 stop)
793
{
794 795 796 797 798 799 800 801 802 803 804 805 806 807 808
  if (format == GST_FORMAT_TIME) {
    GST_CAT_INFO (GST_CAT_EVENT,
        "creating seek rate %lf, format TIME, flags %d, "
        "cur_type %d, cur %" GST_TIME_FORMAT ", "
        "stop_type %d, stop %" GST_TIME_FORMAT,
        rate, flags, cur_type, GST_TIME_ARGS (cur),
        stop_type, GST_TIME_ARGS (stop));
  } else {
    GST_CAT_INFO (GST_CAT_EVENT,
        "creating seek rate %lf, format %d, flags %d, "
        "cur_type %d, cur %" G_GINT64_FORMAT ", "
        "stop_type %d, stop %" G_GINT64_FORMAT,
        rate, format, flags, cur_type, cur, stop_type, stop);
  }

Wim Taymans's avatar
Wim Taymans committed
809 810 811 812 813 814 815 816 817
  return gst_event_new_custom (GST_EVENT_SEEK,
      gst_structure_new ("GstEventSeek", "rate", G_TYPE_DOUBLE, rate,
          "format", GST_TYPE_FORMAT, format,
          "flags", GST_TYPE_SEEK_FLAGS, flags,
          "cur_type", GST_TYPE_SEEK_TYPE, cur_type,
          "cur", G_TYPE_INT64, cur,
          "stop_type", GST_TYPE_SEEK_TYPE, stop_type,
          "stop", G_TYPE_INT64, stop, NULL));
}
818

819 820 821 822 823 824 825 826 827 828 829 830 831
/**
 * gst_event_parse_seek:
 * @event: a seek event
 * @rate: result location for the rate
 * @format: result location for the stream format
 * @flags:  result location for the #GstSeekFlags
 * @cur_type: result location for the #GstSeekType of the current position
 * @cur: result location for the current postion expressed in @format
 * @stop_type:  result location for the #GstSeekType of the stop position
 * @stop: result location for the stop postion expressed in @format
 *
 * Parses a seek @event and stores the results in the given result locations.
 */
Wim Taymans's avatar
Wim Taymans committed
832
void
833 834 835
gst_event_parse_seek (GstEvent * event, gdouble * rate,
    GstFormat * format, GstSeekFlags * flags, GstSeekType * cur_type,
    gint64 * cur, GstSeekType * stop_type, gint64 * stop)
Wim Taymans's avatar
Wim Taymans committed
836 837
{
  const GstStructure *structure;
838

Wim Taymans's avatar
Wim Taymans committed
839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859
  g_return_if_fail (GST_IS_EVENT (event));
  g_return_if_fail (GST_EVENT_TYPE (event) == GST_EVENT_SEEK);
  structure = gst_event_get_structure (event);
  if (rate)
    *rate = g_value_get_double (gst_structure_get_value (structure, "rate"));
  if (format)
    *format = g_value_get_enum (gst_structure_get_value (structure, "format"));
  if (flags)
    *flags = g_value_get_flags (gst_structure_get_value (structure, "flags"));
  if (cur_type)
    *cur_type =
        g_value_get_enum (gst_structure_get_value (structure, "cur_type"));
  if (cur)
    *cur = g_value_get_int64 (gst_structure_get_value (structure, "cur"));
  if (stop_type)
    *stop_type =
        g_value_get_enum (gst_structure_get_value (structure, "stop_type"));
  if (stop)
    *stop = g_value_get_int64 (gst_structure_get_value (structure, "stop"));
}

860 861 862 863 864 865 866 867
/**
 * gst_event_new_navigation:
 * @structure: description of the event
 *
 * Create a new navigation event from the given description.
 *
 * Returns: a new #GstEvent
 */
Wim Taymans's avatar
Wim Taymans committed
868 869 870 871 872
GstEvent *
gst_event_new_navigation (GstStructure * structure)
{
  g_return_val_if_fail (structure != NULL, NULL);
  return gst_event_new_custom (GST_EVENT_NAVIGATION, structure);
873
}