gstreamer/gst/gstpipeline.c
Wim Taymans 9d8037eed8 gst/gstpipeline.c: Fix small typo in docs.
Original commit message from CVS:
* gst/gstpipeline.c:
Fix small typo in docs.
2005-12-05 10:18:27 +00:00

636 lines
18 KiB
C

/* GStreamer
* Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
* 2004,2005 Wim Taymans <wim@fluendo.com>
*
* gstpipeline.c: Overall pipeline management element
*
* 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.
*/
/**
* SECTION:gstpipeline
* @short_description: Top-level bin with clocking and bus management
functionality.
* @see_also: #GstBin
*
* In almost all cases, you'll want to use a GstPipeline when creating a filter
* graph. The GstPipeline will manage the selection and distribution of a
* global
* clock as well as provide a GstBus to the application.
*
* The pipeline will also use the selected clock to calculate the stream time
* of the pipeline.
*
* When sending a seek event to a GstPipeline, it will make sure that the
* pipeline is properly PAUSED and resumed as well as update the new stream
* time after the seek.
*
* gst_pipeline_new() is used to create a pipeline. when you are done with
* the pipeline, use gst_object_unref() to free its resources including all
* added #GstElement objects (if not otherwise referenced).
*/
#include "gst_private.h"
#include "gsterror.h"
#include "gst-i18n-lib.h"
#include "gstpipeline.h"
#include "gstinfo.h"
#include "gstsystemclock.h"
static GstElementDetails gst_pipeline_details =
GST_ELEMENT_DETAILS ("Pipeline object",
"Generic/Bin",
"Complete pipeline object",
"Erik Walthinsen <omega@cse.ogi.edu>, Wim Taymans <wim@fluendo.com>");
/* Pipeline signals and args */
enum
{
/* FILL ME */
LAST_SIGNAL
};
#define DEFAULT_DELAY 0
enum
{
PROP_0,
PROP_DELAY,
/* FILL ME */
};
static void gst_pipeline_base_init (gpointer g_class);
static void gst_pipeline_class_init (gpointer g_class, gpointer class_data);
static void gst_pipeline_init (GTypeInstance * instance, gpointer g_class);
static void gst_pipeline_dispose (GObject * object);
static void gst_pipeline_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec);
static void gst_pipeline_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec);
static gboolean gst_pipeline_send_event (GstElement * element,
GstEvent * event);
static GstClock *gst_pipeline_provide_clock_func (GstElement * element);
static GstStateChangeReturn gst_pipeline_change_state (GstElement * element,
GstStateChange transition);
static GstBinClass *parent_class = NULL;
/* static guint gst_pipeline_signals[LAST_SIGNAL] = { 0 }; */
GType
gst_pipeline_get_type (void)
{
static GType pipeline_type = 0;
if (!pipeline_type) {
static const GTypeInfo pipeline_info = {
sizeof (GstPipelineClass),
gst_pipeline_base_init,
NULL,
(GClassInitFunc) gst_pipeline_class_init,
NULL,
NULL,
sizeof (GstPipeline),
0,
gst_pipeline_init,
NULL
};
pipeline_type =
g_type_register_static (GST_TYPE_BIN, "GstPipeline", &pipeline_info, 0);
}
return pipeline_type;
}
static void
gst_pipeline_base_init (gpointer g_class)
{
GstElementClass *gstelement_class = GST_ELEMENT_CLASS (g_class);
gst_element_class_set_details (gstelement_class, &gst_pipeline_details);
}
static void
gst_pipeline_class_init (gpointer g_class, gpointer class_data)
{
GObjectClass *gobject_class = G_OBJECT_CLASS (g_class);
GstElementClass *gstelement_class = GST_ELEMENT_CLASS (g_class);
GstPipelineClass *klass = GST_PIPELINE_CLASS (g_class);
parent_class = g_type_class_peek_parent (klass);
gobject_class->set_property = GST_DEBUG_FUNCPTR (gst_pipeline_set_property);
gobject_class->get_property = GST_DEBUG_FUNCPTR (gst_pipeline_get_property);
g_object_class_install_property (G_OBJECT_CLASS (klass), PROP_DELAY,
g_param_spec_uint64 ("delay", "Delay",
"Expected delay needed for elements "
"to spin up to PLAYING in nanoseconds", 0, G_MAXUINT64, DEFAULT_DELAY,
G_PARAM_READWRITE));
gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_pipeline_dispose);
gstelement_class->send_event = GST_DEBUG_FUNCPTR (gst_pipeline_send_event);
gstelement_class->change_state =
GST_DEBUG_FUNCPTR (gst_pipeline_change_state);
gstelement_class->provide_clock =
GST_DEBUG_FUNCPTR (gst_pipeline_provide_clock_func);
}
static void
gst_pipeline_init (GTypeInstance * instance, gpointer g_class)
{
GstPipeline *pipeline = GST_PIPELINE (instance);
GstBus *bus;
pipeline->delay = DEFAULT_DELAY;
bus = g_object_new (gst_bus_get_type (), NULL);
gst_element_set_bus (GST_ELEMENT_CAST (pipeline), bus);
gst_object_unref (bus);
}
static void
gst_pipeline_dispose (GObject * object)
{
GstPipeline *pipeline = GST_PIPELINE (object);
GST_CAT_DEBUG_OBJECT (GST_CAT_REFCOUNTING, pipeline, "dispose");
gst_object_replace ((GstObject **) & pipeline->fixed_clock, NULL);
G_OBJECT_CLASS (parent_class)->dispose (object);
}
static void
gst_pipeline_set_property (GObject * object, guint prop_id,
const GValue * value, GParamSpec * pspec)
{
GstPipeline *pipeline = GST_PIPELINE (object);
GST_OBJECT_LOCK (pipeline);
switch (prop_id) {
case PROP_DELAY:
pipeline->delay = g_value_get_uint64 (value);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
GST_OBJECT_UNLOCK (pipeline);
}
static void
gst_pipeline_get_property (GObject * object, guint prop_id,
GValue * value, GParamSpec * pspec)
{
GstPipeline *pipeline = GST_PIPELINE (object);
GST_OBJECT_LOCK (pipeline);
switch (prop_id) {
case PROP_DELAY:
g_value_set_uint64 (value, pipeline->delay);
break;
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
break;
}
GST_OBJECT_UNLOCK (pipeline);
}
static gboolean
do_pipeline_seek (GstElement * element, GstEvent * event)
{
gdouble rate;
GstSeekFlags flags;
gboolean flush;
gboolean was_playing = FALSE;
gboolean res;
gst_event_parse_seek (event, &rate, NULL, &flags, NULL, NULL, NULL, NULL);
flush = flags & GST_SEEK_FLAG_FLUSH;
if (flush) {
GstState state;
/* need to call _get_state() since a bin state is only updated
* with this call. */
gst_element_get_state (element, &state, NULL, 0);
was_playing = state == GST_STATE_PLAYING;
if (was_playing) {
gst_element_set_state (element, GST_STATE_PAUSED);
}
}
res = GST_ELEMENT_CLASS (parent_class)->send_event (element, event);
if (flush && res) {
gboolean need_reset;
GST_OBJECT_LOCK (element);
need_reset = GST_PIPELINE (element)->stream_time != GST_CLOCK_TIME_NONE;
GST_OBJECT_UNLOCK (element);
/* need to reset the stream time to 0 after a flushing seek, unless the user
explicitly disabled this behavior by setting stream time to NONE */
if (need_reset)
gst_pipeline_set_new_stream_time (GST_PIPELINE (element), 0);
if (was_playing)
/* and continue playing */
gst_element_set_state (element, GST_STATE_PLAYING);
}
return res;
}
/* sending a seek event on the pipeline pauses the pipeline if it
* was playing.
*/
static gboolean
gst_pipeline_send_event (GstElement * element, GstEvent * event)
{
gboolean res;
GstEventType event_type = GST_EVENT_TYPE (event);
switch (event_type) {
case GST_EVENT_SEEK:
res = do_pipeline_seek (element, event);
break;
default:
res = GST_ELEMENT_CLASS (parent_class)->send_event (element, event);
break;
}
return res;
}
/**
* gst_pipeline_new:
* @name: name of new pipeline
*
* Create a new pipeline with the given name.
*
* Returns: newly created GstPipeline
*
* MT safe.
*/
GstElement *
gst_pipeline_new (const gchar * name)
{
return gst_element_factory_make ("pipeline", name);
}
/* MT safe */
static GstStateChangeReturn
gst_pipeline_change_state (GstElement * element, GstStateChange transition)
{
GstStateChangeReturn result = GST_STATE_CHANGE_SUCCESS;
GstPipeline *pipeline = GST_PIPELINE (element);
GstClock *clock;
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
GST_OBJECT_LOCK (element);
if (element->bus)
gst_bus_set_flushing (element->bus, FALSE);
GST_OBJECT_UNLOCK (element);
break;
case GST_STATE_CHANGE_READY_TO_PAUSED:
break;
case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
{
GstClockTime new_base_time;
/* when going to playing, select a clock */
clock = gst_element_provide_clock (element);
if (clock) {
GstClockTime start_time, stream_time, delay;
gboolean new_clock;
start_time = gst_clock_get_time (clock);
GST_OBJECT_LOCK (element);
new_clock = element->clock != clock;
stream_time = pipeline->stream_time;
delay = pipeline->delay;
GST_OBJECT_UNLOCK (element);
if (new_clock) {
/* now distribute the clock (which could be NULL I guess) */
if (!gst_element_set_clock (element, clock))
goto invalid_clock;
/* if we selected a new clock, let the app know about it */
gst_element_post_message (element,
gst_message_new_new_clock (GST_OBJECT_CAST (element), clock));
}
if (stream_time != GST_CLOCK_TIME_NONE)
new_base_time = start_time - stream_time + delay;
else
new_base_time = GST_CLOCK_TIME_NONE;
gst_object_unref (clock);
} else {
GST_DEBUG ("no clock, using base time of 0");
new_base_time = 0;
}
if (new_base_time != GST_CLOCK_TIME_NONE)
gst_element_set_base_time (element, new_base_time);
else
GST_DEBUG_OBJECT (pipeline,
"NOT adjusting base time because stream time is NONE");
}
break;
case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
case GST_STATE_CHANGE_PAUSED_TO_READY:
case GST_STATE_CHANGE_READY_TO_NULL:
break;
}
result = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
break;
case GST_STATE_CHANGE_READY_TO_PAUSED:
{
gboolean need_reset;
GST_OBJECT_LOCK (element);
need_reset = pipeline->stream_time != GST_CLOCK_TIME_NONE;
GST_OBJECT_UNLOCK (element);
if (need_reset)
gst_pipeline_set_new_stream_time (pipeline, 0);
}
break;
case GST_STATE_CHANGE_PAUSED_TO_PLAYING:
break;
case GST_STATE_CHANGE_PLAYING_TO_PAUSED:
GST_OBJECT_LOCK (element);
if ((clock = element->clock)) {
GstClockTime now;
gst_object_ref (clock);
GST_OBJECT_UNLOCK (element);
/* calculate the time when we stopped */
now = gst_clock_get_time (clock);
gst_object_unref (clock);
GST_OBJECT_LOCK (element);
/* store the current stream time */
if (pipeline->stream_time != GST_CLOCK_TIME_NONE)
pipeline->stream_time = now - element->base_time;
GST_DEBUG_OBJECT (element,
"stream_time=%" GST_TIME_FORMAT ", now=%" GST_TIME_FORMAT
", base time %" GST_TIME_FORMAT,
GST_TIME_ARGS (pipeline->stream_time), GST_TIME_ARGS (now),
GST_TIME_ARGS (element->base_time));
}
GST_OBJECT_UNLOCK (element);
break;
case GST_STATE_CHANGE_PAUSED_TO_READY:
break;
case GST_STATE_CHANGE_READY_TO_NULL:
GST_OBJECT_LOCK (element);
if (element->bus) {
gst_bus_set_flushing (element->bus, TRUE);
}
GST_OBJECT_UNLOCK (element);
break;
}
return result;
invalid_clock:
{
GST_ELEMENT_ERROR (pipeline, CORE, CLOCK,
(_("Selected clock cannot be used in pipeline.")),
("Pipeline cannot operate with selected clock"));
GST_DEBUG_OBJECT (pipeline,
"Pipeline cannot operate with selected clock %p", clock);
return GST_STATE_CHANGE_FAILURE;
}
}
/**
* gst_pipeline_get_bus:
* @pipeline: the pipeline
*
* Gets the #GstBus of this pipeline.
*
* Returns: a GstBus
*
* MT safe.
*/
GstBus *
gst_pipeline_get_bus (GstPipeline * pipeline)
{
return gst_element_get_bus (GST_ELEMENT (pipeline));
}
/**
* gst_pipeline_set_new_stream_time:
* @pipeline: the pipeline
* @time: the new stream time to set
*
* Set the new stream time of the pipeline. The stream time is used to
* set the base time on the elements (see @gst_element_set_base_time())
* in the PAUSED->PLAYING state transition.
*
* Setting @time to #GST_CLOCK_TIME_NONE will disable the pipeline's management
* of element base time. The application will then be responsible for
* performing base time distribution. This is sometimes useful if you want to
* synchronize capture from multiple pipelines, and you can also ensure that the
* pipelines have the same clock.
*
* MT safe.
*/
void
gst_pipeline_set_new_stream_time (GstPipeline * pipeline, GstClockTime time)
{
g_return_if_fail (GST_IS_PIPELINE (pipeline));
GST_OBJECT_LOCK (pipeline);
pipeline->stream_time = time;
GST_OBJECT_UNLOCK (pipeline);
GST_DEBUG_OBJECT (pipeline, "set new stream_time to %" GST_TIME_FORMAT,
GST_TIME_ARGS (time));
if (time == GST_CLOCK_TIME_NONE)
GST_DEBUG_OBJECT (pipeline, "told not to adjust base time");
}
/**
* gst_pipeline_get_last_stream_time:
* @pipeline: the pipeline
*
* Gets the last stream time of the pipeline. If the pipeline is PLAYING,
* the returned time is the stream time used to configure the elements
* in the PAUSED->PLAYING state. If the pipeline is PAUSED, the returned
* time is the stream time when the pipeline was paused.
*
* Returns: a GstClockTime
*
* MT safe.
*/
GstClockTime
gst_pipeline_get_last_stream_time (GstPipeline * pipeline)
{
GstClockTime result;
g_return_val_if_fail (GST_IS_PIPELINE (pipeline), GST_CLOCK_TIME_NONE);
GST_OBJECT_LOCK (pipeline);
result = pipeline->stream_time;
GST_OBJECT_UNLOCK (pipeline);
return result;
}
static GstClock *
gst_pipeline_provide_clock_func (GstElement * element)
{
GstClock *clock = NULL;
GstPipeline *pipeline = GST_PIPELINE (element);
/* if we have a fixed clock, use that one */
GST_OBJECT_LOCK (pipeline);
if (GST_OBJECT_FLAG_IS_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK)) {
clock = pipeline->fixed_clock;
gst_object_ref (clock);
GST_OBJECT_UNLOCK (pipeline);
GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)",
clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
} else {
GST_OBJECT_UNLOCK (pipeline);
clock =
GST_ELEMENT_CLASS (parent_class)->
provide_clock (GST_ELEMENT (pipeline));
/* no clock, use a system clock */
if (!clock) {
clock = gst_system_clock_obtain ();
GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained system clock: %p (%s)",
clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
} else {
GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline obtained clock: %p (%s)",
clock, clock ? GST_STR_NULL (GST_OBJECT_NAME (clock)) : "-");
}
}
return clock;
}
/**
* gst_pipeline_get_clock:
* @pipeline: the pipeline
*
* Gets the current clock used by the pipeline.
*
* Returns: a GstClock
*/
GstClock *
gst_pipeline_get_clock (GstPipeline * pipeline)
{
g_return_val_if_fail (GST_IS_PIPELINE (pipeline), NULL);
return gst_pipeline_provide_clock_func (GST_ELEMENT (pipeline));
}
/**
* gst_pipeline_use_clock:
* @pipeline: the pipeline
* @clock: the clock to use
*
* Force the pipeline to use the given clock. The pipeline will
* always use the given clock even if new clock providers are added
* to this pipeline.
*
* MT safe.
*/
void
gst_pipeline_use_clock (GstPipeline * pipeline, GstClock * clock)
{
g_return_if_fail (GST_IS_PIPELINE (pipeline));
GST_OBJECT_LOCK (pipeline);
GST_OBJECT_FLAG_SET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
gst_object_replace ((GstObject **) & pipeline->fixed_clock,
(GstObject *) clock);
GST_OBJECT_UNLOCK (pipeline);
GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using fixed clock %p (%s)", clock,
(clock ? GST_OBJECT_NAME (clock) : "nil"));
}
/**
* gst_pipeline_set_clock:
* @pipeline: the pipeline
* @clock: the clock to set
*
* Set the clock for the pipeline. The clock will be distributed
* to all the elements managed by the pipeline.
*
* Returns: TRUE if the clock could be set on the pipeline.
*
* MT safe.
*/
gboolean
gst_pipeline_set_clock (GstPipeline * pipeline, GstClock * clock)
{
g_return_val_if_fail (pipeline != NULL, FALSE);
g_return_val_if_fail (GST_IS_PIPELINE (pipeline), FALSE);
return GST_ELEMENT_CLASS (parent_class)->set_clock (GST_ELEMENT (pipeline),
clock);
}
/**
* gst_pipeline_auto_clock:
* @pipeline: the pipeline
*
* Let the pipeline select a clock automatically.
*
* MT safe.
*/
void
gst_pipeline_auto_clock (GstPipeline * pipeline)
{
g_return_if_fail (pipeline != NULL);
g_return_if_fail (GST_IS_PIPELINE (pipeline));
GST_OBJECT_LOCK (pipeline);
GST_OBJECT_FLAG_UNSET (pipeline, GST_PIPELINE_FLAG_FIXED_CLOCK);
gst_object_replace ((GstObject **) & pipeline->fixed_clock, NULL);
GST_OBJECT_UNLOCK (pipeline);
GST_CAT_DEBUG (GST_CAT_CLOCK, "pipeline using automatic clock");
}